GB2484099A

GB2484099A - Heating system including an electrical immersion heater powered by a photovoltaic panel

Info

Publication number: GB2484099A
Application number: GB1016355.8A
Authority: GB
Inventors: Matthew Lee
Original assignee: FAITH LOUISE Ltd
Current assignee: FAITH LOUISE Ltd
Priority date: 2010-09-29
Filing date: 2010-09-29
Publication date: 2012-04-04
Also published as: GB201016355D0

Abstract

The heating system comprises a hot water cylinder 18 having a first heat input coil 16 arranged to be supplied, in use, with heated fluid via an input circuit 12 connected to a boiler 10; an electrical immersion heater 30; and a photovoltaic panel 32 operable, in use, to supply electrical power to the immersion heater. A second heat input coil may be provided in the cylinder, the second coil being connected to a further renewable heat source, such as liquid-based solar. An output coil 24 may be provided in the cylinder to permit the extraction of heat for use in a space heating circuit 20 including radiators or an under-floor heating circuit 22. Electrical power derived from the photovoltaic panel may be diverted, in whole or in part, to one or more electrical circuits by a control panel 34. The heating system removes the need for the installation of additional pipe-work between the photovoltaic panel and the cylinder.

Description

I

HEATING SYSTEM

This invention relates to a heating system, for example for providing space heating and/or hot water within a domestic building. Although suitable for use in such applications, the invention is not restricted to such use, For example, it could be used in industrial settings.

A typical domestic heating system comprises a gas or oil fired boiler operable to heat a transfer fluid, such as water, which is pumped around a boiler circuit. The boiler circuit is typically connected, via suitable valves to a spacing heating circuit so that the heat output from the boiler can be used for space heating purposes. The boiler circuit is also typically connected, via suitable valves, to a heat exchange coil provided in a hot water cylinder so that the heat output from the boiler can be used to provide hot water by heating the water stored within the cylinder.

Increasingly, there is a need to make use of renewal energy resources, for example solar energy, wind energy, or the. like, in order to reduce reliance upon oil or gas and thereby preserve these resources as well as reducing the emission of carbon dioxide and other waste products and to reduce cost. Traditionally, in order to make use of, for example, solar energy, a building has been provided with two separate heating and! or hot water circuits or systems, one using the boiler and the other using a solar panel as the heat source. Such systems are inconvenient.

A system is known in which a hot water cylinder is provided with an additional input heat transfer coil connected to a fluid based solar panel. In such an arrangement, the heat output from the solar panel is used to raise the temperature of the water within the cylinder, and a boiler is used to supplement the solar input when the temperature and! or volume of hot water achieved relying upon the solar panel alone is lower than desired.

Such a system has the advantage of being relatively simple, but still requires pipework to be installed between a solar panel located, typically, on the roof of a building, and the hot water cylinder. The installation of such pipework may be impractical or inconvenient in some buildings.

It is an object of the invention to provide a heating system of simple and convenient form and in which renewable energy may be used.

According to the present invention there is provided a heating system comprising a hot water cylinder having a first heat input coil arranged to be supplied, in use with heated fluid via an input circuit connected to a boiler unit, an electrical immersion heater, and a photovoitaic panel operable, in use, to supply electrical power to the immersion heater By using an electrical immersion heater and photovoltaic panel to provide a renewable energy heat input to the hot water cylinder, it will be appreciated that the need to provide additional pipework to connect a fluid based solar panel to the heating system can be avoided.

If desired, a second heat input coil may be provided in the hot water cylinder to allow heat input to the hot water cylinder from another source.

If desired, an output coil may be provided in the hot water cylinder to permit the extraction of heat energy therefrom. For example, heat energy extracted from the hot water cylinder could be used by a space heating system. In such a system, both hot water and space heating may be supplied; at least in part, by the use of solar power.

The invention will further be described by way of example, with reference to the accompanying drawings in which; Figure 1 is a diagram illustrating a heating system in accordance with one embodiment of the invention; and Figure 2 is a view similar to figure 1 illustrating an alternative embodiment.

Referring to Figure 1 there is illustrated a heating system comprising a gas or oil fired boiler 10 operable to supply heated fluid, typically water although other fluids could be used, through a boiler circuit 12 and suitable control valves 14 to a first heat exchange coil 16 of a hot water cylinder 18 raising the temperature of the water located therein. Suitable sensors are provided whereby a control unit can cause the operation of the valves 14 and boiler 10 to be changed when a desired volume ol water has reached a desired temperature.

The valves 14 also control the application of the healed fluid to, in this case, a radiator circuit 20 and an underiloor heating circuit 22 so as to provide space heating to the building.

In addition to the coil 16, the hot water cylinder 18 contains a second, output heat exchange coil 24 operable to permit heat energy to be extracted from the hot water within the cylinder 18, the extracted heat energy being applied to the radiator circuit 20 and! or underiloor heating circuit 22 when desired. The extraction and supply of heat energy in this manner is controlled, in use, by the control unit controlling the operation of a pump 26 and valve 28.

In accordance with the invention, the hot water cylinder 18 is further provided with an immersion heater 30 arranged to be supplied with electrical power by a photovoltaic panel 32 via a suitable control unit 34. The panel 32 will typically be roof mounted and angled so as to maxim ise the collection of solar energy. The control unit 34 may be operable to convert the output of the panel 32 to a suitable input for the heater 30, and in this regard may include suitable transformer means. It may further be connected to electrical circuits provided within the building so as to permit the electrical energy generated by virtue of the operation of the panel 32 to be diverted, in whole or in part, to other circuits of the building if or when desired.

In use, electrical energy generated as a result of the operation of the panel 32 can be supplied to the heater 30 and used to raise the temperature of the water within the. cylinder 18. Depending upon factors like the outside temperature and weather, the time of day and the time of year, the output of the panel 32 and operation of the heater alone may be sufficient to raise the water temperature to a desired level to provide the hot water and! or space heating requirements of the building, in which case the boiler 10 will be inoperative. Where the hot water and! or space heating requirements cannot be met by the solar energy alone, then the boiler 10 can be used to supplement the solar input. Depending upon requirements, the space heating circuits may be supplied either directly from the boiler circuit 12 or via the second coil 24. In these modes of operation, energy consumption by the boiler 10 is reduced as at least part of the heating requirement is met using solar energy.

As mentioned hereinbefore, the control unit 34 may be operable to further supply electrical energy to other electrical circuits. Thus, for example, the heater 30 may be provided only with the energy "/eft over" once the electrical demands of the other circuits have been met. In this mode of operation, it will be appreciated that the water within the cylinder 18 acts as an energy store in which such "left over" energy can be stored. However, other operating modes are also possible.

A wide range of photovoltaic panels are available that would be suitable for use as the panel 32. For example, it is thought that a suitably positioned array of panels covering an area of around 20m2 could produce an electrical output power of approximately 3kW, and such a system would be able to provide a worthwhile electrical supply to a typical immersion heater. Whilst such an arrangement is possible, it will be appreciated that the invention is not restricted in this regard. For example, a number of immersion heater designs are available which would operate satisfactorily whilst requiring a lower, for example 2kW, supply. If such an arrangement is used, then it will be appreciated that a smaller area of panels, or an alternative design of panel could be used. Furthermore, even if a lower energy level can be derived from the panels than would be required to heat the water within the cylinder 18 to a desired temperature, it will be appreciated that any increase in temperature resulting from the operation of panels and immersion heater results in a reduction in the need to operate the boiler 10 and so will create fuel consumption and cost savings.

Although in the description hereinbefore the boiler 10 is described as being of oil or gas fired form; it will be appreciated that other forms of boiler or heater may be provided to serve the function of the boiler 10, and they may be powered from other energy sources. For example, electrical, solid fuel or heat pump powered arrangements could be used.

Figure 2 illustrates a modification to the arrangement of Figure 1. In the arrangement of Figure 2 the cylinder 18 is provided with a third, supplementary input heat exchange coil 36 connected to another renpwable energy or heat source. For example, it may be connected to a liquid-based solar panel (not shown). In use, the coil 36 and heater 30 are both used to raise the water temperature within the cylinder 18 using renewable energy sources. As described hereinbefore, the boiler 10 can be used to provide a supplementary input when required.

Although not illustrated, an additional coil to permit extraction of heat energy may be provided, or the second coil may be omitted if there is no requirement to extract heat energy. A number of other modifications or alterations may be made to the arrangements illustrated without departing from the scope of the invention.

Claims

CLAIMS: 1. A heating system comprising a hot water cylinder having a first heat input coil arranged to be supplied, in use with heated fluid via an input circuit connected to a boiler unit, an electrical immersion heater, and a photovoltaic panel operable, in use, to supply electrical power to the immersion heater.
2. A system according to Claim 1, wherein a second heat input coil is provided in the hot water cylinder to allow heat input to the hot water cylinder from another source.
3. A system according to Claim I or Claim ? further comprising an output coil, provided in the hot water cylinder, to permit the extraction of heat energy therefrom.
4. A system according to Claim 3, wherein heat energy extracted from the hot water cylinder is used by a space heating system or an underfloor heating system.
5. A system according to any of the preceding claims, further comprising control means whereby electrical power derived from the photovoltaic panel can be supplied to one or more other electrical circuits within a building.
6. A heating system substantially as hereinbefore described with reference to the accompanying drawings.