Solar Assisted Heat Pump water heater – input needed
smgb
| Posted in Energy Efficiency and Durability on
There aren’t ideal areas on my house to mount solar heated hot water panels, so I looked into Solar Assisted Heat Pump water heaters and got a quote for this one
What are peoples’ experiences with these versus a traditional heat pump water heater that sucks heat out of the air in a basement?
I am located near Boston MA.
Thank you.
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The reason solar hot water never really caught on is that there's no practical way to make it provide heat when you need it, both on a daily basis and on a seasonal basis. A system that is right-sized in the summer provides only a small fraction of what you need in the winter; a system that is right-sized in the winter will have to have some way of shedding heat in the summer.
If you take the same roof space -- and less money -- and install solar EV panels instead you will capture about the same amount of energy. However, it will be in the form of electricity which you can use for any purpose. Since you're in Massachusetts you're eligible for net metering, which means you can bank any electricity you can't use at the moment for future use.
I had PV panels installed about 7-8 years ago
How much do they run?
About $4800 after incentives. This is for the solar assisted heat pump water heater.
Wow! That buys a lot of Solar PV
I spoke to the supplier on the US side for these some time ago. It can achieve COP of 3.0 in sunny conditions. If you use a decent amount of hot water while it's not sunny (evenings, early mornings) you end up using the resistance heater a lot, so that COP drops off quite a bit. Use the roof space to add a 450watt panel and you'll be better off was my conclusion.
I concur with Tim_O. Everyone is installing hybrid hot water heater which are much cheaper and there are many more installers and servicers of those units. Keep it simple.
Can you or Tim provide the specific name of the hybrid models you’re referring to? I’m new to all this so want to be sure I’m asking for it using the correct name / jargon. What’s a “hybrid“ hot water heater?
Hybrids are the heat pump water heaters you were thinking of in your initial post that use heat from your basement. That's really all there is out there for heat pump water heaters. SANCO2 is the only split system heat pump water heater.
They are called "hybrid" because they are a hybrid between a small heat pump and an electric coil.
The SAHP is a split system heat pump, is it not? The exterior panel is a fan-less evaporator panel, and there are refrigerant lines between the exterior panel and the interior compressor/condenser unit. Sure, it's also a hybrid with the aux electric element.
Nyle makes a split system heat pump as well. Same concept as the SANCO2 of a separated tank unit and condenser/compressor/evaporator unit (with water connecting the two units), but the Nyle condenser unit stays indoors instead of outdoors.
Yes, you are correct, SAHP is a split system.
I just saw some articles that Bosch released a new monobloc heat pump water heater and Samsung did as well. Unfortunately, must be European only. Eventually it would be nice to see them make their way over.
This is the one I have in my house:
https://www.supplyhouse.com/AO-Smith-HPTU-66N-66-Gallon-Voltex-Residential-Hybrid-Electric-Heat-Pump-Water-Heater
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