Heating Our Spaces and Not the Planet
When looking to increase the efficiency and sustainability of heating your home or business while reducing your carbon footprint and other pollutants, the best answers can be somewhat complex and vary depending on a number of factors. Clearly, the more tightly your space is insulated while, simultaneously, more efficiently ventilated (ie. higher performance), the better. This is why we wear warmer clothes in the winter, with, perhaps underclothing that ‘breathes’ and wicks away moisture, for maximum comfort using only our body’s own system of regulating its heat.
But the energy we put into heating our interior spaces, and how it is generated is still a big factor in the efficiency, cleanliness, effectiveness, and sustainability of our heating system. And each of these methods has its pros and cons. So, lets rule out a few approaches that just won’t fly going forward, if we wish to save energy, live in a cleaner world, and help mitigate the worst effects of climate change.
Burning Fuels for Heat is No Longer the Answer
Regardless of the technical efficiency of any fossil fuel solution such as natural gas, using it is not at all sustainable. Oil and natural gas furnaces use resources that are tremendously harmful to extract, aren’t renewable and will, eventually, become scarce, and, of course, continue to add to the carbon in the air. Even wood pellet stoves are a solution that would, eventually, deplete our resources faster than they could be renewed and, at best, can only get close to net zero, since we would burn the wood faster than we can grow it back.
Electricity is the Way Forward
So, basically, only an all electric approach qualifies as a viable solution to achieve all our goals in this regard. Please, keep in mind that, while we certainly still generate a great deal of our electricity with fossil fuels, the all-electric home instantly becomes cleaner as cleaner electricity comes on line. So this issue is really about how we make electricity and not at all about how we use it.
Ducted and Hydronic Centralized System Have Built-in Inefficiencies
At this point, it is important to mention that, no matter how the heat is generated or moved into the home or business, centralized, ducted systems and hydronic boilers suffer from a number of inefficiencies such as heat loss in the ducts or piping especially in unconditioned spaces (such as crawlspaces) as well as wasting heat in unoccupied spaces. Imagine if your home’s lighting system operated where, regardless of the room you were using, all the light switches turned all of the lights on or off in the entire home or, perhaps, floor by floor zone. When put that way, centralized systems can easily been seen to be flawed in this respect. Additionally, ducting and plumbing are expensive to install throughout the building, and can suffer from leakage – which, in the case of hydronic systems, can be disastrous.
Forced air systems also suffer from the inefficiency of needing to power a fan motor to blow air into the space and, in the case of hot air, the fact that hot air rises into the unused empty space above the occupants’ heads. Even mini-split ductless heat pumps suffer from this fact, even more so when the heat needs to move to rooms too far away from the internal cassettes or heads, making them cold spots. The solution using only this system would be to install more heads or involve ducting.
Ductless Heat Pumps are the Most Efficient but not the (Whole) Answer
Geothermal heat pumps are the most efficient way to both heat and cool interior spaces by making use of the constant temperature found underground year round that can be routed in or out of our interior spaces to keep them in a constant, comfortable range using very little electricity in almost any climate. However, the refrigerants used to capture and release the heat energy can be pollute the air and or ground in the case of leakage – which, at some point, is effectively inevitable if not caught and replaced in time. And, because pumps have moving parts, while they can be made durable, will eventually suffer from breakdowns, require maintenance in this regard, and at some point will wear out. Additionally, the well for the underground portion can be prohibitively expensive and, overall, mean these systems are not as sustainable, affordable, or clean as other systems I will mention going forward.
Air source heat pumps are next in efficiency and are much more affordable than geothermal systems. However, they also use refrigerants, have moving parts, and, when its below freezing outside, the condensation of water in the unit out in the frigid exterior air tends to freeze and must be defrosted (using additional power in the process while pausing interior heating), and even begin to fail to do the job if the temperature drops too low. When it is very hot and humid, they must work harder to evacuate the heat into the outside air. In both cases, the durability and efficiency of the system drops.
So, both types of heat pumps are, technically and in general, the most efficient methods of both heating and cooling. However, they are not maintenance free and eventually wear out. They currently house toxic refrigerants prone to leakage into the environment. And, since they have a somewhat complex structure of parts, they are not the easiest systems to repair, re-use or recycle (at end of usable life. Finally, because they must interact with the exterior of the space, penetrations in the building envelope are required which can compromise the performance of the insulating features that are so important to overall efficiency.
Electric Infrared Radiant Heat Solves Many Challenges Heat Pumps Do Not
Electric resistance heat turns electrical input into usable heat. The efficiency for a system that brings generated power into the home rather than moving heat energy in or out, as heat pumps do, can, at best, attain an efficiency approaching but not quite achieving 100%. Usually, the efficiency of any machine is based on how much energy is lost in the form of heat. For example, an LED light is so much more efficient (and durable) than an incandescent light because it converts most of the power into light and very little into heat. Those of us old enough to have changed an incandescent light too soon after it was turned off know just how hot a 100 watt lightbulb can get. However, when heat is what you are trying to produce, light not only may become undesirable (staying warm in a dark bedroom, for example), but can also be considered wasted energy. So, it you can see the glow of a heater, you are looking at wasted energy.
For many reasons previously stated, central, forced air, electric furnaces and hydronic boilers are probably the least desirable heating approach after burning fuel in terms of our desired goals. In-wall cadet heaters do have the advantage of room by room heating which, if used properly, can at least be controlled to put more or less heat into a space depending on where it is wanted or needed. But they are noisy, and waste energy with motors that blow rising air into a space. Baseboard heaters can be a bit more efficient, do not blow air, can be controlled room by room, and have no moving parts, but suffer from misdirecting the radiant h