GB2381377A - Thermoelectric power generation device - Google Patents

Abstract

A Seebeck effect power generation device comprises a heat conductive base 11 which is heated by a heat source 12, a plurality of thermoelectric modules 14 separated by insulating layers 16 (eg high density foam) and a heat sink 13. The base 11 may be in contact with an engine block or cylinder head of an internal combustion engine, may have heat conveyed to it by a heat pipe, or may be heated by solar energy. The heat sink 13 may have fins which are cooled by an air flow. The thermoelectric modules 14 comprise banks of thermocouples (eg bismuth-telluride, bismuth-antimony, silicon-germanium) and the modules 14 may be connected in series or parallel to form an array having positive and negative electrical connections 17. The device may be used to charge a battery.

Description

<Desc/Clms Page number 1>

ELECTRICAL POWER GENERATION DEVICE Background of the Invention The following invention relates to the conversion of otherwise wasted heat energy into useful electrical energy. More particularly, though not exclusively, the invention relates to equipment including an array of banks of thermocouple devices attached to an engine block or cylinder head of an internal combustion engine and having an electrical output for charging an automotive battery.

An enormous amount of heat energy generated by internal combustion engines is wasted to atmosphere. Excess mechanical energy of an internal combustion engine is used to drive an alternator which charges the automobile's battery. However, heat radiated or conducted from the cylinder head, engine block and exhausted system is released to the atmosphere, thus contributing to known environmental problems, without being exploited for useful conservation of energy.

Object of the Invention It is the object of the present invention to provide a means of converting waste heat energy or heat potential across an interface into a useful electrical potential difference.

<Desc/Clms Page number 2>

Disclosure of the Invention There is disclose herein electrical power generating equipment including a generally planar heat conductive base for intimate physical contact with a heat source and a heat sink over the base that is arranged to be exposed to a flow of air, including an array of banks of individual thermocouple elements, each bank extending between the base and the heat sink, such that an electrical potential is generated across each bank when a temperature difference exists between the base and the heat sink.

Preferably, the heat source is an engine body.

Preferably, the heat sink includes fins.

Preferably, the fins are located in an area of cool air flow.

Preferably, electrical conductors are attached to the array of banks of thermocouple elements, the electrical conductors serving to charge a battery.

Preferably, a regulator is attached to one or both of the electrical conductors to prevent over-charging of the battery.

<Desc/Clms Page number 3>

Brief description of the drawings A preferred form of the present invention will r. ow be described by way of example with reference to Fig. 1 which is a schematic cross-sectional elevation view of an electrical power generating device.

Detailed description of the preferred embodiment In Fig. 1 there is schematically depicted an electrical power generating device 10 including a generally planar heat conductive base 11 for intimate physical contact with a heat source 12. A heat sink 13 has a number of cooling fins 14 attached thereto.

Between the heat sink 13 and base 11 there is provided an array of banks of thermocouple elements (Peltier, thermocouple devices etc) 14 and heat capacitance/conductor blocks 15. Located inbetween the banks of thermocouple elements 14 and capacitance/conductive blocks 15 are insulating layers

16.

Connected to the array of banks of thermocouple devices 14 are positive and negative electrical conductors 17.

The exact configuration of the heat sink 13 depends on

<Desc/Clms Page number 4>

the particular application's anticipated temperature conditions.

The insulating layers 16 might be formed of high density foam or other insulative material. The exact choice of material depends on the intended environmental temperature conditions.

The heat capacitive/conductive blocks 15 might be made of aluminium or another suitable good thermally conductive material. The typical thickness of these blocks might range from 0 mm (i. e. no blocks) to 80 mm or more depending on design parameters.

The thermocouple elements 14 might be connected in serious or parallel. The elements might be bismuthtelluride. However, bismuth-antimony might be suitable in low temperature conditions (40-120 C). Silicongermanium might be suitable for high temperature conditions over 5000C for example.

A flow of Air might be directed over the cooling fins either directly or by way of ducting.

The base 11 might be permanently secured to an engine block or cylinder head for example, or might be attached thereto by way of conductive adhesive or welding for example. Instead, it might be bolted or screwed to the

<Desc/Clms Page number 5>

heat source and have heat conductive paste applied between the heat source and the base. As yet a further alternative, the base 11 might be situated remotely from the heat source and might have heat conveyed to it for example by a heat pipe (a heat pipe is a construction of two pipes, one inside the other, where the space between the pipes is partially filled with a liquid that will evaporate at a chosen temperature if the inner tube is heated). When the vapour touches the cooler outside tube, the vapour will condense and revert to its liquid stage and evaporate again and so on). That is, the base might be located forward in the engine bay. For example, it might be fixed to part of the vehicle's radiator for example.

The electrical conductors might lead to a battery either directly or by way of conventional circuitry elements that might include a regulator. This will charge the battery instead of and/or in addition to a mechanically driven alternator or generator.

It should be appreciated that modifications and alternations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention. For example, instead of being adhered directly to a heat source generating excess or unwanted heat, the device could receive solar energy that might be amplified or concentrated by optical means.

<Desc/Clms Page number 6>

Also, the device is suitable for uses in any situation where there is a heat difference. For example, there is a heat difference between the passenger compartment of an air craft and the outside environment, particularly at high attitudes. Devices like that disclosed herein might be used to convert this otherwise waste heat potential into useable electrical energy.

Claims (6)

1. CLAIMS 1. Electrical power generating equipment including a generally planar heat conductive base for intimate physical contact with a heat source and a heat sink over the base that is arranged to be exposed to a flow of air, including an array of banks of individual thermocouple elements, each bank extending between the base and the heat sink, such that an electrical potential is generated across each bank when a temperature difference exists between the base and the heat sink.
2. 2. The equipment of claim 1 wherein the heat source is an engine body.
3. 3. The equipment of claim 1 wherein the heat sink includes fins.
4. 4. The equipment of claim 3 wherein the fins are located in an area of cool air flow.
5. 5. The equipment of claim l wherein electrical conductors are attached to the array of banks of thermocouple elements, the electrical conductors serving to charge a battery.
6. 6. The equipment of claim 5 wherein a regulator is attached to one or both of the electrical conductors.