Les Otten

I believe the state of Maine and Efficiency Maine need four key efficiency goals when examining our heating needs: efficiency of the envelope, efficiency of the appliance, cost efficiency and carbon efficiency.

I appreciate that a core goal of Efficiency Maine is to ensure Mainers are heating their buildings as efficiently as possible. I feel strongly that this initiative needs to consider all perspectives, capturing a full complement of decarbonization incentives across Maine and the Northeast.

In short, we need to walk, talk, think, and chew gum at the same time.

Envelope efficiency: Buildings need good insulation and good windows, regardless of if the project is new construction or a renovation. This commonsense approach should always preempt other initiatives targeting technological efficiency and/or efforts to lower the building’s conditioning carbon intensity. We thus support Efficiency Maine as it considers additional incentives to improve the envelopes of new homes and the renovation of older buildings.

Mechanical efficiency: Heating appliances need to be efficient in their operation. Best-in-class technologies can demonstrate efficiency ratings (heat pumps, pellet boilers, etc.) in excess of 85%. Expecting this performance ensures that the vessel is making the most use of that fuel to heat and provide domestic hot water (in the case of wood pellet systems) and not wasting a precious commodity.

Cost efficiency: By design, heat pumps are more efficient than conventional resistance electric heating. However, Mainers can attest to the fact that electric rates can be inconsistent. Compounding this issue is the fact that air-source heat pumps progressively loose efficiency as ambient temperatures drop; the colder it gets the more electricity the heat pump consumes to deliver the same warmth.


It is necessary to recognize that as temperatures fall, heat pumps degrade into the same cost efficiency as electric baseboards. Worse, many heat pumps are simply not designed to operate below certain temperatures without a backup heating source, building owners may be facing a total loss of heat … just when they need it the most.

A single solution for home heating and the provision of domestic hot water is clearly preferable to reliance on multiple backups/systems. While heat pumps are good for warming a home, wood pellets are simply better for heating; Maine’s winters are cold. Modern wood pellet heat is local, it’s 100% renewable, and it’s available across New England — allowing those dollars spent on heating to stay within the local economies where the fuel is consumed.

Carbon efficiency: As we seek to combat climate change it is imperative that we consider the carbon intensity of our choices. Wood indisputably boasts the best carbon footprint of any widely available heating energy source. This undeniable truth stems from the fact that wood pellets are composed of biogenic carbon (unlike geologic carbon) assembled as sawmill residues, low grade forest products, and arboricultural waste wood. It is a simple and efficient use of the resources Mainers trust while both meeting decarbonization goals and stretching heating dollars.

That said, modern wood pellet heat is only one answer to a large problem. Using less electricity than a standard No. 2 heating boiler, these systems also protect the grid from being overtaxed — particularly at times when homes need the most heat. When it’s very cold in the dead of winter and it’s dark out, the New England grid can’t produce renewable electricity, so it reverts to fossil fuels. ISO New England publishes extensive data which show where electricity is generated and what happens when a winter storm forces the grid to hit peak levels.

With these four key efficiency goals in mind and proper incentives, Maine has the ability at its fingertips to meaningfully decarbonize home heating, save Mainers dollars on heating fuel, and ensure those dollars don’t get exported out of state.

Leslie B. Otten is a founder, owner and chief executive officer of Bethel-based Maine Energy Systems, the largest wood pellet central heating system manufacturer in North America.

Only subscribers are eligible to post comments. Please subscribe or login first for digital access. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.