GB2637167A

GB2637167A - Improvements in and relating to data centres

Info

Publication number: GB2637167A
Application number: GB2400449.1A
Authority: GB
Inventors: Favill Aaron
Original assignee: Pripco Ltd
Current assignee: Pripco Ltd
Priority date: 2024-01-12
Filing date: 2024-01-12
Publication date: 2025-07-16
Also published as: WO2025149754A1; GB202400449D0

Abstract

A multi-level data centre building 9001 has multiple floors within a first building envelope 903, with each floor (in plan view here fig 11 – figs 9, 10 show side views) accommodating rack storage areas for rows of server racks 105, preferably arranged in segregated hot and cold aisles and with ceiling hot-air ducting (153 fig 9) arranged to exhaust hot air towards one side (left) of the building. A cowling 902 is attached to the exterior envelope and contains on each floor a plurality of (air) cooling units 120. The hot exhaust air exits via outlets 203 from a number of floors via a common exhaust conduit 901, which extends vertically (see figs 9,10) and may expel air through a top of the data centre. This exhaust conduit 901 perferably has a minimum cross-sectional area of at least 2m2, and/or comprise at least one personnel access door 960 providing personnel access to the exhaust conduit.

Description

Improvements in and relating to data centres

Field of the Invention

The present invention concerns data centres and a method of cooling servers in a data centre. More particularly, but not exclusively, this invention concerns data centres and methods of constructing data centres.

Background of the Invention

A data centre is understood to be a large group of networked computer servers, typically provided in a dedicated space within a building. For example, a modern data centre may include high density, high capacity IT systems in a specialist, dedicated space having a carefully controlled environment. A state of the art data centre may include multiple data halls each containing hundreds or even thousands of computer servers, typically contained in racks arranged in rows. In general, each server is provided with electrical power and a network connection. During operation, components of servers typically generate heat, which should be dissipated to avoid overheating and damage to equipment. Organisations, and also individuals, treat data centres as mission-critical facilities, meaning that even short periods of down-time due to equipment malfunction is not tolerated. With the increase in demand for cloud' computing services, there is a need not only for additional data centre facilities, but also higher capacity facilities. Alongside increases in computing power of individual servers, the number of servers in each rack, and the number of racks in each data hall increases with each new generation of data centres.

Various measures have been used to compare and contrast modern data centres, including the number of servers, building area, and power consumption. According to Data Centre Magazine, a hyperscale data centre should exceed 5,000 servers and 10,000 square feet, and the three largest data centre facilities in the world have total areas exceeding 7 million square feet. Hyperscale data centres often include multiple data halls, each being a single continuous space for accommodating servers. An individual data hall may include IT servers having a total power consumption of 3 MW or more. Racks, or cabinets, housing servers are -2 -typically arranged in rows separated by personnel aisles. In order to make efficient use of space, racks have become larger, and aisles longer. For example, a common modern rack design is capable of holding 42 servers stacked one on top the other (a '42U' rack). The dimensions of server racks have become highly standardised, particularly in terms of width. Racks are typically 600mm wide, and a 42U rack may have a height of about 2300 mm, a depth of 1050mm, and once fully loaded with servers may weigh as much as 2.4 tonnes. A single row of racks in the data hall of a Hyperscale data centre may be made up of 22 or more racks, with the data hall accommodating 14 or more rows. Such a high dead load weight concentrated in a relatively small area can present challenges in building design. For example, a single row of racks occupying a floor space of under 16 m2 (i.e. a row of racks taking up 15 m by 1.05 m) may weigh as much as 62.5 tonnes.

Data centres are sophisticated installations usually requiring high levels of accuracy in construction. Such requirements can make deployment of new facilities costly and time consuming. Traditionally, data centre facilities have been built using conventional construction methods, where a bespoke building shell is constructed first, and then fitted out with the necessary services and equipment on-site. Typically, cooling equipment is treated in a similar manner to HVAC (heating, ventilation and air conditioning) equipment of other buildings, which is often located outside the fabric of the building (also known as a building envelope). Such positioning can provide various advantages, for example allowing equipment to be craned into place at a late stage of construction and/or when replacement equipment is provided. Furthermore, during the planning and approval process when consent is sought for a new building, an important measure considered by authorities is the floor-space or volume of a building, which is taken to be the space within the fabric, or envelope. Accordingly, locating HVAC equipment outside the envelope, on roof-top or side gantries or platforms can help to maximise the usable area within the building envelope.

Air flow management is considered especially important in modern data centres, where there is a continuing drive for lower PUE (power usage effectiveness) values. PUE is the ratio of total data centre power consumption to server power consumption, and so minimising energy use for equipment cooling is often a high -3 -priority. W02010139921 (Bripco BVBA) describes an especially energy efficient data centre layout, in which the data centre is subdivided into segregated hot and cold zones, including alternating hot and cold aisles separated by rows of server cabinets. Each cold aisle is supplied with cooling air from a cold air corridor, that also functions as a personnel access corridor, that leads from an air handling unit. A yet further challenge for larger scale, ambient air-cooled data centres, particularly hyperscale data centres, is avoiding inadvertent mixing between warm air exhausted from the building and fresh ambient air being drawn into the building for use as fresh cooling air.

There remains a need for a data centre design that combines efficient use of space with cost-effective operational costs and convenient commissioning and maintenance. The present invention seeks to mitigate various problems of the prior art. Alternatively or additionally, the present invention seeks to provide an improved data centre, and method of cooling IT equipment in a data centre.

Summary of the Invention

The present invention provides, according to a first aspect, a multi-level data centre comprising a plurality of data levels, for example at least three data levels. Optionally, each data level accommodates at least fifteen, optionally at least twenty, rack storage areas positioned on a floor. Each rack storage area preferably has a width and a length and is arranged to accommodate a row of at least ten, such as at least twenty, server racks. Each server rack is capable of accommodating at least 20 servers, such as at least 30 servers. Preferably, the rack storage areas separate alternating hot aisles and cold aisles. Each cold aisle and each hot aisle may have a width and a length. Optionally, each level comprises a plurality of cooling units for cooling servers, such as air handling units for supplying cooling air to the servers via the cold aisles. Preferably, each cooling unit comprises an adiabatic cooling unit. Optionally, each level comprises a cold air supply corridor for transporting cold air from air handling units to cold aisles, and preferably being suitable for providing personnel access to the cold aisles. Such a cold air supply corridor is in fluid communication with the cold aisles, for example through opening arranged along a first side of the corridor. Optionally, such a cold air supply corridor may be -4 -positioned between, such as sandwiched between the air handling units and the cold aisles. Optionally, such air handling units may supply cooling air into a first side of the corridor, and the cold aisles may receive cooling air from a second opposed side of the corridor. Additionally or alternatively, such air handling units and cold aisles may be distributed along the length of the cold corridor on opposed sides, for example wherein an end of each cold aisle communicates with the cold corridor. Optionally, a cold air supply corridor extends perpendicular to cold aisles. For example, the cold air supply corridor has a width and a length, the length extending perpendicular to the cold aisles. Optionally, each level comprises a warm air return path for transporting warm air from the hot aisles to air handling units. Optionally, a plurality of air handing units is positioned along a second side of the cold air supply corridor opposite the first side (and thus opposite the cold aisles). Optionally, such rack storage areas, cold aisles, hot aisles, cold air supply corridor, and warm air return path are positioned within the building envelope. Optionally, the plurality of cooling units (such as air handling units) is positioned outside the building envelope.

It has been found that such arrangements confer a number of advantages. For example, a cold air supply corridor allows for high volumes of cooling air to be distributed to cold aisles at low velocity, the corridor allowing air from the air handling units to mingle and provide all cold aisles with cooling air even in the event of limited performance or failure of one or more air handling units. Furthermore, positioning multiple air handling units along the cold air supply corridor (e.g. along a side of the corridor) has been found to allow an especially high density of racks on each level, for example by allowing longer aisles with larger server racks without compromising availability of cooling air. The present inventors have further recognised that positioning air handling units along a common air supply corridor helps to make efficient use of space inside the building, for example because equipment redundancy can be provided across the level, rather than for each cold aisle, while also keeping air handling equipment in close proximity to the cold aisles. Optionally, the cold corridor transports cooling air to at least five cold aisles, such as at least seven cold aisles, and receives cooling air from at least three air handling units. -5 -

Optionally, the data centre comprises an exhaust conduit for directing exhaust air, such as directing exhaust air away from the air intake vents (e.g. controllable air intake vents). Optionally, the exhaust conduit is outside the building envelope. Optionally, the exhaust conduit comprises a plurality of sides extending from a closed lower end to an open upper end, wherein at least one side comprises one or more openings for receiving warm air exhausted by controllable exhaust vents of the building. Optionally, one or more sides of the exhaust conduit is formed by a portion of the building envelope, such as by an exterior wall of the building. Preferably, the exhaust conduit extends upwards from the lowermost data level, for example to the uppermost data level and/or to the top or roof of the building, for example wherein the open upper end of the conduit is positioned at or close to the top or roof. Optionally, each exhaust conduit is configured to receive exhaust air from outlets (e.g. controllable exhaust vents) of a plurality of data levels, such as all data levels. It has been found that such an exhaust conduit can function as a chimney, allowing warm exhaust air to rise naturally to the top of the building away from air intakes. Optionally, the multi-level data centre comprises an exhaust conduit for receiving warm air from at least one outlet (e.g. controllable outlet vent) of each of at least two data levels. Optionally, the exhaust conduit has at least two sides comprising a first side formed by the building envelope and a second side formed by a cowling. It has been found that forming at least one side of the exhaust conduit from the building envelope provides a particularly efficient structure. Optionally, the exhaust conduit comprises a third side formed by the building envelope. Optionally, the first and third sides each comprise a controllable outlet vent at each level. Optionally, the exhaust conduit comprises a fourth side formed by the building envelope, the fourth side being opposed to the second side, and the first side being opposed to the third side. Optionally, each data level may comprise an air handling unit positioned adjacent each of opposed first and third sides of the exhaust conduit. It has been found that such an arrangement can be especially effective at helping to maintain exhaust and intake air separation, especially when a data level comprises numerous air handling units positioned along the length of a cold air supply corridor. Optionally, there may be no outlets (e.g. controllable exhaust vents) not associated with such an exhaust conduit. Optionally, the at least -6 -one exhaust conduit (e.g. each exhaust conduit) may have an internal cross-sectional area of at least 2m2, such as at least 4m2, for example at least 9m2. Additionally or alternatively, the at least one exhaust conduit (e.g. each exhaust conduit) optionally has a minimum internal dimension of at least 1m, such as at least 2m, for example at least 3m. For example, the at least one exhaust conduit (e.g. each exhaust conduit) has a length and an internal width, the length being the longest internal dimension, and the exhaust conduit optionally has an internal width of at least 1m, such as at least 2m, for example at least 3m. Optionally, the at least one exhaust conduit (e.g. each exhaust conduit) has a length, an internal width and an internal depth, wherein the length is at least 3m, such as at least 6m, and each of the internal width and the internal depth is at least 1m, such as at least 2m. It will be understood that such an exhaust conduit optionally has an internal cross-section of at least 1m x 2m, thus at least 2m2. Optionally, the at least on exhaust conduit has an air transport section, the air transport section extending from an exhaust conduit inlet to an exhaust conduit outlet, for example wherein the exhaust conduit inlet communicates with a data level warm air outlet and/or the exhaust conduit outlet communicates with ambient environment outside the data centre. Optionally, the transport section has a minimum internal diameter of at least 2m2, such as at least 4m2. Optionally, the air transport section has a minimum internal dimension of at least 1m. Optionally, the air transport section has a length (from said exhaust conduit inlet to said exhaust conduit outlet) of at least 3m, such as at least 6m. Optionally, the at least one exhaust conduit is sized and configured to allow personnel access, for example to allow a person to enter and move around inside the exhaust conduit. Optionally, the at least one exhaust conduit spans multiple data levels and/or comprises an upper region divided from a lower region by open mesh flooring, such as steel open mesh flooring. It will be understood that open mesh flooring may provide a walkway or decking that offers adequate support for persons to walk on the flooring while also allowing air to flow through the flooring. Open mesh flooring may also be referred to as grating and is often used in gantry structures exterior to building envelopes.

Optionally, the open mesh flooring allows convenient personnel access to such an upper region of the exhaust conduit. Optionally, when the at least one exhaust conduit spans multiple data levels, the exhaust conduit is divided into a -7 -corresponding number of regions by one or more sections of open mesh flooring. Optionally, each such region is accessible from outside the exhaust conduit by one or more exhaust conduit personnel access doors, for example including a lower access door and an upper access door. Optionally, the at least one exhaust conduit provides personnel access to at least one side of an air handling unit via at least one exhaust conduit personnel access door, optionally wherein the at least one exhaust conduit provides personnel access to at least one component of an air handling unit via at least one exhaust conduit personnel access door. Optionally, the exhaust conduit provides access to a plurality of air handler units arranged on multiple data levels, for example via at least one exhaust conduit personnel access door.

Optionally, the data centre of the first aspect of the invention is a data centre according to claim 1, and the claims dependent thereon.

As used here, the 'building envelope' is the physical separator between the conditioned and unconditioned environment of a building, including for example the resistance to air, water, heat, light, and/or noise transfer between the interior and exterior of the building. Also known as the 'building enclosure', the building envelope may comprise the elements of the outer shell that maintain a dry, heated, or cooled indoor environment and facilitate its climate control. It will be understood that equipment mounted on gantry structures on the sides and/or top of a building are not located within a building envelope. For example, air handling equipment located on such gantry structures and fluidly connected to the internal space of the building via duct-work and/or piping are considered as being located outside the building envelope. Additionally or alternatively, the building envelope may be referred to as the 'interior' of the building, while areas outside the building envelope may be referred to as the 'exterior', for example wherein personnel are able to move between all personnel areas located in the interior without having to exit the building envelope (i.e. without having to pass to the exterior and back into the interior again). A data centre in which air handling units are also located within the building envelope is disclosed in GB2217691.1 (Pripco Limited) filed on 25 November 2022, and PCT/GB2023/053070 (Pripco Limited) filed on 24 November 2023 (claiming priority from GB2217691.1); it will be understood that the claims of the present application exclude a data centre building as claimed in either of those -8 -earlier applications. Thus, the data centre optionally is not a data centre as disclosed in GB2217691.1 or PCT/GB2023/053070.

It will be understood that a rack storage area is a space sized and configured to accommodate the (e.g. row of) server racks, for example a row of at least 20 server racks. Optionally, the server racks that may be accommodated are 42U or larger server racks, meaning racking capable of holding 42 or more servers. In an air-cooled data centre, IT equipment (which becomes hot during use) is cooled by contact with cooling air. Such cooling air may be supplied by one or more air handling units. As used herein: a 'cold aisle' of an operational data centre is a space adjacent a row of racks (for example between opposed rows of racks) from which rack-mounted IT equipment is able to draw cooling air; a 'hot aisle' is a space adjacent a row of racks (for example between opposed rows of racks) into which rack-mounted IT equipment is able to expel warm air. Typically, operational efficiency is improved by segregating hot aisles and cold aisles, thereby avoiding cooling air in a cold aisle mixing with warm air from a hot aisle before being used to cool IT equipment. Optionally, each cold aisle has a width of from 1m to 2m, such as 1.4m to 1.6m. Optionally, each hot aisle has a width of from 1m to 2m, such as 1m to 1.4m. Optionally, each rack storage area has a width of from 1m to 1.5m, such as about 1.2m. It will be understood that warm air may, for example, be air having a temperature higher than supply air (e.g. at least 5°C higher, such as at least 10°C higher), supply air being air supplied to servers (e.g. via cold aisles) for cooling, and/or air that has a temperature higher than ambient air outside the data centre (e.g. at least 5°C higher, such as at least 10°C higher).

Optionally, each data level comprises at least three, such as at least four air handing units in fluid communication with the, or each, cold air supply corridor.

Optionally, each data level comprises no more than eight, such as no more than six, air handling units in fluid communication with the, or each, cold air supply corridor. It will be understood that each data level may, for example, comprise one or more additional cold air supply corridors and associated cold and hot aisles, air handling units and warm return space. Optionally, each such cold air supply corridor, associated cold and hot aisles, air handling units and warm return space forms a data hall. Optionally, each data level comprises a plurality of data halls, such as at least -9 -three data halls, for example at least four data halls. Optionally, there are at least four, optionally at least five, data levels.

Optionally, the data centre comprises a plurality of server racks located in the rack storage areas. Optionally, each server rack accommodates at least 20, such as at least 30, for example at least 40, servers. Optionally, the racks together with air entrainment panels segregate the hot and cold aisles. Optionally, the data centre is a hyperscale data centre, for example accommodating at least 5,000 servers (rack-mountable items of IT equipment), and/or having an IT floor-space of at least 10,000 square feet. It will be understood that IT floor-space is the sum total of space occupied by rack storage areas, cold aisles and hot aisles, in the data centre.

Optionally, each data level comprises at least 15 rack storage areas each able to accommodate at least 20 racks, for example wherein each data level is configured to accommodate at least 300 racks, for example 300 racks capable of housing at least 40 severs. In such an arrangement, each data level is optionally capable of accommodating at least 12,000 servers. Optionally, each data level has a single IT area comprising rack storage areas, cold aisles and hot aisles. It will be appreciated that each data level may for example accommodate two or more separate IT areas. Optionally, each IT area is configured to accommodate at least 12,000 servers. Optionally, each IT area occupies a floor space of at least 1,000 square metres. A hyperscale data centre may be one that is configured, when fully operational, to be capable of operating at total power levels of at least 40MW.

Optionally, the cold air supply corridor has a length extending perpendicular to and being in fluid communication with the cold aisles of the data level to receive from the cold air supply corridor cooling air supplied to the cold air supply corridor by a plurality of air handling units. A suitable cold corridor / cold aisle arrangement is described in W02010139921 (Bripco BVBA), the contents of which are incorporated by reference. Specifically, that document describes a data centre layout which utilises personnel space for transport of large volumes of cooling air at low velocity, improving operating efficiency and making better use of space. Preferably, the air supply corridor is a personnel corridor, for example having a height of at least 3 m, such as at least 3.5 m, and a width of at least 2 m, such as at least 2.5 m, and optionally a length of at least 30 m, such as at least 40 m. Optionally, the air handling -10 -units are positioned alongside and distributed along the length of the cold air supply corridor. Optionally, during operation of the data centre, cooling air from the air handing units enters the corridor through openings in the side of the corridor along its length.

Optionally, the warm air zone comprises a warm air plenum, e.g. the warm air return space or path is a warm air plenum. Optionally, the warm air plenum extends above the cold aisles, the cold air supply corridor, and/or and the air handling units. It has been found that such an arrangement provides a particularly space efficient layout, for example by avoiding the need for extra floor space in to accommodate the warm air return space. Optionally, the warm air plenum is segregated from the cold aisles and the cold air supply corridor by a plurality of air entrainment panels suspended from a data level ceiling structure. It will be understood that the ceiling structure may be part of the load-bearing structure of the building, for example forming the floor of a level above. Optionally, the plurality of data levels comprises an uppermost data level, the ceiling structure of the uppermost data level forming at least a portion of a roof of the multi-level data centre. Additionally or alternatively the plurality of data levels comprises a lowermost data level, the floor of the lowermost data level being the ground floor of the multi-level data centre. Optionally, each data level includes one or more cold aisle service cassettes suspended from the ceiling structure. Service cassette systems are also disclosed in W02017129448 (Bripco BVBA), the contents of which are incorporated by reference. Specifically, that document discloses cassettes suspendable from a building structure and equipped with air entrainment panels and data centre services. Preferably, each cold aisle service cassette comprises components of a plurality of data centre services, such as at least three services. For example, components may include a conduit for fire suppressant fluid, a cable tray, electrical power components (such as cabling and/or a bus-bar), networking cabling, lighting equipment and/or sensor equipment (such as motion, temperature and/or humidity sensor equipment). Optionally, each cold aisle service cassette comprises aisle air entrainment panels configured to cooperate with racks of IT equipment to segregate the hot and cold aisles. Optionally, each cold aisle service cassette comprises ceiling air entrainment panels configured to segregate cold aisles from a warm air plenum disposed between the ceiling air entrainment panels and said ceiling structure, said warm air plenum being in fluid communication with one or more hot aisles adjacent said cold aisle. For example, each data centre level may comprise a warm air plenum for receiving hot air from hot aisles and transporting hot air to air handling units and/or exhaust vents on the building envelope.

Optionally, said warm air plenum is positioned above the cold aisles, for example being segregated from said cold aisles by ceiling air entrainment panels.

Optionally, each air handling unit has a first end for receiving air to be treated and a second end for discharging treated air. Preferably, the first end is opposed to the second end and the adiabatic cooling unit is positioned between the first end and the second end. Optionally, the second end is positioned at the second side of the cold air supply corridor. Optionally, the first end is positioned at or adjacent the building envelope. Optionally, the air handling unit has an airflow path that extends in a straight line from the first end to the second end, for example wherein the airflow path extends in a direction parallel to the length of the cold aisles and perpendicular to the length of the cold air supply corridor. It has been found that with such an arrangement, cooling air provided by the air handling units tends to efficiently flow across the cooling air supply corridor into ends of the cold aisles.

Optionally, the data centre comprises on each data level a plurality of controllable intake vents for admitting ambient air into the data centre, optionally wherein each intake vent is in fluid communication with an air handling unit. Optionally, each air handling unit is in fluid communication with at least one intake vent. Optionally, the data centre comprises on each data level a plurality of controllable outlet vents for exhausting warm air (e.g. into an exhaust conduit), optionally wherein each outlet vent is in fluid communication with the warm air return path. Optionally, each data level comprises a plurality of controllable recirculation vents for controlling admission of warm air from the warm air return path to the air handling units. Optionally, each controllable inlet vent is positioned at or adjacent the second end of an air handling unit. In such an arrangement, ambient air may for example directly enter the air handing unit. Optionally, each controllable outlet vent is positioned above an air handling unit. For example, it may be that each controllable outlet vent is positioned immediately above an air handling unit.

-12 -Optionally, each data level comprises at least three air handling units for providing cooling air to cold aisles. Optionally, the air handling units are direct air handling units. It will be understood that a direct air handling unit provides cooling air that comprises or consists of a portion of ambient air from outside the data centre, optionally where said ambient air is treated to adjust its temperature and/or humidity. Direct air handling units, and suitable control methodologies are disclosed in W02011/148175A1 (Bripco BVBA), the contents of which are incorporated herein by reference. Alternatively, the air handling units are indirect air handling units. Suitable indirect air handling units are disclosed in W02016/207323A1 (Bripco BVBA), the contents of which are incorporated herein by reference. It will be understood that an indirect air handling unit provides air that consists substantially of (for example consists entirely of) air from inside the data centre, optionally having been treated to adjust its temperature and/or humidity. Optionally, an indirect air handling unit comprises a heat exchanger for transferring heat from air inside the building to air from outside the building, for example wherein internal air travels through the air handling unit along an internal airflow path segregated from an external airflow path along which air from outside the building travels. Preferably, the air handling units comprise adiabatic cooling units, and optionally are free from mechanical cooling units (such as direct expansion cooling units). It will be understood that a direct expansion mechanical cooling unit provides cooling by contacting air with coils containing a refrigerant that had been compressed then allowed to expand. Suitable adiabatic cooling units include so-called wetted matrix coolers (in which air to be cooled is passed through an array of a wetted material) and spray coolers. Optionally, e.g. when the air handling units are direct air handling units, the data level warm air outlets communicate with a data level warm air zone, e.g. the warm air zone being arranged to transport warm air from servers to warm air outlets and optionally air handling units. Optionally, e.g. when the air handling units are indirect air handling units, the data level warm air outlets are in fluid communication with air handling unit external airflow paths.

Optionally, each intake vent is arranged to admit ambient air substantially horizontally, and each exhaust conduit is arranged to transport air (e.g. warm air) substantially vertically and optionally to expel air (e.g. warm air) substantially -13 -vertically. Air is admitted substantially horizontally if average airflow direction of air admitted through the inlet is substantially horizontal, substantially horizontal being within 30°, e.g. within 15°, of horizontal. Air is transported substantially vertically when average airflow travels from a first lower position to a second upper position, the second upper position being above the first lower position relative to a floor of the data centre. It will be understood that air transported vertically may also be transported horizontally, unless stated to be transported only vertically. Optionally, each exhaust conduit is arranged to transport air only substantially vertically. It will be understood that air is transported only substantially vertically when air transported by the conduit travels from a first lower position to a second upper position, wherein the second upper position is above the first lower position relative to a floor of the data centre, and wherein the first lower and second upper positions each line on an axis that is substantially vertical, an axis being substantially vertical if oriented the second upper position is within 30°, e.g. within 15°, of vertical. Air is expelled from the data centre substantially vertically when average airflow direction of air expelled from the data centre is substantially vertical, substantially vertical being within 30°, e.g. within 15°, of vertical. It will be understood that the terms vertical and horizontal have their normal meanings, for example according to which a vertical axis is that along which a plumb-bob hangs. Additionally or alternatively, the intake vents and each exhaust conduit are optionally arranged so that: (i) ambient air drawn into the data centre is drawn in from an ambient environment beside the data centre, and (ii) air (e.g. warm air) expelled from the data centre is expelled to an ambient environment above the data centre. The present inventors have found that such an arrangement can help to avoid unwanted re-entry of exhaust air (e.g. warm exhaust air) into the building, which may for example occur when inlet and outlet vents are placed on the same side of a building and/or in close proximity.

Optionally, serviceable components of each air handling unit are accessible via one or more of the exhaust conduits Optionally, adiabatic coolers of air handling units (and other components if present, such as filter banks and/or fan banks) are accessible for servicing from an exhaust conduit. It has been found that such an arrangement provides an especially convenient and pleasant access route for -14 -personnel. It will be understood that a serviceable component is a component to which access is expected to be required during the planned working life of the air handling unit, for example to repair, clean and/or replace a component expected to deteriorate during normal use. Optionally, each air handling unit comprises a plurality of sections. For example, a direct air handing unit may comprise a filter bank at the first end, or between the first end and the adiabatic cooling unit. From time to time, filters in the filter bank may require repair, cleaning or replacement. Additionally or alternatively, each air handling unit optionally comprises a plurality of fans for controlling transport of cooling air from the air handling unit to the servers via the cold air supply corridor and the cold aisles. For example, each air handling unit may comprise a fan bank for air circulation. It will be appreciated that such fans may require periodic inspection, repair and/or replacement. Optionally, each air handling unit is subdivided into a plurality of sections, for example where each section is accessible through a side-door that provides access from the exhaust conduit.

Optionally, each air handling unit is located on a data level between the floor level and the ceiling level of the data level, for example outside an exterior wall of the data centre. It will be understood that an exterior wall forms part of the weather-tight shell of a building. Optionally, said floor level of a data level is a substantially continuous level that is coplanar with the floor of the data level on which components of the data level are supported (including IT racks and air handling units). Similarly, said ceiling level is optionally a substantially continuous level which is coplanar with the ceiling of the data level from which overhead services are suspended.

Optionally, the multi-level data centre comprises a service riser area, for example accommodating data centre services extending between data levels. Optionally, the service riser area extends across multiple, e.g. all, data levels, for example providing a services route from lower to higher levels. Preferably, such a riser area is contained within the building envelope.

Optionally, each air handling unit comprises one or more, optionally multiple, air blenders positioned between an adiabatic cooling unit and the cold air supply corridor. It will be understood that an air blender is a device that promotes air -15 -mixing. It has been found that such air mixing can help improve cooling air homogeneity. Optionally, each air blender comprises a plurality of fins oriented to disrupt air flow thereby mixing air flowing through the air handling unit. It has been found that mounting air blenders on the air handling units helps to maximise the free personnel space in the cold air supply corridor.

According to a second aspect, there is provided a multi-level data centre comprising a plurality of vertically separated levels. Preferably, each level is positioned between a floor and a ceiling, and is bounded by at least one exterior wall of the building. It will be understood that an exterior wall of a building is a part of the shell (or envelope) of a building that provides a physical separation between the interior of a building and the exterior, for example being a weather-tight barrier. Optionally, each data level comprises at least fifteen rack storage areas positioned on the floor, each rack storage area being arranged to accommodate (e.g. a row of) at least ten server racks each capable of accommodating at least twenty servers, the rack storage areas optionally separating interleaved hot aisles and cold aisles.

Optionally, each level comprises at least three cooling units for cooling servers (e.g. air handling units for supplying cooling air to the servers via the cold aisles), optionally wherein each cooling unit comprises an adiabatic cooling unit. Optionally, each level comprises a cold air supply corridor for transporting cold air from the air handling units to the cold aisles above the floor and for providing personnel access to the cold aisles. Optionally, each level comprises a warm air return path for transporting warm air from the hot aisles to the air handling units. Optionally, the cooling units (e.g. air handing units) are located outside the at least one exterior wall of the building. Optionally, the cold air supply corridor is in fluid communication with the cold aisles through openings arranged along a first side of the cold air supply corridor. Optionally, the cold air supply corridor is in fluid communication with the air handling units through openings arranged along a second opposed side of the cold air supply corridor. Optionally, the data centre comprises an exhaust conduit for receiving warm air from at least one warm air outlet of each of the plurality of levels.

Optionally, the data centre of the second aspect of the invention is a data centre according to claim 2 and the claims dependent thereon.

-16 -Optionally, each air handling unit has a first end for receiving air to be treated and a second end for discharging treated air, the first end being opposed to the second end and the adiabatic cooling unit being positioned between the first end and the second end. Preferably, the second end is positioned at the second side of the cold air supply corridor. Preferably, the second end is positioned at or adjacent said at least one exterior wall of the building. Optionally, each data level comprises one or more of: (1) a plurality of controllable intake vents for admitting ambient air into the data centre, optionally wherein each controllable intake vent is in fluid communication with an air handling unit, optionally wherein each air handling unit is in fluid communication with at least one intake vent; (2) a plurality of controllable outlet vents for exhausting air out of the data centre via an exhaust conduit, optionally wherein each controllable outlet vent is in fluid communication with the warm air return path. Optionally, each data level comprises a plurality of controllable recirculation vents for controlling admission of warm air from the warm air return path to the air handling units.

Optionally, the data centre comprises an exhaust conduit for receiving warm air from at least one controllable outlet vent of each of the plurality of levels, optionally wherein the exhaust conduit has at least two sides comprising a first side formed by one exterior wall of the building and a second side formed by a cowling. It will be appreciated that walls may be understood as those vertical parts of the building shell that meet at a corner.

It will be appreciated that the data centre of the second aspect of the invention may incorporate any feature described with referenced to the data centre of the first aspect of the invention, and vice versa. In particular, it will be understood that the data centre of the second aspect of the invention may incorporate any feature of an exhaust conduit described in relation to the first aspect of the invention.

According to a third aspect, the present invention provides a multi-level data centre, for example comprising at least three data levels. Optionally, each data level comprises at least fifteen rack storage areas positioned on a floor, each rack storage area being arranged to accommodate (e.g. a row of) at least ten server racks each capable of accommodating at least twenty servers. Optionally, each data level comprises a plurality of cooling units for cooling the servers, e.g. air handling units -17 -for providing cooling air to servers, each cooling unit optionally comprising an adiabatic cooling unit. Optionally the data centre comprises on each level a plurality of intake vents for admitting ambient air into the data centre, preferably wherein each intake vent is in fluid communication with an air handling unit. Optionally each intake vent is arranged to admit ambient air through a side of the data centre.

Optionally, the data centre comprises at least one exhaust conduit for expelling air (e.g. warm air) out of the data centre, preferably wherein each exhaust conduit is in fluid communication with at least one outlet of at least one data level. Optionally each data level warm air outlet communicates with at least one exhaust conduit.

Preferably, a data level warm air outlet is an outlet arranged and configured to expel warm air generated directly or indirectly by cooling of servers, for example warm exhaust air from a cooling unit and/or warm exhaust air from servers. Additionally or alternatively, a data level warm air outlet is preferably a component (for example a controllable component) of a data centre server cooling system. Optionally, each exhaust conduit is arranged to expel air (e.g. warm air) through a top of the data centre.

Optionally, the data centre of the third aspect of the invention is a data centre according to claim 3 and the claims dependent thereon.

It will be appreciated that the data centre of the third aspect of the invention may incorporate any feature described with referenced to the data centre of the first or second aspect of the invention, and vice versa. In particular, it will be understood that the data centre of the third aspect of the invention may incorporate any feature of an exhaust conduit described in relation to the first aspect of the invention.

According to a fourth aspect, the present invention provides a multi-level data centre, for example comprising at least three data levels. Optionally, each data level comprises at least fifteen rack storage areas positioned on a floor, each rack storage area being arranged to accommodate (e.g. a row of) at least ten server racks each capable of accommodating at least twenty servers. Optionally, each data level comprises a plurality of cooling units for cooling the servers (e.g. air handling units for providing cooling air to the servers), each cooling unit optionally comprising an adiabatic cooling unit. Optionally, the data centre comprises on each level a plurality of intake vents for admitting ambient air into the data centre, preferably wherein -18 -each intake vent is in fluid communication with a cooling unit. Optionally, the data centre comprises at least one exhaust conduit for expelling air (e.g. warm air) out of the data centre, preferably wherein the exhaust conduit is in fluid communication with at least one warm air outlet of each of at least two data levels. Optionally, the exhaust conduit comprises at least one personnel access door providing personnel access to the exhaust conduit.

Optionally, the data centre of the fourth aspect of the invention is a data centre according to claim 4 and the claims dependent thereon.

It will be appreciated that the data centre of the fourth aspect of the invention may incorporate any feature described with referenced to the data centre of the first, second or third aspect of the invention, and vice versa. In particular, it will be understood that the data centre of the fourth aspect of the invention may incorporate any feature of an exhaust conduit described in relation to the first aspect of the invention.

According to a fifth aspect, there is also provided a method of cooling servers in a multi-level data centre of any one of the first, second, third or fourths aspects of the invention. Optionally, the method comprises operating the cooling units to cool the servers, for example operating air handing units to provide cooling air for cooling the servers. Optionally, the method comprises transporting cooling air from the air handling units to the servers via the cold air supply corridor and the cold aisles.

Optionally, the method comprises transporting warm air from the servers to the air handling units via the warm area. Optionally, the method comprises transporting air along an airflow path leading from the air handling units to the servers via the cold air supply corridor and the cold aisles and from the servers to the air handling units via the warm area, wherein the airflow path is located within the building.

Optionally, the method comprises expelling warm air into the exhaust conduit, wherein warm air from multiple levels of the data centre is expelled into at least one common exhaust conduit, optionally wherein the exhaust conduit conveys exhaust air away from air intakes on the building, for example towards and out of an open second end positioned at or near the roof or top of the building.

Optionally, the method of the fifth aspect of the invention is a method according to claim 21 or 22.

-19 -Optionally, the method of the fifth aspect of the invention is a method of cooling servers in a data centre according to any of the first, second, third or fourth aspects of the invention. It will be appreciated that the method of the fifth aspect of the invention may incorporate any feature described with reference to the data centre of the first, second, third or fourth aspects of the invention, and vice versa. In particular, it will be understood that the method of the fourth aspect of the invention may incorporate any feature of an exhaust conduit described in relation to the first aspect of the invention.

According to a sixth aspect of the invention, there is provided a method of making a multi-level data centre, e.g. comprising at least three data levels.

Optionally, the method comprises creating each data level by defining on a floor of the building at least fifteen rack storage areas (e.g. at least twenty rack storage areas), each rack storage area being arranged to accommodate (e.g. a row of) at least ten server racks each capable of accommodating at least twenty servers, the rack storage areas optionally separating alternating hot aisles and cold aisles.

Optionally, the method comprises defining on said floor a cold air supply corridor for transporting cold air from air handling units to the cold aisles and for providing personnel access to the cold aisles, the cold air supply corridor being in fluid communication with the cold aisles through openings preferably arranged along a first side of the cold air supply corridor. Optionally, the method comprises installing on each floor a plurality of cooling units for cooling servers, for example air handling units for supplying cooling air to the servers via the cold aisles, optionally wherein each cooling unit comprises an adiabatic cooling unit. Optionally, the method comprises forming within each data level a warm air return path for transporting warm air from the hot aisles to the air handling units.

Optionally the rack storage areas, cold aisles, hot aisles, cold air supply corridor, and warm air return path are positioned within the building envelope. Optionally, the cooling units (e.g. air handling units) are positioned outside the building envelope.

Additionally or alternatively, the method optionally comprises forming each level between a floor and bounding each level by at least one exterior wall of a building. Optionally, the cooling units (e.g. air handling units) are located outside the exterior -20 -wall of the building. Optionally the rack storage areas, cold aisles, hot aisles, cold air supply corridor, and warm air return path are located inside exterior wall of the building.

Additionally or alternatively, each exhaust conduit is optionally in fluid communication with at least one warm air outlet of at least one data level.

Preferably, each data level warm air outlet communicates with at least one exhaust conduit. Preferably, each exhaust conduit is arranged to expel air (e.g. warm air) through a top of the data centre.

Additionally or alternatively, the exhaust conduit is optionally in fluid communication with at least one warm air outlet of each of at least two data levels.

Preferably, the exhaust conduit comprises at least one access door providing personnel access to the exhaust conduit.

Optionally, the method comprises forming at each data level at least one of: (1) a plurality of intake openings for admitting ambient air into the data centre, each preferably comprising a controllable intake vent, optionally wherein each intake opening is in fluid communication with an air handling unit, optionally wherein each air handling unit is in fluid communication with at least one intake opening; (2) a plurality of outlet openings for expelling air into an exhaust conduit, each preferably comprising a controllable outlet vent, optionally wherein each outlet opening is in fluid communication with the warm air return path. Optionally, the method comprises forming an exhaust conduit for receiving warm air from at least one outlet opening of each of the plurality of levels. Optionally the exhaust conduit has at least two sides comprising a first side formed by one exterior wall of the data centre and a second side formed by a cowling.

Optionally, the method of the sixth aspect of the invention is a method according to any of claims 23 to 25.

Optionally, the data centre formed according to the method of the sixth aspect of the invention is a data centre according to any of the first, second, third or fourth aspects of the invention. It will be appreciated that the method of the sixth aspect of the invention may incorporate any feature described with reference to the data centre of the first, second, third or fourth aspects of the invention, and vice versa.

-21 -Optionally, the data centre formed according to the method of the fifth aspect of the invention is a data centre according to the third aspect of the invention. It will be appreciated that the method of the fifth aspect of the invention may incorporate any feature described with reference to the data centre of the third aspect of the invention and vice versa. In particular, it will be understood that the method of the sixth aspect of the invention may incorporate any feature of an exhaust conduit described in relation to the first aspect of the invention.

It will of course be appreciated that features described in relation to one aspect of the present invention may be incorporated into other aspects of the present invention. For example, the method of the invention may incorporate any of the features described with reference to the apparatus of the invention and vice versa.

Description of the Drawings

Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings of which: Figure 1 shows a side cross-sectional view of a multi-level data centre according to an embodiment of the invention; Figure 2 shows an enlarged portion of the drawing of Figure 1; Figure 3 shows a further enlarged portion of the drawing of Figure 1; Figure 4 shows an end cross-sectional view through a portion of the data centre of Figure 1; Figure 5 shows an enlarged view of a portion of Figure 4; Figure 6 shows a side cross-sectional view through a portion of the data centre of Figure 1; Figure 7 shows an end elevation of the data centre of Figure 1; Figure 8a shows a plan view of data level of the data centre of Figure 1; Figure 8b shows the plan view of Figure 8a, annotated to indicate the positions of the views of Figures 1, 4, 6 and 7; Figure 9 shows a side cross-sectional view through a portion of a data centre according to another embodiment of the invention; Figure 10 shows an end cross-sectional view through the data centre of Figure 9; Figure 11a shows a plan view of data level of the data centre of Figure 9; -22 -Figure llb shows the plan view of Figure 11a, annotated to indicate the positions of the views of Figures 9 and 10; Figure 12 illustrates steps of a method of cooling servers in the multi-level data centres of Figures 1-11b; Figure 13 illustrates steps of a method of constructing the multi-level data centres of Figures 1-11b.

Detailed Description

Figure 1 shows a side cross-sectional view of a multi-level data centre 101 according to the invention. The building 101 comprises a mechanical and electrical services level 102a on the ground floor, and three data levels 102b, 102c, 102d on the floors above. The mechanical and electrical services level 102a houses ancillary equipment, including 'uninterrupted power supply' (UPS) equipment, and power and data distribution equipment, not shown in Figure 1. Each data level 102b-d comprises twenty rack storage areas arranged between alternating hot and cold aisles, with each rack storage area accommodating a row of 31 server racks 105. The server racks each hold up to 42 servers. The view shown in Figure 1 cuts along a cold aisle, and thus illustrates the fronts of server racks 105.

Each data level 102b-d comprises a plurality of air handling units for providing cooling air to the cold aisles. Figure 1 shows air handling units 120b-d of data levels 102b-d, respectively. Illustrated in Figure 1 are the side covers and access doors of the air handler units 120b-d.

When the data centre 101 is operational, cooling air is supplied by air handler units 120b/c/d into cold corridors 150b/c/d, respectively. The cold corridors 150b/c/d run perpendicular to cold aisles, receiving cooling air from the multiple air handlers on each data level and transporting said cooling air to the multiple cold aisles. From the cold aisles, cooling air passes into server racks 105, thereby cooling the servers and becoming warm air and exiting into the hot aisles. Warm air passes upwards from the hot aisles to overhead warm air return plenums 153b/c/d on each level, and then into a warm air return space 154b/c/d above the air handler units 120b/c/d. From that space, warm air may be ejected from the building through warm air exhaust vents (not shown in Figure 1) and/or passed into mixing chambers -23 - 155b/c/d upstream of the air handler units 120b/c/d for mixing with ambient air from outside the building 101. Ambient air enters the mixing chambers 155b/c/d through air intake vents (not shown in Figure 1).

Figure 2 shows an enlarged portion of the drawing of Figure 1, annotated with the same reference numerals as used in Figure 1. As shown in Figure 2 with reference to air handler unit 120d, the air handler unit 120d is made up of multiple sections. The sections include a filter bank 121d, a fan bank 122d, an adiabatic cooler (such as a wetted matrix cooling system) 123d, and an air blender 124d. An access door 125d provides access to the mixing chamber 155d, and further access doors 126d, 127d and 128d provide access to the section of the air handler 120d. The air handler sections are mounted in a support frame 129d.

The data centre 101 comprises a weather-tight building envelope 103. The building envelope 103 comprises exterior walls 103a, 103b, and roof 103c. It will be appreciated that the building envelope may be of any suitable construction, such as sheet materials, e.g. cladding panels. As shown in Figures 1 and 2, the server racks 105, hot and cold aisles, cold air supply corridor 150b/c/d and air handling units 120b/c/d are all positioned within the building envelope 103. As will be appreciated from Figure 2, personnel can move between areas within the building envelope 103, such as between the cold corridor 150d, hot and cold aisles and air handler 120d (e.g. via air access doors 125d/126d/127d/128d) without having to exit the building, and thus without having to travel or work outside.

Figure 3 shows a further enlarged portion of the drawing of Figure 1, annotated with the same reference numerals as used in Figure 1. In Figure 3, a portion of a row of IT racks 105 is shown with a corresponding row of service cassettes 106 suspended above them. The service cassettes 106 are shown comprising air entrainment panels 107, electrical cable trays 108 and network cable trays 109 above the IT racks 105. Further suspended air entrainment panels 110 form the ceiling separating the cold corridor 150c from the warm air plenum 153c. The air entrainment panels 107 of the service cassettes 106 segregate the hot and cold aisles. Openings 119 in panels 107 are provided to accommodate services passing between hot and cold aisles. The openings include adjustable covers to maintain air segregation between aisles. Drop-rods 112 fastened to brackets 111 -24 -support the service cassettes 106. Further drop-rods 113 secured to slot channel beams (not shown in Figure 3) fastened to brackets 111 support the air entrainment panels 110.

Figure 4 shows an end cross-sectional view through a portion of the data centre 101 of Figure 1, labelled with the same reference numerals as used in Figures 1-3. As in Figure 1, Figure 3 shows services level 102a and data levels 102b-d. The view of Figure 3 cuts across cold aisles 151 and hot aisles 152.

Figure 5 shows an enlarged view of a portion of Figure 4. As shown in Figure 5, service cassettes 106 are suspended from brackets 111 mounted on the structure of the building 104.

Figure 6 shows a side cross-sectional view through a portion of the data centre 101 of Figure 1. Features corresponding to those shown in Figure 1 are labelled with the same reference numerals. The view of Figure 6 cuts through the interior of the building 101 and also through an exhaust conduit 201 that extends across levels 120a-d. The exhaust conduit 201 is defined on three sides by exterior walls of the building envelope 103 (the exhaust conduit positioned outside the envelope 103), and on a fourth side by cowling 202. The exhaust conduit provides a space for receiving warm air ejected from the building envelope 103 through controllable exhaust vents 203b/c/d, which vents are positioned in the envelope 103 adjacent warm air return spaces 154b/c/d, respectively, above air handling units 120b/c/d, respectively (not shown in Figure 6 -see Figure 1). During operation of the data centre 101, warm air from warm air return space 154b/c/d is ejected from the envelope 103 through controllable exhaust vents 203b/c/d into the exhaust conduit 201. As shown in Figure 6, the building envelope 103 forming three sides of the exhaust structure 201 comprises weather-tight cladding panels 204. The exhaust conduit 201 directs warm air upwards towards the roof of the building 101, thereby avoiding inadvertent mixing between warm air exhausted from the building and fresh ambient air being drawn into the building for use as fresh cooling air.

Figure 7 shows an end elevation of the data centre 101 of Figure 1, showing controllable ambient air intakes 205b/c/d arranged on the external sides of the building envelope, and exhaust conduits 201 enclosed by cowling 202. During operation of the data centre 101, ambient air from outside the data centre 101 is -25 -drawn in through controllable air inlets 205b/c/d into mixing chambers 155b/c/d, and then into air handling units 120b/c/d, respectively (not shown in Figure 7). As shown in Figure 7, ambient air is thus drawn into the end of the data centre, while warm air ejected into exhaust conduits 201 is directed upwards and out of the top of the building.

Figure 8a shows a plan view of data level 102c of the data centre 101 of Figure 1, labelled with the same reference numerals as used in Figures 1-7 (except that, for clarity, the 'c' suffix is omitted). In the floorplan shown in Figure 8a, the IT area of the data level includes cold aisles 151, hot aisles 152, rack storage areas accommodating racks 105, and connecting corridor 114 (which links cold aisles 151 together). In use, cooling air is provided by air handler units 120, which deliver cooling air into one side cold corridor 150, which transports and distributes cold air to cold aisles 151 through vented access doors 116, which provide controlled fluid communication and personnel access between the cold corridor 150 and cold aisles 151. Examples of vented doors are disclosed in W02010139921 (Bripco BVBA), the contents of which are incorporated herein by reference. Personnel doors 117 provide access to hot aisles 152 from the cold corridor 150, while also maintaining air segregation between the cold corridor 150 and the hot aisles 152. It will be appreciated that personnel doors could additionally or alternatively be provided at the other end of hot aisles 152. Warm air is ejected from the building through controllable exhaust vents 203, and fresh ambient air is drawn in through controllable intake vents 205. The cross sectional area of each exhaust conduit 201 is at least 14m2, the depth of each conduit being around 7m (the depth being the distance from cowling 202 to building envelope 103) and the width of each conduit being around 2m (the width being the distance from building envelope 103 on one side to building envelope 103 on opposing side in the case of exhaust conduits 201 sandwiched between air handling units 120, and distance from building envelope 103 on one side to cowling 202 on the opposite side of the exhaust conduit 201 in the case of outermost exhaust conduits 201). Thus, the minimum internal dimension of each exhaust conduit 201 is 2m.

Figure 8b shows the plan view of Figure 8a, annotated to indicate the positions of the views of Figures 1, 4 and 6. Line A-A indicates the position of the -26 -view of Figure 1. Line B-B indicates the position of the view of Figure 4. Line C-C indicates the position of the view of Figure 6. Line D-D indicates the position of the view of Figure 7.

Figure 9 shows a side cross-sectional view through a portion of a multi-level data centre 9001 according to another embodiment of the invention. The data centre 9001 of Figure 9 is similar to the data centre 101 of Figure 1, except that the air handling units (not shown in Figure 9) are located outside the building envelope. For simplicity, features of the data centre 9001 of Figure 9 corresponding to those of data centre 101 of Figure 1 are labelled with the same reference numerals as used for data centre 101 of Figure 1. The view of data centre 9001 of Figure 9 is similar to the view of data centre 101 of Figure 6, and cuts through the interior of the data centre 9001 and also through an exhaust conduit 901 that extends across levels 120a-d. The exhaust conduit 901 is defined on one side by exterior wall 903a of the building envelope 903 (the exhaust conduit 901 positioned outside the envelope 903), two sides by housings 950b/c/d of air handing units 120b/c/d (not visible in Figure 9, but behind outer walls 950b/c/d respectively), and one side by cowling 902. The exhaust conduit provides a space for receiving warm air ejected from the data centre through controllable exhaust vents 203b/c/d, which vents are positioned in the housings 950b/c/d adjacent warm air return spaces 154b/c/d, respectively, above air handling units 120b/c/d, respectively (not shown in Figure 9). During operation of the data centre 9001, warm air from warm air return space 154b/c/d is ejected from the data centre through controllable exhaust vents 203b/c/d into the exhaust conduit 901. The exhaust conduit 901 directs warm air upwards towards the roof of the data centre 9001, thereby avoiding inadvertent mixing between warm air exhausted from the building and fresh ambient air being drawn into the building for use as fresh cooling air. Access doors 925, 926, 927 and 928 on each data level provide personnel access to components of air handing units 120b/c/d (similarly to the access provided by doors 125, 126, 127 and 128 of data centre 101 shown in Figure 2) from the exhaust conduit 901 via exhaust conduit doors 960b/c/d (not shown in Figure 9 -see Figure 10). Open mesh flooring 970b/c/d divides the exhaust conduit 901 into regions corresponding to the data levels, allowing personnel to safely reach access doors 925, 926, 927 and 928 while also allowing exhaust air to -27 -flow upwards through the exhaust conduit 901. An open mesh floored gangways 980b/c/d are also provided adjacent the exhaust conduit 901 and air handling unit housings 950b/c/d outside the building envelope, providing external access to exhaust conduit doors 960b/c/d. The gangways 980b/c/d extend along the end of the data centre 9001, behind a decorative grill screen 990. Alternatively, exhaust conduit doors could be provided in the building envelope 903, providing direct access to the exhaust conduit 901 from inside the data centre building (e.g. from the cold corridor 150b/c/d).

Figure 10 shows an end cross-sectional view through the data centre 9001 of Figure 6, showing controllable ambient air intakes 205b/c/d arranged on the externally facing sides of the air handling unit housings 950b/c/d, and exhaust conduits 901 enclosed by cowlings 902. Also shown in Figure 7 are exhaust conduit access doors 960b/c/d in cowlings 902. During operation of the data centre 101, ambient air from outside the data centre 9001 is drawn in through controllable air inlets 205b/c/d into mixing chambers, and then into air handling units 120b/c/d, respectively (not shown in Figure 10). As shown in Figure 10, ambient air is thus drawn into the end of the data centre, while warm air ejected into exhaust conduits 901 is directed upwards and out of the top of the building.

Figure 11a shows a plan view of data level 102c of the data centre 9001 of Figure 1, labelled with the same reference numerals as used in Figures 9-10 (except that, for clarity, the 'c' suffix is omitted). In the floorplan shown in Figure 11a, the IT area of the data level includes cold aisles 151, hot aisles 152, rack storage areas accommodating racks 105, and connecting corridor 114 (which links cold aisles 151 together). In use, cooling air is provided by air handler units 120, which deliver cooling air into one side of the cold corridor 150, which transports and distributes cold air to cold aisles 151 through vented access doors 116, which provide controlled fluid communication and personnel access between the cold corridor 150 and cold aisles 151. Examples of vented doors are disclosed in W02010139921 (Bripco BVBA), the contents of which are incorporated herein by reference. Personnel doors 117 provide access to hot aisles 152 from the cold corridor 150, while also maintaining air segregation between the cold corridor 150 and the hot aisles 152. It will be appreciated that personnel doors could additionally or alternatively be provided at -28 -the other end of hot aisles 152. Warm air is ejected from the building through controllable exhaust vents 203, and fresh ambient air is drawn in through controllable intake vents 205. The cross sectional area of each exhaust conduit 901 is at least 14m2, the depth of each conduit being around 7m (the depth being the distance from cowling 902 to building envelope 903) and the width of each conduit being around 2m (the width being the distance between opposed outlet vents 205 in the case of exhaust conduits 901 sandwiched between air handling units 120, and distance from the outlet vent 205 to the cowling 902 on the opposite side of the exhaust conduit 901 in the case of outermost exhaust conduits 901). Thus, the minimum internal dimension of each exhaust conduit 201 is 2m.

Figure 11b shows the plan view of Figure 11a, annotated to indicate the positions of the views of Figures 9 and 10. Line C-C indicates the position of the view of Figure 9. Line D-D indicates the position of the view of Figure 10. A view taken at line B-B would be the same as the view of data centre 101 in Figure 4.

Figure 12 illustrates steps of a method according to an embodiment of the invention, the method being a method of cooling servers in the multi-level data centre 101 of Figures 1-8b. In step X01, cooling air is transported along an airflow path leading from the air handling units 120 to servers in racks 105 via the cold air supply corridor 150 and the cold aisles 151, and from the servers to the air handling units 120 via the warm area comprising hot aisles 152 and warm air plenum 153. The airflow path is located within the building 101. In step X01, air is expelled from the interior of the building 101 into exhaust conduits 201 (via exhaust outlets 203), and conveyed upwards to the roof 103c of the building 101. Exhaust air from data levels 102b/c/d is combined in each exhaust conduit 201.

Figure 13 illustrates steps of another method according to an embodiment of the invention, the method being for constructing the multi-level data centre 101 of Figures 1-8b. In step X11, each data level 102 b/c/d is created by defining on respective floors of the building: (1) 20 rack storage areas, each arranged to accommodate a row of 31 server racks, and separating alternating hot aisles 152 and cold aisles 151; and (2) a cold air supply corridor 150 for transporting cold air from air handling units 120 to the cold aisles 151 and for providing personnel access to the cold aisles 151. The cold air supply corridor 150 is in fluid communication with the -29 -cold aisles 151 through vented doors 116 arranged along a first side of the cold air supply corridor 150. In step X12, the method comprises installing on each floor a plurality of air handling units 120 for supplying cooling air to the servers via the cold aisles 151. Each air handling unit comprises an adiabatic cooling unit. In step X13, the method comprises forming within each data level 102 a warm air return path for transporting warm air from the hot aisles 152 to the air handling units 120. The warm air return path comprises warm air plenum 153. In step X14, the method comprises forming in the building envelope 103 at each data level: (1) a plurality of intake openings each comprising a controllable intake vent 205 for admitting ambient air into the data centre 101, and (2) a plurality of outlet openings each comprising a controllable outlet vent 203 for exhausting air out of the data centre 101. In step X15, the method comprises forming outside the building envelope 103 exhaust conduits 201 for receiving warm air from two controllable outlet vents 203 of each of the levels 102. Each exhaust conduit 201 has four sides, one formed by cowling 202 and the other three by exterior walls of the building envelope 103.

Whilst the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein.

Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, whilst of possible benefit in some embodiments of the invention, may not be desirable, and may therefore be absent, in other embodiments.

Claims

-30 -Claims 1. A multi-level data centre comprising a plurality of data levels, wherein each data level accommodates: at least fifteen rack storage areas positioned on a floor, each rack storage area being arranged to accommodate at least ten server racks each capable of accommodating at least twenty servers; a plurality of cooling units for cooling the servers, each cooling unit optionally comprising an adiabatic cooling unit; wherein the data centre comprises on each level: a plurality of intake vents for admitting ambient air into the data centre, wherein each intake vent is in fluid communication with a cooling unit, and a plurality of warm air outlets for expelling air out of the data centre via at least one exhaust conduit, wherein said exhaust conduit is in fluid communication with at least one warm air outlet of each of at least two data levels; and wherein the multi-level data centre has a building envelope and the air handling units are positioned outside the building envelope.
2. A multi-level data centre comprising a plurality of vertically separated levels; wherein each level is positioned between a floor and a ceiling, and is bounded by at least one exterior wall of a building, and wherein each data level comprises: at least fifteen rack storage areas positioned on the floor, each rack storage area being arranged to accommodate at least ten server racks each capable of accommodating at least twenty servers; at least three cooling units for cooling the servers, each cooling unit optionally comprising an adiabatic cooling unit; wherein the plurality of air handing units are located outside the at least one exterior wall of the building; and wherein the multi-level data centre comprises at least one exhaust conduit arranged to receive air from at least one warm air outlet of each of the plurality of levels.
3. A multi-level data centre comprising a plurality of data levels, wherein each data level accommodates: at least fifteen rack storage areas positioned on a floor, each rack storage area being arranged to accommodate at least ten server racks each capable of accommodating at least twenty servers; a plurality of cooling units for cooling the servers, each cooling unit optionally comprising an adiabatic cooling unit; wherein the data centre comprises on each level a plurality of intake vents for admitting ambient air into the data centre, wherein each intake vent is in fluid communication with an air handling unit, and wherein each intake vent is arranged to admit ambient air through a side of the data centre; wherein the data centre comprises at least one exhaust conduit for expelling air out of the data centre, wherein said exhaust conduit is in fluid communication with at least one outlet of at least one data level and is arranged to expel air through a top of the data centre, and wherein each data level warm air outlet communicates with at least one exhaust conduit.
4. A multi-level data centre comprising a plurality of data levels, wherein each data level accommodates: at least fifteen rack storage areas positioned on a floor, each rack storage area being arranged to accommodate at least ten server racks each capable of accommodating at least twenty servers; a plurality of cooling units for cooling the servers, each cooling unit optionally comprising an adiabatic cooling unit; wherein the data centre comprises on each level a plurality of intake vents for admitting ambient air into the data centre, wherein each intake vent is in fluid communication with a cooling unit; -32 -wherein the data centre comprises at least one exhaust conduit for expelling air out of the data centre, wherein said exhaust conduit is in fluid communication with at least one warm air outlet of each of at least two data levels, and wherein said exhaust conduit has a minimum cross-sectional area of at least 2m2.
5. A multi-level data centre according to claim 1 wherein the multi-level data centre is also according to any one or more of claims 2 to 4, or a multi-level data centre according to claim 2 wherein the multi-level data centre is also according to any one or more of claims 1, 3 or 4, a multi-level data centre according to claim 3 wherein the multi-level data centre is also according to any one or more of claims 1, 2 or 4, or a multi-level data centre according to claim 4 wherein the multi-level data centre is also according to any one or more of claims 1 to 3.
6. A multi-level data centre according to any preceding claim, wherein said exhaust conduit comprises at least one personnel access door providing personnel access to the at least one exhaust conduit.
7. A multi-level data centre according to any preceding claim, wherein said exhaust conduit comprises an upper region above a lower region, the upper region being divided from the lower region by open mesh flooring for supporting personnel, optionally wherein the at least one exhaust conduit comprises an upper region personnel access door and a lower region personnel access door.
8. A multi-level data centre according to claim 6 or claim 7, wherein said at least one exhaust conduit provides personnel access to at least one side of an air handling unit via at least one said exhaust conduit personnel access door, optionally wherein said at least one exhaust conduit provides personnel access to at least one component of an air handling unit via at least one said exhaust conduit personnel access door.
9. A multi-level data centre according to claim 8, wherein the at least one exhaust conduit provides personnel access to at least one side of each of multiple air handling units arranged on multiple data levels via at least one exhaust conduit personnel access door.
10. A multi-level data centre according to any preceding claim, wherein each intake vent is arranged to admit ambient air horizontally, and each exhaust conduit is arranged to transport air vertically and optionally to expel air vertically.
11. A multi-level data centre according to any preceding claim, wherein the intake vents and said at least one exhaust conduit are arranged so that: said ambient air drawn into the data centre is drawn in from an ambient environment beside the data centre, and (ii) said air expelled from the data centre is expelled to an ambient environment above the data centre.
12. A multi-level data centre according to any preceding claim, wherein the intake vents are controllable intake vents, and the warm air outlets each comprise a controllable outlet vent.
13. A multi-level data centre according to any preceding claim, wherein the data centre comprises at least three data levels, and wherein said at least one exhaust conduit (preferably each exhaust conduit) is arranged to receive air from warm air outlets of each of at least three data levels.
14. A multi-level data centre according to any preceding claim, wherein: said at least one exhaust conduit is positioned between a first cooling unit of a data level and a second cooling unit of said data level; and/or said at least one exhaust conduit communicates with at least two warm air outlets of one data level, optionally wherein at least one of said outlets is positioned on a first side of the exhaust conduit and another of said -34 -outlets is positioned on a second side of the exhaust conduit, optionally wherein the first and second sides are opposed sides.
15. A multi-level data centre according to any preceding claim, wherein the cooling units are air handling units for supplying cooling air to servers via a cool air zone, and the data centre comprise a warm air zone for transporting warm air from servers to at least one of: (i) the air handling units and (ii) the warm air outlets.
16. A multi-level data centre according to claim 15, wherein each data level comprises a plurality of controllable recirculation vents for controlling admission of warm air from the warm air zone to one or more of the air handling units.
17. A multi-level data centre according to claim 15 or claim 16, wherein: the rack storage areas separate alternating hot aisles and cold aisles; each cool air zone comprises a cold air supply corridor for transporting cold air from the air handling units to the cold aisles and for providing personnel access to the cold aisles, the cold air supply corridor being in fluid communication with the cold aisles through openings arranged along a first side of the cold air supply corridor; each warm air zone comprises a warm air return path for transporting warm air from the hot aisles to the air handling units; and, the plurality of air handing units are positioned along a second side of the cold air supply corridor opposite the first side.
18. A multi-level data centre according to claim 17, wherein the warm air return path is a warm air plenum that extends above the cold air supply corridor and the cold aisles, optionally wherein the warm air plenum is segregated from the cold air supply corridor and the cold aisles by a plurality of air entrainment panels suspended from a ceiling structure.
19. A multi-level data centre according to any preceding claim, comprising at least four, optionally at least five, data levels.
20. A multi-level data centre according to any preceding claim, comprising a plurality of server racks located in the rack storage areas, each server rack accommodating at least 20 servers.
21. A method of cooling servers in a multi-level data centre according to claim 20, wherein the method comprises operating the cooling units to cool the servers, and expelling warm air from multiple levels of the building into said at least one exhaust conduit, wherein the exhaust conduit conveys exhausted air upwards to or near the roof of the building.
22. A method according to claim 21, wherein the cooling units are air handling units and the method comprises operating the air handling units to produce cooling air, transporting the cooling air along a cool airflow path leading from air handling units to the servers via a cold air supply corridor and cold aisles, and transport warm air along a warm airflow path leading from the servers to the air handling units and/or to warm air outlets.
23. A method of making a multi-level data centre comprising a plurality of data levels, the method comprising: creating each data level by defining on a floor of a building at least fifteen rack storage areas, each rack storage area being arranged to accommodate a row of at least ten server racks each capable of accommodating at least twenty servers; installing on each floor a plurality of cooling units for cooling the servers, each air handling unit comprising an adiabatic cooling unit; and, forming an exhaust conduit for receiving air from at least one data level warm air outlet; wherein: -36 -i. the exhaust conduit is in fluid communication with at least one warm air outlet of each of at least two data levels, the data centre has a building envelope, and the cooling units are positioned outside the building envelope; ii. the data levels are vertically separated data levels, each level is formed between a floor and bound by at least one exterior wall of a building, and the cooling units are located outside the at least one exterior wall of the building; iii. each exhaust conduit is in fluid communication with at least one warm air outlet of at least one data level, wherein each data level warm air outlet communicates with an exhaust conduit, and wherein each exhaust conduit is arranged to expel air through a top of the data centre; and/or iv. the exhaust conduit is in fluid communication with at least one warm air outlet of each of at least two data levels, and the exhaust conduit has an internal cross-sectional area of at least 2m2.
24. A method according to claim 23, comprising forming at each data level: a plurality of intake openings for admitting ambient air into the data centre, each preferably comprising a controllable intake vent, wherein each intake opening is in fluid communication with an air handling unit; and a plurality of warm air outlet openings for expelling air into an exhaust conduit, each preferably comprising a controllable outlet vent.
25. A method according to claim 23 or claim 24, wherein the data centre is according to any one of claims 1 to 20.