Skyline with HSC, WattTime, and Consumers Energy logos

Hemlock Semiconductor, Consumers Energy, and WattTime reduce grid emissions through industrial load shifting

 October 28, 2021 

Saginaw, Mich. and Oakland, Calif.—October 28, 2021—Today Hemlock Semiconductor Operations, LLC (HSC), a manufacturer of hyper-pure polysilicon for the electronic and solar power industries, announced it has collaborated with Michigan energy provider Consumers Energy and environmental tech nonprofit WattTime to reduce grid emissions through industrial load shifting. At full production, HSC is the largest single-site user of electricity in the state of Michigan and the largest customer of Consumers Energy.

HSC worked with WattTime to assess the ability to use WattTime’s Automated Emissions Reduction (AER) technology to adjust the timing of its flexible electricity demand to sync with moments of cleaner energy. In tandem, Consumers Energy developed a rate that included both real-time pricing and demand-based attributes to further encourage demand flexibility. Based on WattTime analysis, this industrial load shifting could help HSC reduce CO2 emissions by up to ~2,500 metric tons annually, equivalent to eliminating more than 6 million miles driven by a passenger car or not burning more than 2.7 million pounds of coal.

“We are proud of our ongoing sustainability efforts and are excited about how shifting some of our energy demand can further reduce emissions and help incorporate more renewables on Michigan’s grid,” explained Phil Rausch, Solar Commercial Manager at 

HSC. “Plus, as a member of the Ultra Low-Carbon Solar Alliance, we remain focused on doing our part to decarbonize all parts of the solar energy supply chain, including the polysilicon we supply to the solar industry.”

Industrial load shifting with a company like HSC can be a powerful tool for Michigan’s grid (which is part of MISO) as it rapidly transitions to higher amounts of renewable energy. In June 2021 Consumers Energy announced an updated plan to retire all coal-fired generation by 2025, 15 years ahead of its original schedule. This comes as part of Consumers Energy’s updated Clean Energy Plan, which calls for 1,100 MW of new solar capacity by 2024 and nearly 8,000 MW of new solar by 2040.

“Our work with HSC shows how energy-intensive customers can contribute meaningfully to our Clean Energy Plan while also keeping costs competitive,” said Brian Rich, Consumers Energy’s senior vice president of customer experience. “For example, as Consumers Energy adds new solar capacity to Michigan’s grid, HSC could be an important flexible demand anchor for incorporating that solar, especially with seasonal load shifting to help absorb solar generation in the spring and fall when residential and commercial electricity demand is lower.”

WattTime’s analysis went further, and found even greater emissions-reduction opportunities by applying HSC’s degree of industrial load shifting to other grids, such as California (CAISO) and the Great Plains (SPP). Industrial demand flexibility in these regions offer substantial emissions-reduction potential of up to 34% vs. baseline emissions associated with the shifted load, approximately 10x greater emissions savings on a percentage basis and 8x greater on an absolute emissions basis than what is achievable in the Great Lakes region (MISO) today. As more renewables are built in Michigan in the years ahead, we’d expect to see similar opportunities there for HSC and other industrial customers.

“Hemlock Semiconductor and Consumers Energy are showing how industrial loads can add needed flexibility to power grids, helping to reduce emissions and integrate more renewables in the process,” concluded Laura Corso, managing director of partnerships at WattTime. “What’s possible in Michigan currently is just the tip of the iceberg. Regions such as California and the Great Plains today show even greater emissions-reduction potential, and they reflect what will be possible in Michigan in the near future—sizable emissions reductions that accelerate the clean energy transition during this decisive decade of climate action.”

To learn more about the collaboration between Hemlock Semiconductor, Consumers Energy, and WattTime—and the emissions-reduction potential of industrial load shifting—please download their new joint white paper, Powering the Future: Harnessing Industrial Demand Flexibility to Reduce Emissions and Integrate Renewables (EXECUTIVE SUMMARY | FULL REPORT).


Hemlock Semiconductor is a producer of hyper pure polycrystalline silicon, providing the key feedstock for the semiconductor and photovoltaic industries. As the single largest consumer of electricity in the state of Michigan, HSC is dedicated to reducing its carbon emissions. HSC participates in existing market programs concerning MISO Demand Response and engages in load shifting in accordance with market programs and time of use pricing. Recently HSC's efforts were recognized as Project of the Year by the Michigan EIBC (Energy Innovation Business Council) for work in shifting electrical consumption from on-peak to off-peak periods, and the Michigan Department of Environmental Quality (DEQ) has also designated HSC as a Clean Corporate Citizen (C3). Learn more about HSC at

Consumers Energy, Michigan’s largest energy provider, is the principal subsidiary of CMS Energy (NYSE: CMS), providing natural gas and/or electricity to 6.8 million of the state’s 10 million residents in all 68 Lower Peninsula counties Learn more at

WattTime is an environmental tech nonprofit that empowers all people, companies, policymakers, and countries to slash emissions and choose cleaner energy. Founded by UC Berkeley researchers, we develop data-driven tools and policies that increase environmental and social good, including Automated Emissions Reduction and emissionality. WattTime is also the convening member and cofounder of the global Climate TRACE coalition. During the energy transition from a fossil-fueled past to a zero-carbon future, WattTime ‘bends the curve’ of emissions reductions to realize deeper, faster benefits for people and planet.