Concerning Automotive Thermoelectric Generators (ATEG), analysts IDTechEx enter 2015 with the view that thermoelectric energy harvesting will be on production hybrid electric on-road vehicles from 2018. It will be commonplace on hybrids in 2020 and almost entirely to charge the battery, or increasingly supercapacitor or supercabattery used for power. As explained in the new report, Energy Harvesting/ Regeneration for Electric Vehicles Land, Water & Air 2015-2025 www.idtechex.com/ehforev there will be little use on wireless devices through the vehicle because the necessary heat differences will not exist where most of these are positioned.
Logically thermoelectric energy harvesting should go on large vehicles first including military ones because the increased efficiency does not just save money, it eases the problems of fuel logistics (the US Military plans 70% reduction in fuel consumption for this reason) and security of propulsion.
Dr Peter Harrop, Chairman of IDTechEx says, “Hybrids will outsell pure electric vehicles until 2030.” He adds, “Pure EVs do not have adequate heat differences for thermoelectrics, so the market for thermoelectrics, once established, will be ongoing. We expect thermoelectrics to remain the only form of energy harvesting where the material cost is not the largest component of cost though work is ongoing to make these elements by additive processes instead of the current micro-machining.” One implication is that the materials can be profitable due to limited price sensitivity and breakthroughs such as less toxic materials and formable materials will be greatly valued. The addressable automotive market is therefore primarily hybrid cars for charging – around 9 million units in 2025 if paybacks are established.
More speculatively, conventional cars, which will still be the majority of cars made in 2025, are incorporating more and more energy harvesting to reduce fuel usage since the starter heating Ventilating Air Conditioning HVA batteries can be loaded at up to 500W in them these days. Some stop-start is electromechanical energy harvesting and some alternators work backwards in an equivalent of regenerative braking in EVs. It is possible, but by no means demonstrated, that thermoelectric harvesting on all those hot conventional engines may prove viable adding tens of millions to our figure for addressable market in 2025.