National Grid Proposes Networked Geothermal

National Grid is proposing to build a geothermal network that could be mixed use like the one depicted above, or it could test performance with more homogeneous building types.
May 25, 2021

After the Department of Public Utilities rejected their first attempt, National Grid is back with a new proposal to build a geothermal network. It’s described in Docket No. 21-24 for those of you who want to read along. Their new proposal has many good details.

Their new proposal: 

  • Looks at how a geothermal network can replace leak prone pipes.
  • Whether the geothermal network can move all a building’s energy needs to electricity.
  • Tries to meet the needs of a district where the population density varies.
  • Enables geothermal for low income households.

Over five years National Grid will learn how a geothermal network works, how it cuts emissions, how heating options can be made more sustainable, and whether this safer low-emitting system can be their business model for the future. They are also emphasizing the customer experience and attitudes to find out how best to promote geothermal networks.  

These are terrific goals. 

One not-so-good part is that the monthly customer rates seem very high for the first two years, especially for low-income households. These families will pay $112.50 per month. 

Even though the rate falls to $3 per month for years three through five, $112.50 a month isn’t decreasing the energy burden for these families, especially when their electric bill will increase on top of it from their heat pump. We look forward to hearing what the Department of Public Utilities decides. 


Last fall, when National Grid first requested permission to pilot a geothermal network, the Massachusetts Department of Public Utilities rejected their proposal. Because their proposal was similar to the one recently proposed by Eversource, the Department asked that they reconsider their request.