Geothermal FAQ

Geothermal heating and cooling (also called GeoExchange) uses the constant temperature of the earth — about 55°F in Massachusetts — to heat and cool buildings. A geothermal system circulates fluid through underground pipes (ground loops), absorbing heat from the ground in winter and rejecting heat into the ground in summer. A heat pump inside the building concentrates this energy to provide comfortable temperatures year-round.

Residential geothermal systems typically cost between $25,000 and $55,000 before incentives depending on home size, borehole footage, and system design. In Massachusetts, Mass Save rebates provide $15,000 (up to $25,000 for income-eligible households) plus 0% HEAT Loan financing up to $25,000 and tradeable AECs, substantially reducing net homeowner out-of-pocket costs. Commercial and institutional systems vary by scale. GDNE provides free, no-obligation estimates for every project.

The two main types are: Standing Column Wells (open-loop systems that circulate natural groundwater) and Closed Loop Systems (sealed HDPE piping installed in vertical boreholes). Standing column wells are often preferred in New England due to the region's favorable bedrock geology. GDNE has extensive experience with both system types and will recommend the optimal solution for your site.

Absolutely — geothermal is actually ideal for New England. Because the system uses the constant 55°F underground temperature, it performs efficiently regardless of how cold it gets above ground. Unlike air-source heat pumps that lose efficiency in extreme cold, geothermal maintains consistent performance even during the harshest New England winters.

Drilling and ground loop installation typically takes 1–3 days for a residential project and 1–3 weeks for larger commercial installations. The complete process — from site assessment through final commissioning — usually spans 4–8 weeks depending on project complexity and permitting requirements.

Most homeowners see payback within 4–7 years through dramatic reductions in winter heating fuel and summer cooling bills. When factoring in Mass Save rebates up to $25,000, 0% HEAT Loan financing up to $25,000, and ongoing Alternative Energy Credits (AECs), monthly operational savings immediately exceed loan payments.

The indoor heat pump unit typically lasts 25+ years — significantly longer than conventional furnaces (15–20 years) or air conditioners (12–15 years). The underground ground loop piping is rated for 50+ years. This makes geothermal one of the most durable HVAC investments available.

Modern geothermal drilling uses compact rigs that minimize site disruption. Our licensed operators carefully plan well locations to avoid utilities, septic systems, and landscaping. After installation, wellheads are typically flush with the surface and the affected area is restored. Most homeowners are surprised by how little evidence of drilling remains.

Geothermal systems require minimal maintenance — significantly less than conventional HVAC systems. There's no outdoor compressor, no combustion, and no fuel deliveries. Annual checkups are recommended, similar to any HVAC system, but there are far fewer components that can fail.

Yes. GDNE regularly installs geothermal systems in existing homes. The ground loop is drilled on your property, and the indoor heat pump connects to your existing ductwork or can integrate with radiant floor heating. A retrofit typically requires only a small amount of indoor space for the heat pump unit.

Yes — this is one of geothermal's biggest advantages. The same system provides heating in winter and air conditioning in summer by simply reversing the heat exchange process. Many systems also provide domestic hot water as a bonus, further reducing your energy costs.

Massachusetts homeowners qualify for up to $25,000 in whole-home Mass Save cash rebates, 0% interest HEAT Loan financing up to $25,000, and ongoing Alternative Energy Credits (AECs). Commercial, campus, and municipal projects qualify for the federal Section 48 Investment Tax Credit (ITC) of 6% to 30%+ plus accelerated MACRS depreciation and Section 179D deductions. Contact GDNE for a detailed incentive analysis.

GDNE, a division of T.J. Ogden Co. (Ogden Wells), has been drilling geothermal borefields across New England since 1997. With 45+ years of drilling engineering experience, licensed drillers, HDPE Fusion certification, and IGSHPA accreditation, we bring unmatched expertise. Our portfolio includes Harvard University, Nichols College, hospitals, and hundreds of residential installations throughout Massachusetts.