With a $2-million grant from the California Energy Commission (CEC), Berkeley Lab is partnering with Alphabet Energy to create a cost-effective thermoelectric waste heat recovery system to reduce both energy use in the industrial sector and electricity-related carbon emissions.
ICF International estimates that such a system could save California 3.2 million megawatt-hours per year in energy while also increasing electrical reliability. The funding comes from CEC’s Electric Program Investment Charge (EPIC) program, which funds clean energy innovation to reduce pollution, foster economic development, and meet the state’s climate goals.
Industrial facilities, such as power plants, cement plants, mining and manufacturing facilities, and oil and gas operations have more than 763 megawatts (MW) of electricity-generating potential from waste heat in California, and national potential is approximately 15,000 MW. However, most current thermoelectric materials are limited by several factors, including high cost, low efficiency, and the inability to operate reliably at temperatures above 400 degrees Celsius.
The new Berkeley Lab project, co-led by Prasher and Vi Rapp, a mechanical research scientist in the Energy Technologies Area, is working to overcome these barriers. In collaboration with Alphabet Energy, they will develop a cost-effective process for creating an advanced thermoelectric material constructed from silicon nanowire arrays.
Commercially available thermoelectrics achieve less than 5 percent efficiency in converting heat to electricity. The technology has already seen some market traction in the oil and gas and automotive industries.
Alphabet Energy is a Hayward, California-based startup that launched in 2009 using nanotechnology licensed from Berkeley Lab. They are developing advanced thermoelectric materials based on silicon nanowires with conversion efficiencies of 10% or greater and the ability to operate at temperatures up to 800 degrees Celsius.
The higher operating temperature also opens up new possibilities, such as increasing the power produced from capturing high-temperature waste heat from gas flares.
The CEC funding will enable Berkeley Lab and Alphabet Energy to develop a prototype device and validate its performance for high temperature heat-to-electricity conversion.