Celebrating World Geothermal Energy Day

By Emily Lambert-Davis, Member, Southeastern Pennsylvania Group

Last month Geodelphia celebrated World Geothermal Energy Day (WGED) with a rally at Philadelphia City Hall. The purpose of WGED is to celebrate geothermal energy and the people that make it happen, showcase projects around the world, and highlight its benefits. Geodelphia was started by members of Philadelphia’s Ready for 100 team. Speakers at our rally included new city council member Nina Ahmad, Walter Tsou from Physicians for Social Responsibility, Flora Cardoni from PennEnvironment and Pamela Darville from POWER.

So why is it important to include geothermal energy in our clean energy toolbox?  

1. It is not intermittent but draws on a constant source of energy.  

2. A ground source heat pump uses about 30% less energy than an air source heat pump. In extreme heat and cold, air source heat pumps decrease in efficiency. As we move to electrify everything, and it gets hotter, this energy savings will help to reduce the stress on our electric grid.  

3. Geothermal is underground so it is unseen and leaves the surface of the land fully available for other uses.  

4. Geothermal does not require batteries – the ground below our feet stores the energy.  

5. Geothermal provides healthier indoor (and outdoor) air quality.  

6. Finally, a geothermal heat pump system is cost effective over the life of the system.

Then why aren’t we all using it? The primary reason is the cost of drilling a geothermal well field. The Pennsylvania German Society installed it in their 140-year-old building because they wanted cooling and heating that was sustainable and cost effective in the long term. The only air conditioning they had was in smaller rooms. They drilled 23 wells under their parking lot. Bartram’s Garden wanted to have clean energy that did not affect the look of the garden. And, in fact, it made it better because visitors are not disturbed by the sight or sound of the air conditioners as they wander in this historic garden. Geothermal energy is much easier to install in new construction. The geothermal wells heating and cooling the Kensington High School for Creative and Performing Arts are under the athletic field, but also in other new projects that wells can be drilled under the building.  

The problem in Philadelphia is that most homeowners/building owners don’t have enough land to drill the holes. The Friends Center on Cherry Street drilled some of their holes under the sidewalk. Another problem is that, for most homeowners, the installation cost is too high. Networked geothermal is a solution, and it is one of the suggestions in the Philadelphia Gas Works (PGW) Business Diversification Study done by the Office of Sustainability and PGW in 2019. The City signed the Ready for 100 pledge to convert to all clean energy by 2050. With buildings contributing up to 70% of our city’s carbon footprint and thousands of gas leaks in the city, it seems to us that PGW could spend some of the 8 billion dollars it plans to spend to fix leaks and begin installation of a geothermal network.

There are many networked geothermal systems in the United States, but most of them are on university and business campuses. The largest is actually a planned community near Austin, Texas, called Whisper Valley where the utility bills of residents are about 80% less than for traditional homes. The homes are heated and cooled using ground source heat pumps powered by the solar panels on their roofs. In Framingham, Massachusetts, an energy utility (Eversource) is installing the first networked geothermal system that will be owned and operated by a utility company. With the plan to electrify everything, using geothermal heating and cooling could save the grid.

Geodelphia thinks the solution is to create a geothermal utility company. The company builds and maintains the infrastructure and the property owners pay to use it. We also think it makes sense for PGW to be that company – Philadelphia Geothermal Company instead of Philadelphia Gas Company – still PGW.

This blog was included as part of the December 2023 Sylvanian newsletter. Please click here to check out more articles from this edition!