Heating with All-Electric Hot-Water Baseboards
Randy_Burgess
| Posted in Mechanicals on
Hello, I am helping my parents electrify their house and they currently heat solely with hot water baseboards heated with an oil burning furnace. They are looking to install solar and want to stop burning fossil fuels, and have heard about Heat Pumps for water heating. Do these reach temperatures high enough to provide heat for a house in Maine? The bones of their house wouldn’t allow for ductwork, so they probably will be keeping the baseboard system. If the heat pump alone isn’t enough, are there systems which allow for a combination of heat pump and electric resistance to reach high temperatures for heating?
Thanks,
Randy
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Replies
Regular heat pump water heaters won't work to heat a house. There may be air source heat pumps intended for hydronic heating systems, but I'm not aware of any.
If your goal of electrification is to reduce emmissions, don't use electric resistance heat. Using electric resistance heat will result in MORE emissions for the same amount of heat due to the inefficiencies of the electric generation and transmission systems. The only way electrification reduces emissions is to use heat pumps that move energy, so you can get more BTUs of heating performance per unit input energy than you can with electric resistance which is always a 1:1 ratio of input to output energy.
It's highly unlikely you'll be able to heat your home entirely with solar power, especially someplace like Maine. You can certainly use solar to "help out" though.
BTW, the usual way to convert a house like this to all electric is to use a multisplit system. That may be something you want to consider, and remember that it has the added benefit of getting you air conditioning at the same time.
Bill
You could use a to-water heat pump. Ductless mini-splits are cheaper and easier.
Minisplits are the most common option here, but how well they work depends on the insulation etc of the building - I wouldn't want to try to heat a leaky old house with minisplits, that can end up being a lot of capacity to install, even with elec backup for peak needs.
Air-to-water heat pumps are here, but few are installed so far. I'm hoping that in the next few years we see more of them, especially as drop-in replacements for houses like this with existing hydronic heating. Spacepak has a couple models, Aermec, Nordic, and Chiltrix are others. But like I said, it's still pretty a new market here - but one I hope we see a lot more of very soon.