Focusing on the generation of low carbon, cheaper electricity from on-site waste heat, Heatcatcher has developed a process — based on Organic Rankine Cycle technology — for use where fossil fuels have been combusted, or from a carbon neutral heat source such as a biomass boiler or biofuel generator.
Up to 30 per cent of the heat generated by a sites can be lost to waste heat, says Heatcatcher, a new company formed by Sussex-based HVAC inspection and survey specialist Efficient Air. Traditionally sites have captured this waste to provide hot water for site services — however, there is often much more hot water generated than demand, which means that the captured waste heat is again wasted.
Heatcatcher's technology allows generation of cheaper, carbon-free, electricity from this waste heat, to match electricity demand. The Heatcatcher system takes the form a heat exchanger (evaporator) retrofitted to the exhaust of the waste heat emitting machine. The heat is transferred through a thermal liquid pumped to the Heatcatcher Generator Unit, heating and pressurising an organic gas, and forcing it to expand through a micro turbine, out putting electricity. This expanded gas then needs to be cooled to a liquid through the condenser unit to start the cycle again.
Performance figures based on 8520 annual operating hours show that a waste heat input power of 380kW can produce 426,000kW/hrs of carbon-free electricity annually and save 234 tonnes of CO2. A waste heat input power of 7600kW produces 8,520,000kW/hrs of electricity and saves 4686 tonnes of CO2.
