Earlier this year, Sen. Mike Nofs, chairman of the Senate Energy & Technology Committee, invited Michigan electric co-ops to weigh-in on the state’s current energy statutes and plans regarding renewable energy, contained in House Bill 438.

Representing the co-ops, Art Thayer, energy efficiency programs director for the Michigan Electric Cooperative Association (MECA), testified on Sept. 2, with a particular focus on geothermal energy.

“We believe that geothermal heat pumps can play a significant role in helping the state comply with the new clean air rules recently finalized by the Environmental Protection Agency under Sec. 111(d) of the federal Clean Air Act,” Thayer said.

The EPA’s rules are changing Michigan’s energy landscape, he added, and geothermal heating and cooling systems are a vital source of clean, efficient and renewable thermal energy.

After explaining how geothermal heat pumps (GHPs) operate­ – by using solar energy stored just below the earth’s surface to heat, cool and provide hot water to residential, commercial, and industrial buildings – Thayer emphasized that once installed, geothermal ground loops last indefinitely, and the inside unit has a lifespan of 25+ years.

A fully scalable technology that is effective for both homes and commercial buildings, GHPs use 25 to 50 percent less electricity than conventional heating or cooling systems. “And, according to the EPA, they can reduce energy consumption—and corresponding emissions—by 44 to 72 percent compared to traditional heating and cooling equipment,” he said.

The efficiency and renewability of GHPs has been officially recognized by the administration in Washington, D.C., with its Executive Order, “Planning for Federal Sustainability in the Next Decade,” Thayer added. The Order is meant to cut federal greenhouse gas (GHG) emissions by 40 percent over the next decade, from 2008 levels. The EPA states on its Energy Star website that GHPs are the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available.

The Order also recognizes GHPs in its mandate that the government increase the share of electricity it consumes from renewables to 30 percent, and increase energy efficiency and renewable thermal energy use by federal buildings.

Geothermal heat pumps are easily applicable to many sections of the Executive Order as an efficiency tool and renewable source for saving energy, reducing costs, and curbing carbon emissions by federal buildings across the nation, Thayer reported. “Increased GHP installations and uses can bring those benefits to Michigan, too, especially under the new EPA rule 111(d) clean air requirements.”

The EPA released its Clean Power Plan (CPP) on Aug. 3, setting state?specific targets for CO2 emissions from existing coal?fired plants. The rule allows flexibility in meeting the desired emissions reductions nationwide, including renewable energy and efficiency, and encourages using energy efficiency as a major way for states to comply with the new rules.

However, to ensure that the full potential of GHPs is realized toward the goal of carbon reductions, Thayer emphasized that the EPA must recognize that GHPs may increase electricity use, but at the same time replace heating and cooling systems that rely on inefficient fuels (propane, fuel oil).

Other important considerations and tools that can help the EPA and states attain rule 111(d) requirements include:

  • All electric utilities, in conjunction with their power suppliers, will need a suite of resources and robust energy efficiency programs to meet the new, very stringent federal greenhouse gas (GHG) rules outlined by the EPA;
  • Energy efficiency offsets must be implemented under the carbon reduction rules, specifically, the benefits of renewable thermal energy technologies as a way to avoid power generation and therefore cut emissions. GHPs provide both renewable energy and efficiency offsets
  • Michigan should recognize the GHP’s ability to avoid thermal energy produced by fossil fuels as an emissions reduction tool;

With proper market?based incentives and other promotional efforts by utilities and the state, GHPs can make a significant contribution to cutting greenhouse gas emissions, Thayer explained. A typical 3-ton residential GHP can reduce summer peak demand by about 2 kW. Taken times 500 homes equipped with GHPs, it gives a peak power demand reduction of 1 MW. “Geothermal systems are an important tool in our toolbox that utilizes clean and renewable energy, reduces greenhouse gas emissions, reduces energy waste, and reduces summer peak demand on Michigan’s electric systems.”

Leaving a final thought, Thayer said: “What are the total greenhouse gas emissions of a geothermal system that uses electricity generated from a hydro, solar, wind or nuclear power plant? The answer is a simple one. It’s zero.”