What is Geothermal?

A natural and renewable resource, geothermal energy is heat from the earth. The sun heats the earth to a nearly constant 45-70 degrees year round. Geothermal energy can be harnessed through heating and cooling systems to warm a home in the winter and cool it in the summer.

How does geothermal heating and cooling work?

Geothermal heating requires a looped well system installed just below the surface of the earth. A water solution flowing through the well’s piping in the ground absorbs heat from the ground in winter and transfers it to a geo-exchange system inside the building. There, the heat is concentrated and transferred to air circulating through the interior to provide warmth. In summer, the process is reversed. The system extracts heat from the interior air and transfers it to the ground by way of the ground loop piping.

Inside the house, the geothermal heat pump uses a refrigerant to heat the air inside the home during the winter, and in the summer it extracts heat from the air inside the home.


Benefits of Geothermal

An environmentally friendly form of energy, geothermal eliminates the use of fossil fuels. Geothermal customers typically cut their energy consumption by 20-15% and save up to 50% on water heating bills. Since it can be used for both heating and cooling, one unit will replace your furnace and air conditioner. New federal tax credits in support of energy efficiency exist today that can help pay for your geothermal system.

Accredited Geothermal Installation & Service

Responding to the call for energy efficiency, GWW helps to reduce your energy bills and your carbon footprint. As accredited Standing Column, Closed-loop and Open-to-recycle geothermal well contractors, we are able to make the best use of the earth’s energy..

When it comes to geothermal, we go beyond what traditional water well contractors can do. We have developed proprietary technology to reduce risk, lower costs and maximize energy efficiency for our geothermal customers.

Standing Column Wells

More Info

What is a Standing Column well?

A Standing Column well (SCW) is a traditionally constructed water well with a submersible pump system. SCWs are constructed similar to a standard water supply well. Water is pumped from the well, through the heat pump and is returned to the opposite end of the well. When operating in the heating mode, the heat pump extracts heat energy from the water, reducing its temperature, before returning it to the well. Solar stored heat energy in the ground naturally flows from the bedrock into the water to warm it back up before it is recycled back through the heat pump.

standing column well

GWW is the only water well contractor and geo-exchange installer in Maine with the knowledge, skill, and ability to install a Standing Column well and pump system, which will provide geo-exchange for geothermal heating and cooling.

Closed Loop Wells

More Info

What is a Closed-loop well?

A Closed-loop well is a borehole with two parallel high-density polyethylene pipes (HDPE) grouted its full length. Typically there are two or more Closed-loop wells piped together. A water based glycol solution is pumped through the Closed-loop wells to the heat pump, which extracts heat energy from the fluid, dropping its temperature. When this cold fluid is returned to the Closed-loop well, heat energy in the ground naturally flows through the grout and HDPE pipe and into the fluid, warming it back up.

closed loop well

Here is a diagram of a typical Closed- loop Well geothermal system utilizing a reverse return piping layout.

Open-to-Recycle Systems

More Info

What is an Open-to-recycle well?

An Open-to-recycle geo-exchange well typically involves two shallow, high yield wells. A submersible pump is set into one well, which pumps water from that well through the geothermal heat pumps. All of the water is then discharged back into the aquifer in the second well. This well can also be used to supply domestic water in addition to geothermal.



Here is a diagram of an Open-to-Recycle geothermal well system. The water is pumped from one well up through the geothermal heat pump and then discharged into a second well in the same aquifer. This requires two high yield wells and is the most efficient geothermal system.

Installation & Service

More Info

Accredited Geothermal Well Contractors

Our skilled and knowledgeable contractors are fully accredited for the installation and service of all geo-exchange systems – Standing Column Well, Closed-loop, and Open-to-recycle.

Standing Column Well (SCW) Design Tool

At Goodwin Well & Water, our engineers have developed a proprietary software – the only one of its kind – to achieve optimal efficiency and performance in Standing Column Wells for traditional water wells and geo-exchange systems. This software performs the complex set of calculations required to arrive at the optimal design for each residential SCW, taking into account unique characteristics and requirements of each customer’s individual situation.

Other Services

Well Drilling

Water that just works.

Pump Systems

Water supply that you can count on.

Water Quality

Know your water quality.


2282 Auburn Road
PO Box 661
North Turner, ME 04266

Call Us

Phone: 207.224.7861
Fax: 207.224.7174

Join our Mailing List