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Energy & Environment

Geothermal pilot network offers model to scale up state emissions reductions

Inspecting a geothermal system in Massachusetts, which begins with the digging of deep bore holes and placement of pipes filled with water and other fluids connected to a heat pump. The process taps into the relatively constant temperature of the earth to heat and or cool buildings. Photo courtesy of Del. Lorig Charkoudian.

A bill making its way through the Maryland General Assembly is aimed at chipping away at carbon emissions as required by state law. The Climate Solutions Now Act of 2022 set in motion a mandate to cut greenhouse gas emissions by 60% by 2031 and to reach net-zero emissions by 2045.

Introduced by Del. Lorig Charkoudian (D-Montgomery) and crossed filed by Sen. Katie Fry Hester (D-Howard and Montgomery), House Bill 397, Working for Accessible Renewable Maryland Thermal Heat, or WARMTH Act, creates a pilot program that would establish networked geothermal projects in a handful of neighborhoods across the state.

Geothermal systems tap the relatively constant temperature of the earth six feet below ground to heat or cool a building, circulating water and other fluids like antifreeze through a network of deep pipes, connected to a heat pump.

A 2021 report by the Maryland Commission on Climate Change finds that residential and commercial buildings account for 13% the state’s carbon emissions.

WARMTH to underserved communities

According to the U.S. Energy Information Administration, geothermal heat pumps are the most energy efficient, environmentally clean and cost-effective energy systems for heating and cooling buildings.

Charkoudian says that while WARMTH largely targets low-income communities, its impact would reach beyond those underserved neighborhoods.

Networked geothermal as envisioned in a pilot program in Framingham, Mass. Image from Eversource.

“We’re [also] going to improve housing with efficient appliances, and weatherization, items provided through strategic use of [Inflation Reduction Act] funds,” she said. “That lowers the electric bill, not only for the people in the pilot, but when you electrify with more efficient systems like networked geothermal, then you avoid cost to the [electric] grid, and that benefits all ratepayers.”

At the fifth annual Sierra Club Legislative Summit in early January, Charkoudian said in the state’s race to decarbonize, the pilot would create a model for household electrification everywhere.

“And, it will first offer money to community organizers to reach out across the state to find neighborhoods where 200 people are willing to be part of this pilot,” she said.  “Then what happens is they engage with a local gas company, who with approval from the Public Service Commission [would] dig the geothermal [bore holes] and put the pipes in the ground.”

Utilities pay upfront costs

According to the bill, the utility would pay for the networked system, recovering expenses in the same way costs are recovered for gas pipelines, poles and wires, through rate cases at the PSC.

Charles Washington, vice president of governmental and external affairs for BGE, Maryland’s largest provider of electricity and natural gas, says Maryland is at a critical juncture where aging infrastructure must be replaced. He says the state’s STRIDE program allows BGE to accelerate replacement pipes for safety and environmental reasons.

“We have an obligation to provide a safe and reliable system to our customers,” he said. “For as long as customers are drawing on our natural gas system, it’s important that we make appropriate investments [and] that we’re addressing leaks providing a safe product.”

Jamie DeMarco, Maryland director of the Chesapeake Climate Action Network, agrees the infrastructure needs an upgrade.

“We need to replace old pipes, but let’s not replace them with new gas pipes, but instead with networked geothermal and get every house on that block, all electric,” he said.  “The [WARMTH] bill requires that each utility create a networked system, and we think once they do that, they’ll like it and do a lot more of them.”

In 2023 BGE filed a multi-year energy infrastructure investment plan with the PSC that advocates an integrated multi-system approach. “It’s important to recognize there will need to be a balance between the various sources of energy, [and] I think you can expect us being vocal about our support for piloting the [geothermal] technology,” Washington said.

Keep jobs in Maryland

Labor standards in the bill prioritize job security for current gas workers.

Brian Terwilliger, assistant business manager for IBEW Local 410, which represents 1,400 BGE workers, says the workforce is up to the task. “The skill set is already there. The operators are already there, the construction workers, the maintenance workers, the emergency responders are there to keep it safe and reliable, the outline is in place,” he said.

IBEW Local 410 Vice President Gerry Warner underscores their support.  “We think it is a big win for the state and for our members,” he said. “Whatever is coming in the future with other energy options, we think our workforce should be a part of it.”

Maryland is among several states eyeing the potential of networked geothermal. Last summer Charkoudian led a group that included representatives from Maryland gas utilities, labor unions and state agencies to visit geothermal projects in Massachusetts. She says analysis from there and other states, coupled with data required by WARMTH, is key to getting the energy mix right.

“The reason we need to do this as quickly as possible is that in the next couple of years we are going to be making some really big decisions about how we decarbonize as a state, and I want information about how this [networked geothermal] works,” she said.

A hearing on the Senate bill has been scheduled for Feb. 15 in the Committee on Education, Energy and the Environment, where Hester is a member. The House version will be heard on Feb. 22 in the Economic Matters Committee, where Charkoudian is a member. She says she is optimistic about its chances.

“I have worked with over 100 stakeholders over the last eight months to develop [WARMTH],” she said. “But that doesn’t mean it’s perfect. I’m always open to hearing additional feedback and amendments.”


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Geothermal pilot network offers model to scale up state emissions reductions