Last Updated: Jun 16, 2021
With winter just around the corner, many homeowners are looking for ways to cut back on their heating bills. Your actual heating load will ultimately depend on many factors. These factors include your home's size, your climate, the energy efficiency and thermal performance of your house, and the type of fuel you use. Homeowners in the United States pay an average of almost $600 per year to keep their homes warm.
You can do a variety of things to improve the energy efficiency of your home during the winter. For instance, schedule maintenance on your furnace or purchase a do-it-yourself weatherstripping kit to seal the gaps and cracks around your windows and doors. For a more detailed winter-readiness checklist for your home, check out this Rise article.
About 41 percent of new, single-family homes built in 2018 included gas, electric, or wood-burning fireplaces. Though a fireplace and a mantle certainly add a bit of charm to any living room, they are also one of the most inefficient heating solutions for a home. Cast iron wood stoves might conjure up images of an old log cabin in the woods used to cook meals while simultaneously warming the house. However, modern-day wood stoves have become impressively efficient. As a result, they can be used as a sustainable heat source for homes, even in the coldest climates. Below, Rise takes a look at how modern and efficient wood stoves might be able to help you save money on your heating bills this winter and for years to come.
According to one leading energy company, the average home located in an area with a mild climate in the United States will use somewhere between 5,000 kWh and 30,000 kWh of energy a year for its heating needs. Homes located in areas with colder climates will certainly use much more. The Energy Information Administration (EIA) estimates over half of residential energy use (51 percent) is dedicated to heating and air conditioning in the home. In terms of household carbon footprint, every kWh of electricity used roughly amounts to one pound of carbon dioxide released into the atmosphere.
For households that use natural gas for their heating needs, every million BTUs of heat releases an average of 117 pounds of carbon dioxide into the atmosphere. So considering that the average US household uses around 77 million British thermal units (BTUs), your comfy home interior during those cold winter months is probably releasing over 9,000 pounds of CO2 into the atmosphere.
Might there be a way to sustainably heat your home without contributing a massive amount of emissions that are driving global climate change? If you have the budget, installing an air source heat pump powered by a rooftop solar power system is a great way to heat your home with renewable energy. Heat pumps have come a long way and can now be efficient in cold climates, working well below zero.
Burning wood for heat and energy has been a practice of our human ancestors for millions of years. Unlike coal, heating oil, natural gas, and other commonly burned fuels for home heating, wood is a renewable resource. Wood fuel is widely considered to be a carbon-neutral heating source. As the trees grow in their natural ecosystems, they capture carbon from the atmosphere and store it in their biomass. This carbon is subsequently re-released when firewood burns inside efficient wood stoves.
Of course, clear-cutting an old-growth Redwood forest to supply thousands of homes with wood for heating is undoubtedly NOT a sustainable practice. However, homeowners with even a small bit of yard space could consider planting various fast-growing trees. In a few years, these trees might provide their home with a sustainable and autonomous fuel source.
Speaking from experience, about four years ago, I planted sixty alder trees in a tree line at the edge of my small farm. This past month, we "harvested" 5 cords of alder firewood that will be more than enough to heat our home throughout the winter sustainably. Not only is alder an extremely fast-growing tree that also supplies nitrogen to the soil, but it also is a great "crop" for coppice farming. The trees that we cut down last month are already beginning to re-sprout from their stumps, thus promising a future harvest of firewood in 3-4 years.
Modern and efficient wood stoves, then, can sustainably heat a home while drastically limiting carbon emissions. For homeowners with a small yard, you might even be able to plant an independent fuel source for your home. What about the other pros and cons of this alternative heat source?
The smoke and soot from wood-burning stoves can be a significant source of air pollution. In densely populated areas, tens of thousands of wood-burning stoves might negatively impact public health by filling contaminated urban air with even more particulate matter. However, modern, efficient wood stoves certified by the EPA drastically reduce the amount of wood that needs to be burned. As a result, these stoves generate less air pollution and wood ash. In addition, the best wood stoves will be able to convert about 83 percent of the heat from the wood into usable heat for your home. Rocket mass heaters might even go further. Their efficient design means that only water vapor escapes from the chimney instead of contaminating wood smoke. In addition, many wood stoves come with catalytic converters and air filters that reduce the amount of smoke released through the chimney.
If the smoke from a wood stove enters your home, several contaminants will worsen your indoor air quality. These include particulate matter, carbon monoxide (CO), VOCs, and polycyclic aromatic hydrocarbons (PAHs). To keep the air inside your home healthy, be sure your wood stove is installed correctly, maintained and that your chimney is cleaned annually. Also, when purchasing new, check that the stove is approved by the EPA. Stoves with this designation will be efficient and burn cleaner, both inside and outside the home.
Be sure to have smoke and carbon monoxide detectors near your wood stove to warn you if anything is amiss.
Another potential drawback to wood stoves is their potential contribution to deforestation. If you can't grow your trees for fuel, pellet stoves (which we will review below) rely on byproducts such as sawdust from the timber and lumber industries.
A fire in an open hearth might bring a bit of holiday charm to your home. Unfortunately, this type of standard fireplace is only 10 percent efficient at best, as 90 percent of the heat escapes out the chimney. Modern-day efficient wood-burning stoves can achieve efficiency ratings up to 85 percent.
When combined with thermal mass, such as a stone hearth, the heat generated by the fire will be soaked up by the mass and slowly released into your home for long-term, sustainable heating.
Also, EPA-certified wood stoves are guaranteed to be at least 50 percent more efficient than other market options.
Modern-day, high-efficiency wood stoves use several innovative techniques to increase the efficiency of wood combustion. The firebox is frequently insulated, and a large baffle is designed to create a more extended and hotter flow path for the fuel. A baffle plate in the stove can help maintain the heated air and waste gases inside the firebox for more extended periods. This baffle produces even more heat from burning wood. Some efficient wood stoves will even send pre-heated combustion air into the firebox through small holes above the fuel in the firebox.
The most efficient wood stoves on the market will likely have a catalytic converter. During catalytic combustion, the smoke from a fire passes through a coated ceramic honeycomb. This addition reignites the smoke gases and particles, thus reducing air contaminants from the chimney while producing a long, even heat output.
The answer to this question will ultimately depend on your home's size, the quality of your insulation, and how sealed your building envelope is. However, for passive houses or other energy-efficient building techniques, a high-efficiency wood stove should offer more than enough heat for your entire family.
However, it is essential to note that for Passive Houses and houses with very tight building envelopes, installing an efficient unit with an air inlet directly from the outside is necessary. This inlet enables the fire to burn in ideal conditions, and the stove won't be stealing oxygen from your space. Some manufacturers, like MCZ Group, have designed new, completely sealed options, specifically for energy-efficient and Passive Houses.
Properly sizing the right wood stove for your home is another crucial step to ensure that your wood stove provides enough heat for your whole residence. Check out this database of EPA wood-burning stoves to search for the best option for your home.
There are dozens of high-efficiency wood stove manufacturers on the market. Two of the most efficient options are:
This Drolet Wood Stove is an excellent option for larger homes that require a significant amount of heat. The stove can produce upwards of 49,500 BTU while still maintaining a low emissions rate of 1.32 grams per hour. In addition, the stove has a maximum burn time of 10 hours, allowing you to keep your home warmed during those long winter cold spells. The unit also has a 71 percent efficiency rating.
This Englander Stove, an EPA-certified product conveniently sold at Home Depot, is another good option for large homes. It is designed to heat up to 2,000 square feet and includes a large firebox and blower to increase the unit's efficiency.
Homeowners looking to incorporate a sustainable wood-burning stove into their homes will need to decide on the best fuel type. If you don't like the idea of chopping logs or stacking firewood, pellet stoves might be a good option. The US Department of Energy states that "pellet fuel appliances are more convenient to operate than ordinary wood stoves or fireplaces, and some have much higher combustion and heating efficiencies."
The pellets, conveniently sold in bags that you can purchase from your local hardware store, are essentially nothing more than compressed biomass. They are usually sourced from waste products such as food waste, agricultural residues, energy crops, sawdust, and wood chips. However, heating your home with wood pellets can lead to a higher cost, especially if your wood stove is your primary heating source.
A pellet-burning stove will generally require about 40-pounds of wood pellets per 24 hours of heating. With the average 40-pound bag of pellets costing $5, a home with 120 heating days, then you could expect to pay around $600 for wood pellets. A similar wood-burning stove might require 3-4 cords of wood for a winter heating season. If a cord of wood costs $120 in your region, the cost of wood fuel will most likely be significantly less.
Whether you choose a wood stove or a pellet stove, make sure to look for EPA certification and some of the other high-efficiency features mentioned above.
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.