Most homes in Britain currently run on either an oil or a gas boiler, but that’s about to change. Starting in 2025, new homes will need to be built with alternative heating systems. The shift away from the traditional boiler is part of the British government’s bid to reach net zero emissions by 2050.
That shift, as well as debates around ending the use of fossil fuels to heat homes altogether, are likewise cropping up in various U.S. states as different levels of government work to decarbonize.
Although furnaces have become by far the more popular choice in North American homes, it’s not uncommon to find a home in the northeastern U.S., or a commercial property, that uses a gas boiler. Those boilers are likely to become harder and harder to replace as cities and states phase them out.
Heating buildings is a significant end use of fossil fuel energy on both sides of the Atlantic. Decarbonizing space heating, then, could be a significant step towards reducing emissions in any country. If you find yourself in the position of wanting to (or being compelled to) find an alternative for your gas boiler, explore these greener options to see if one might be the right fit for your home.
Air Source Heat Pumps
Air source heat pumps extract heat from the outside air and pump it indoors in order to heat the home. It seems counterintuitive to think that this would work in winter. Natural Resources Canada explains, however, that “even when outdoor temperatures are cold, a good deal of energy is still available that can be extracted and delivered to the building. For example, the heat content of air at -18°C equates to 85% of the heat contained at 21°C.”
There are a few different kinds of air source heat pumps. Air to air pumps use fans to blow heated air through vents. Air to water pumps, on the other hand, distribute heat through radiators or underfloor heating. These systems have the advantage of working both as a heater and an air conditioner. They’re also cost-effective—they tend to be low maintenance and long-lasting, and their efficiency makes them very cheap to run.
They do require electricity, however. This could impact your monthly costs positively or negatively, depending on the price of electricity in your area and what you’ve been paying for fuel.
Biomass Boilers
Biomass is plant-based material, often wood pellets or chips. Heating with biomass simply means burning that material for heat. Both hydronic and forced air systems can be fueled by biomass. It works on the same principles as a gas boiler or furnace, just with a different fuel.
This kind of heating system needs regular cleaning, as well as fuel supply management. You’ll also need a place to store fuel. Cost-wise, they’re more expensive than other types of boilers, although biomass is cheaper to run than electric heating.
While these systems are efficient, they do produce emissions. On the whole they’re considered environmentally friendly, however, because they use renewable fuel sources; often even using waste from the lumber and agricultural industries.
Electric Boilers
One option is to simply replace a gas boiler with an electric one. They work just the same as gas boilers do, and use the same systems of pipes and radiators. This means few changes to existing heating systems, which could be a big bonus. Electric boilers are cleaner and safer to run than gas boilers. They’re also more energy efficient.
That said, they do tend to be less powerful, and are therefore more effective for smaller homes. The cost of purchasing an electric boiler will be higher than purchasing a gas one. Also, an electric boiler will be more expensive to operate if your electricity rates are higher than the price of gas, which is typically the case.
Ground Source Heat Pumps
Ground source, or geothermal, heat pumps work much the same as air source heat pumps, except that they move heat up from below ground, where temperatures in winter are warmer and more stable than the surrounding air. The most common types are horizontal and vertical closed loop systems.
In a horizontal loop system, pipes are buried in trenches 4-6 feet deep. Vertical systems bury pipes to a depth of up to 400 feet. In both cases, the pipes contain a refrigerant that circles through them. The fluid picks up heat from the earth, passes through a heat exchanger and then returns back to the earth.
There are many pros to ground source heat pumps. They can function as both heating units and air conditioners, aren’t subject to temperature fluctuations, are extremely efficient, low-maintenance and long-lasting. The cons include considerable installation costs and some tricky logistics for some homeowners who might not have space to bury pipes.
Infrared Heating Panels
This option sounds a bit sci-fi, but it’s a real thing that works by turning propane, natural gas or electricity into infrared heat. These systems work by heating surfaces like floors, furniture and bodies (much like sunlight does) instead of heating the air. They’re often installed on the ceiling so they can heat floors, which will then radiate heat upwards.
Infrared panels are quiet, efficient, don’t use ducts, fans or other common HVAC system components, and provide instant heat. They’re cheap to purchase, although they could be expensive to run, depending on your electricity rates.
There are other cons to consider here, too. Since the heat is directed, areas outside the reach of the panel will stay cold. Although they’re considered safe, there could be concerns with skin issues and light emissions that you should investigate if you’re interested.
Solar Thermal Systems
Solar thermal heating systems use a solar collector to heat a transfer fluid. The fluid is pumped through pipes and passed through a heat exchanger, which extracts the heat from the fluid to heat the home. The system is automated such that it switches the pump system on when it senses that the temperature in the home’s hot water tank has fallen to a specific temperature below the temperature where the collectors are.
The big down side to solar thermal systems is their variability. Solar collectors work fine even when it’s cloudy, so they will function in the winter. Depending on your local weather and your heating needs, however, you’re likely to need a back-up to keep your home comfortable.
They can make a sizeable dent in your monthly energy bills, however, and often come with government grants to help defray the costs of installation.
Feature image: Alex Perz; Image 1: Erik Odiin
