During my travels, I often see many sources of energy being wasted. This can be in the form of building air conditioners or refrigeration units that vent heat to the atmosphere, or even the heat given off automobile engines. It's always made me think there must be a way to efficiently recapture at least part of that heat and turn it back into useful energy.
Apparently I am not alone in my thoughts. ElectraTherm, Inc., announced the first commercial installation of their new "Green Machine", an electrical generator that recaptures waste heat and turns it into electricity. The generator was recently installed at Southern Methodist University in Dallas, Texas. The beauty of this system is that, since it uses heat from other systems that is normally wasted, no additional energy is required to generate electricity, making it a truly "zero emissions" power source.
According to the company's news release, the 50 kW generator has "exceeded expectations". The key to the new generator's success is the company's patented Twin Screw Expander, which improves the efficiency and cost of the unit enough to be commercially viable, a solution thus far eluding other similar generators using the Organic Rankine Cycle.