The PowerBlocks thermoelectric materials are p-type tetrahedrites and n-type magnesium silicide (Mg₂Si) which provide the average ZT of around 1—similar to that obtained by skutterudite (GM, Gentherm) and half-heusler (GMZ) materials used by the DOE Waste Heat 2 (WH2) projects, according to a recent US Department of Energy (DOE) technology assessment.

Tested in Alphabet Energy’s first product, the E1 Thermoelectric Generator (there are 32 PowerModules in an E1, which was introduced in October 2014), the PowerModule directly accepts exhaust heat with a temperature ranging from 350 – 600 °C and transforms it into DC electricity, delivering up to 850 watts of power.

The E1, packaged in a standard 20-foot sea container envelope, generates up to 25 kW_e per 1,000 kW_e engine—i.e., an implied efficiency of about 2.5%—saving 52,500 liters of diesel fuel per year, per engine. Compared to other waste heat recovery systems, the E1 requires only minor up front engineering scope and no operation by the customer. This makes it suited for remote and industrial applications where ongoing system support capacity is limited. Alphabet Energy has taken multiple orders for the E1, which has gone through extensive customer testing in the field.

As the E1 continues to prove valuable to customers in the oil & gas, mining and defense industries as they generate reliable remote power while also reducing fuel consumption, operating costs and carbon emissions, the PowerModule has gained market traction on its own. Alone, the PowerModule can be used on a passenger vehicle to reduce alternator loads and improve fuel efficiency, or scaled in multiples to increase energy efficiency for industrial furnaces at a steel manufacturing plant.

It has long been our goal to be known as the ‘Intel Inside,’ or in our case, the ‘Alphabet Inside’ of waste heat recovery. The scalable nature of the PowerModule enables both energy and design efficiency, bringing the benefits of waste heat recovery to even more markets. Now, almost any owner of exhaust heat can generate valuable electricity.

—Dr. Matthew Scullin, founder and CEO, Alphabet Energy

According to TechNavio, 20-50% of global industrial energy is wasted as heat. In the United States alone there is the potential to convert waste heat from more than 2,900 industrial sites into 14,594 MW of power.

Alphabet Energy leverages nanotechnology research from Lawrence Berkeley National Laboratory and Michigan State University and has more than 60 patents issued and filed.

Resources

• D.T. Crane, A. Lorimer, C. Hannemann, J. Reifenberg, L. Miller, M. Scullin (2015) “A System-Level Approach to Thermoelectric Material Property Optimization” Journal of Electronic Materials Volume 44, Issue 6, pp 2113-2117 doi: 10.1007/s11664-015-3679-7

• Saniya LeBlanc (2014) “Thermoelectric generators: Linking material properties and systems engineering for waste heat recovery applications,” Sustainable Materials and Technologies, Volumes 1–2, Pages 26-35 doi: 10.1016/j.susmat.2014.11.002

• Saniya LeBlanc, Shannon K. Yee, Matthew L. Scullin, Chris Dames, Kenneth E. Goodson (2014) “Material and manufacturing cost considerations for thermoelectrics,” Renewable and Sustainable Energy Reviews, Volume 32, Pages 313-327 doi: 10.1016/j.rser.2013.12.030