This commentary is by Norm Etkind of Woodbury, who has extensive experience in the alternative energy and efficiency fields. He has certifications from the Association of Energy Engineers in sustainable development, energy management, building commissioning, and masters-level energy auditing.
What’s missing from the public discourse around the clean heat bill is how essential and beneficial the use of wood fuels in Vermont is.
The bill, S.5, also known as the Affordable Heat Act, is how Vermont will be seeking to eliminate our reliance on fossil fuels to heat our buildings while reducing costs, providing resiliency, and making sure that the needs of lower income Vermonters are addressed.
Those goals will not be met without the planned use of Vermont’s wood resources.
Over the years, the value of Vermont’s forests as working lands has been recognized and aided through the current use program, the Vermont Housing and Conservation Board, and other mechanisms. Key to government strategies was to ensure that forestry operations were well planned to provide a sustainable forest resource into the future.
We have been very successful in achieving a thriving forest resource while providing employment, lumber for furniture and construction, and using low-grade wood for fuel.
Having a market for the lower-value trees is an essential part of good forest management. It is important to remove “weed” trees to help preferred ones thrive for the same reason you weed a garden. A thriving forest will absorb more carbon dioxide from the air. An older forest contains more sequestered CO2 than a younger, faster-growing forest. However, the younger sustainably managed forest will absorb more carbon from the atmosphere.
Our trees are a valuable renewable resource. They are part of a continuing carbon cycle where the basic building blocks of water and carbon dioxide are forced through the absorption of energy from sunlight and the process of photosynthesis to create our trees.
When used as fuel, the process is reversed, the energy is used, and the CO2 is released back into the air and available to the next tree to repeat the process. In old-growth forests, when trees die through natural processes, CO2 and methane are products of decomposition that are also released back into the atmosphere.
Vermont’s Comprehensive Energy Plan acknowledges the availability of fuel from sustainably managed forests to provide about a third of our building heat. The Affordable Heat Act includes wood fuels as a source to displace fossil fuels.
But why is it “essential” to meeting the goals of the Act?
After performing the most important methods of addressing our use of fuel — operating our buildings correctly, reducing heat loss, and other cost-effective strategies — Vermont winters require the use of energy to provide a living environment.
One key way of providing that heat is with cold-climate heat pumps. This is an advanced technology that relies upon moving the available heat in the outside air into the building. They do this very efficiently at moderately cold temperatures. But they lose efficiency when there is less heat in the outside air to work with. During very cold temperatures, they do not perform better than standard baseboard electric heat or plug-in electric heaters.
New installations of cold-climate heat pumps that I’m familiar with install electric baseboard heat as a backup when there isn’t an alternative heating system. Some cold-climate heat pumps have electric resistance elements built in to perform the backup function.
This dynamic creates a very serious problem when there is widespread adoption of cold-climate heat pumps. The use of electricity is not constant throughout the day or the season. The most difficult aspect of our use of electricity is satisfying peak demand. During that period, special generation resources are brought into play that are used rarely but need to be available. Currently they are primarily fired by oil, natural gas, and nuclear resources and are very expensive to operate.
The peak power occurs in the winter when people get home from work, and it is dark and cold. With the addition of hundreds of thousands of heat pumps in Vermont, a tremendous load will be placed on generation resources, as well as the grid and distribution utilities to provide the peak power needs.
Or, the peaks could be ameliorated using wood fuels in efficient EPA-certified cordwood or pellet stoves as backup to heat pumps or by heating more of our buildings primarily with wood. Central automated wood systems now operate very efficiently with minimal particulate (smoke) generation.
Also, resiliency is important. When we experience power outages, a common event in Vermont, wood fuels can provide the needed building heat that is otherwise unavailable in an all-electric home. Battery storage may help for a short outage but is useless for an extended one. A large generator can be installed for this purpose but has significant cost and use disadvantages.
No method of heating our homes will be perfect and the use of wood fuels is not for everyone. However, its traditional use as a fuel in Vermont, coupled with the advances in wood-burning systems for cordwood, pellets and chips, will help us meet our climate goals and this benefit is recognized in the Affordable Heat Act.
