We are experiencing both the pain of global climate change and increasing costs for energy. If you have a heating and cooling system over 10 years old, it may be time to consider a newer, more efficient unit. There are three types of systems that may be better for the environment, less expensive to use (in one case far less expensive to use), and potentially more reliable long-term.
The three types of systems are central heat pumps, mini splits (which are also generally heat pumps), and geo-thermal heating and cooling systems. Let’s look at the advantages and disadvantages of each.
Heat pumps
Heat pumps are currently the most popular way to both save energy and more efficiently use electricity to heat and cool your home or business. They work by using a compressible medium to move heat from one place to another. They have also become popular in electric cars for both heating and cooling the cabins and the battery packs which like the same temperatures we do for extended life and reliability. Their big advantage in terms of global warming is that they don’t use natural gas to heat and are entirely electrical.
Their downside is that they lose efficiency and may not work at all in extreme cold, but newer, premium units have the range to handle typical Central Oregon winters. They tend to be relatively simple and reliable as a result and come in two forms: central and mini-split.
You want to avoid the need for emergency heat which uses a very inefficient form of heating, which is why you need to make sure the unit you select will handle the typical cold of Central Oregon.
Mini-split vs. central
The central heat pump system’s advantage is that it is easy to retrofit and tends to be less complex than a mini-split. The disadvantage is that it tends to heat and cool the entire structure, even parts where there are no people, meaning you are paying to condition areas that aren’t in use. You can go with a zoned system, but your upper limit is typically four zones, and this option does increase the cost of the installation significantly. Emme makes a system that will handle more zones, but the only provider in Central Oregon that once carried it has stopped, which makes getting the unit serviced problematic (it is what I have in my home).
Mini-splits come in a variety of sizes, and you can have as many as you want in your home. Only using the units in the rooms or areas you are occupying can reduce your energy consumption significantly. These are best for new structures as retrofitting them can require opening ceilings and walls, increasing not only the installation cost but potentially damaging any unique wall or ceiling treatments you have.
My advice is, if you can, to go the mini-split route, but if you don’t want to risk the painful retrofit, then go with a central heat pump and zone the system.
Geothermal
Geothermal heating and cooling systems can save significantly over regular heat pumps. They circulate heat by exchanging liquid underground or in water and are far more efficient given ground temperatures are more stable than air temperatures and are more efficient at moving heat in and out of the building. I’ve only seen central units that are more expensive to install. These typically require you to dig up a large area or drill a deep hole (problematic if you, like me, are on volcanic rock) and are easier to do with new construction or where you have a large area that can be easily disturbed to bury the pipe. While they are potentially more reliable than your typical heat-pump, they tend to be built by off-brands and in smaller numbers, which means there isn’t a lot of information about their reliability or many installers who know how to make them work.
In my case, the bid just to dig the hole I needed for the pipe was $85K making it extremely prohibitive to use and I didn’t want to destroy my expensive yard landscaping to install the pipes horizontally. So, for me at least, this was too expensive of an option. But, if you can use it and you are a bit technical, this is an option and maybe a requirement for an off-grid home where extreme savings is more of a requirement than a nice-to-have option.
Wrapping up:
As we approach winter, you can save a lot of money and help the environment if you replace your aging and inefficient heating and cooling system with one that is far more efficient. Geo-thermal systems will provide the greatest savings but cost the most to put in, and their unique nature does introduce some risk to the approach if only by limiting your ability to choose between vendors (I only found one Central Oregon company that would do this, and they were not excited about the opportunity).
Mini-splits are your next best choice, but they can be ugly to retrofit, so they are usually preferred for new installations. Central heat pump solutions may be the easiest way to get something more efficient and likely cheaper to install for retrofit, but assure their operating range covers the likely range for temperatures in Central Oregon so they don’t have to use emergency heat which is expensive, wasteful, and goes against your desire to lower your energy cost and fight global climate change.
Be aware that most cooling systems, and these are no exception, tend to remove moisture from the air which can be helpful in humid climates but can be too dry in areas like ours where the air is already dry. You may want to consider a humidifier and well for comfort.
Good luck, and I hope you have a comfortable, relatively inexpensive green winter!
