Thermal Energy Recovery
There are a number of companies developing methods for thermal energy recovery. For a hybrid vehicle, these technologies are drawing increasing attention. For the traditional vehicle, only 15-30% of fuel energy is converted to useful work. Approximately 40% is lost to exhaust heat and 30% is lost to engine coolant heat. Capturing even 10% of the waste heat with a thermal energy recovery system would yield system efficiency gains as high as 20 to 40%.
A few of these companies and their technologies are listed below.
ThinGap Automotive LLC is developing a lightweight cost effective design that functions with the vehicle’s current lubrication and cooling systems.
There are multiple forms of turbo generators. The typically version show for automotive use consists of 1/2 of a typically turbocharger. Rather than powering a compressor to force more air and fuel into the pistons, the turbine powers an alternator. The alternator produces electrical energy for onboard electrical systems, or a hybrid drive.
The disadvantage of the current turbo generators is that the required high speed profile of the turbine has led to a cost ineffective alternator and mating features. There are currently no known cost effective turbo generators for a hybrid vehicle.
Controlled Power Technologies is developing micro-hybrid technologies in order to reduced costs. This includes a stop-start device, electric supercharging and an exhaust gas regeneration device as shown to the left.
Thermoelectric Waste Energy Recovery Systems
Advances in Thermoelectric Generator (TEG) efficiencies have prompted a number of developments in automotive waste heat recovery. Companies such as BMW, Cummins and even the DOE are actively developing such technologies. Fuel economy gains of 5 - 10% have been demonstrated with a number of vehicles.
Waste Heat Recovery - Our Approach
With as many large companies and acadamic centers working on this problem, you are likely wondering why we at howtobuildahybrid.com, are even working in this area. We realize that it is highly unlikely that we will out engineer these other groups. Our best option is to become a marketing tool for one of the successful ventures by showcasing their device on our vehicle. However we do have a unique approach and maybe, just maybe it will work.