Find the straight skinny on geothermal standards

We’ve gotten a lot of questions about how to determine minimum efficiencies for our new geothermal rebate. So here are the answers (and of course you’re welcome to contact us if you need more information).

We use the minimum efficiency number—not the average or a partial load number. Therefore, a system needs to meet the following minimum standard:

  • Closed loop: ?17 EER and ?3.6 COP
  • Open loop: ?21.1 EER and 4.1 COP

That minimum must be verified by the AHRI certificate that you include with an application, and it applies across the board—to new construction projects or to systems that are replacing electric resistance, propane, natural gas, or fuel oil systems.

We do realize that a unit may be running on partial load most of the time, but that won’t get your customers a rebate. To qualify, the unit must meet the full load rating above.

The federal government agrees, by the way. Its 30% tax credit minimums are the same as ours.

Get in touch if you have more questions about the geothermal rebate.