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A team of researchers developed a device that recovers energy from the heat lost in industrial processes.
Every year, energy equating to billions of barrels of oil is wasted as heat loss from machines in industrial processes. Recovering this potential could considerably reduce energy costs. This is what a team of scientists from Australia and Malaysia is trying to do, with an innovative system that is designed to maximize such recovery.
Heat can be transformed into electricity by devices called thermoelectric power generators (TEGs), which are made of materials that generate electricity when heat passes through them. There have been previous studies attempting to use TEGs to recover energy from the heat generated by car engines, woodstoves and refrigerators. However, the same problem kept coming up: TEGs can only convert a small amount of the heat they receive, and the rest is dissipated.
The researchers designed a system in which a TEG is inserted between two heat pipes, which are devices that can efficiently transfer heat. One pipe delivers heat to the TEG and the other collects the dissipated heat.
For two kilowatts of energy supplied to the system, researchers recovered approximately 1.35 kilowatts of heat: over 67% of the energy supplied. In addition, the TEGs generated 10.39 watts of electricity during the heat recovery process.
Both heat pipes and TEGs are passive devices that require no energy input besides the waste energy. The findings demonstrate that these simple devices can be used to generate electricity and at the same time make energy recovery more efficient. The work could provide the basis for future development of energy recovery systems on an industrial scale.
Source: Science Daily