Zeyneb Magavi's mission is to spread the word about the potential of geothermal energy networks in a transition to clean energy that everyone can afford. Photo: Courtesy HEET
Beneath our feet, the earth’s surface warms and cools with the seasons. But lower down, soil and rock stay at a constant temperature – in Massachusetts, 55 degrees.
According to Zeyneb Magavi, this simple geological fact is a grand opportunity to shift into a new clean energy age, tackling climate change and lowering energy costs all at the same time. Magavi is the executive director of HEET, a Boston-based nonprofit (and a CLF partner) dedicated to transforming the way we heat and cool buildings. Magavi sees geothermal networks linking hundreds of homes and businesses through pipes snaking deep underground as part of “an ethical and efficient thermal energy transition.”
She recently visited CLF’s Boston office, where she spoke about the promise and potential of all the warmth stored underground. Below, we’ve adapted her remarks for length and clarity into an abridged Q and A.
CLF: You believe that we’re wasting the tremendous amount of geothermal energy stored in the earth that could be used to heat our homes.
Magavi: In the past 50 years, our earth absorbed, as heat, over 600 times the energy all humanity uses in a year – thanks to climate change! Add to that the heat, or thermal energy, that we waste (think combustion, sewage, and data centers), and the scale of the problem is even bigger, right? The world around us – the ground, the rivers, the sea – is too warm.
So, let’s take the enormity of the thermal energy problem and turn it into an enormous opportunity. We can stop producing waste heat and we can draw down the excess heat by sourcing our thermal energy from the world around us.
CLF: How does that work?
Magavi: Geothermal heat pumps use the shallow surface of the earth that stays in the ambient temperature range to move heat into and out of our bedrock, using it like a battery. This is far more efficient than moving heat into and out of the air. That’s because air doesn’t store a lot of heat, even though it’s what we feel.
CLF: HEET proposes that gas utilities, with millions of miles of aging and leaking gas pipes laid down under streets, replace those old pipes with water-filled geothermal pipes. Those warmed pipes would transfer that warmth to ground-source heat pumps designed to both heat and cool homes. In 2017, you approached the utilities about this idea. What was the reaction?
Magavi: We had some really interesting conversations. Because it turns out that utilities of all stripes plan in decades. So, one of them went first, Eversource. Last June, they cut the ribbon on the first geothermal network built by a gas utility that moved over 130 customers (located in Framingham, Massachusetts) onto geothermal energy for all their heating and cooling. That project [in which a gas utility built a geothermal network to transition from gas] is the first of its kind to our knowledge in the world.
CLF: What are the benefits of geothermal over gas?
Magavi: We easily check off high safety, high security, and 100% combustion-free as soon as the electric grid is combustion-free. But on day one, when a geothermal system gets switched on, it’s a more than 60% drop in carbon dioxide emissions equivalent. Reliability and resiliency are built into the design. It is much lower maintenance than the gas system.
It’s also scalable and adaptable. You can add customers onto or off of it and interconnect it to grow it, which is what’s happening next in Framingham.
Also, equitable access is fundamental to the utility model. If you have a utility, it should provide access whether you’re a renter or a low-income ratepayer or whatever.
If we use geothermal heat pumps for 68% of our heat pump installs in Massachusetts, we will drop our electric load by 34%, according to Oak Ridge National Labs. If we do that across the country, we will save $1.7 trillion in net present value by 2050.
And just to take it local, the Framingham project has electrified all heating and cooling for all those customers, including a school, fire station, and some commercial buildings. And they project that they will have lowered the electric load for the neighborhood.
CLF: What’s next in HEET’s geothermal journey?
Magavi: HEET has been really pleased to be awarded a Department of Energy grant to lead the design of the expansion of that first project together with Eversource and the City of Framingham as participants. We completed the design and were recently awarded Phase 2 of this Department of Energy funding opportunity, allowing us to move forward with construction, and, of course, also depending on the approval of our Department of Public Utilities here in Massachusetts. But it is ready to grow, and most importantly, Eversource Gas is ready, too. They see the opportunity this technology can provide their company, their workforce, and their customers. Here in Massachusetts, there is now a whole pipeline of projects and communities excited to move forward.
CLF: There seems to be momentum around geothermal. You have said eight states have passed gas-to-geothermal laws and are moving forward with demonstration projects like that in Framingham. So, what’s slowing down the adoption of geothermal networks?
Magavi: A bunch of barriers exist, and one of them is there is not a sufficient geothermal drilling workforce.
We’re very, very limited. I would say we don’t have enough geothermal drilling workforce to meet the construction timelines within a reasonable budget just for all the schools that want to have geothermal energy in Massachusetts. To address this we partnered with industry organizations, including the new Geothermal Drilling Association, to develop an 80-hour curriculum and launch a first cohort of geothermal driller technicians out into the workforce to spend the required three years learning from licensed drillers.
CLF: What’s next for geothermal?
Magavi: Geothermal energy is an extraordinary opportunity hiding in plain sight, right beneath our feet. Technological advances and a revolutionized business model coupled with the long-standing efficiency, safety, and affordability of geothermal heating and cooling means this may well be what keeps your home comfortable in the near future.
This is one in an occasional series on New England’s energy innovators.
