What devices exist to convert heat energy into electricity?

Question

Obviously there are solar cells of various types, but is there anything else? What items have the smallest form factor?

Answer 1

Steam turbine generators:

Water is heated to produce steam.
The steam turns turbines that run magnetos that produce electricity.

Answer 2

Thermocouples are about the next best thing. They can be very small but the number of them needed could make the structure quite large. The "SNAP" generators used in past years in satellites were this type of device. It used nuclear material to produce heat which the thermocouples changed into electricity. Fuel cells also convert heat energy to electricity. Thermohydrodynamics is another way to use heat to make electricity. This is where a plasma is conducted down a channel with separated plates to collect the electrical charge. It does work, but not all that well right now since the plasma is quite corrosive to the metals. The others are right about solar cells, it is light that they use to make electrical energy, not heat. There is however, a solar cell being developed that will use both visible light, and infra-red, or "heat" to produce electricity.

Answer 3

Solar cells convert light to electricity. A steam turbine attached to a generator converts heat energy to electricity.

Answer 4

90 percent of the world's electricity is created by burning fossil fuels to create heat to spin a turbine that drives a generator. These methods have a 20% efficiency rate.

Thermoelectric converters use the Seebeck effect, which creates a voltage when two different metals are kept at different temperatures. They only have a 7% efficiency rate.

A more efficient method developed at MIT will use organic materials sandwiched between two metals at different temperatures. This method may one day be used to create small, low-cost power generators.

Answer 5

Fuel cell cars will probably be out sooner. No need to have pure hydrogen in storage. Some fuel cells can split the hydrogen off of easily obtainable hydrocarbons like methane or LPG. Since fuel cells are more than twice as efficient as internal combustion engines people will wonder how we ever got along with just having a 400 or so mile range before having to refuel.

Answer 6

Solar cells do not turn heat into electricty; they turn light into it. Excluding having heat run a turbine to run a generator, a thermocouple is about the next practical device.

Answer 7

Steam powered generator.

Answer 8

Nuclear power..allthough you may not want to attempt..

Answer 9

Thermocouples or any engine