Solar Water heater for ~$1500!

[nwdiver]

If you use hot water... you should really have one of these. Practically a drop-in replacement with the exception of the required condensate drain. And they're currently on sale for ~$1500. The sale usually lasts a month or so and occurs twice a year.

They use ~70% less energy than a traditional water heater.

 

[brkaus]

Solar?

 

[SageBrush]

Can it time shift heating ?
I would be most interested if I could use inside air for the heat source in the summer and outside air in the winter, although that is admittedly not so much an issue with the Rheem as it is with home design.

 

[nwdiver]

Solar?

~70% of the energy it uses is pulled from the air... which is heated by the sun. Solar.

'Heat Pump' seems to confuse some people. 'Solar' doesn't. The non-electrical energy is 70% of the energy and it comes from solar.

Can it time shift heating ?
I would be most interested if I could use inside air for the heat source in the summer and outside air in the winter, although that is admittedly not so much an issue with the Rheem as it is with home design.

It's WiFi connected; I believe you can schedule time shifting. It can also be ducted to pull and exhaust the air wherever is most convenient.

 

[SageBrush]

It's WiFi connected; I believe you can schedule time shifting.

With time shifting I imagine a COP closer to 4.5 since ambient air would be between ~ 50F to 80F, so perhaps 65F to 70F average.

Do you happen to know what refrigerant is used ?

 

[nwdiver]

With time shifting I imagine a COP closer to 4.5 since ambient air would be between ~ 50F to 80F, so perhaps 65F to 70F average.

Do you happen to know what refrigerant is used ?

R410A

 

[SageBrush]

R401A ozone depleting and GWP properties

I didn't ask what is in my Tesla, so perhaps I should not be too harsh with Rheem.

 

[nwdiver]

R401A ozone depleting and GWP properties

I didn't ask what is in my Tesla, so perhaps I should not be too harsh with Rheem.

Tesla still uses R134a. Last I heard there are flammability issues with the desired replacement R-1234yf.

R410A not 401. I didn't see 410 on the list but it is a potent GHG but not a threat to the ozone layer. The math works out though. For a typical family this will reduce energy consumption by >3000kWh/yr. Which on average is >3000lbs/yr of CO2. The full R410A charge in the HPWH is the GHG equivalent of ~2000lbs of CO2. And hopefully it won't leak refrigerant.

CO2 HPWH like Sanden would be better... but they're >$3k

 

[SabrToothSqrl]

I got one of these with 10% coupon and $400 PPL rebate.
https://www.lowes.com/pd/GE-GeoSpring-50-Gallon-Electric-Water-Heater-with-Hybrid-Heat-Pump/3664968

it's a little concerning that it's no longer sold..? But after initially having to have it fixed 3x in the first 2 months, it's been 100% fine ever since.

I have water come into the house, fill this heat pump only mode at 140 degrees, then it feeds into a 50 gallon propane heater at 120 degrees. The propane almost never runs, and I have 100 gallons of hot water on tap. (which yes, is needed). I wasn't going to just toss a working water heater by buying this. Also, I have it plumbed to run either water heater or series. I tried to run my house on just 50 gallon electric in hybrid mode and it couldn't come close to our water demands...

GE says its no longer being made. Guess next time I'll buy the extended warranty because no one makes anything more than 2 years now... at least then I'd get money back right?

I think it was like $1k, - $100 - $400 so like $500 all in, installed myself.

Next house I wanted to put this in the garage for free A/C for the garage... keep the humidity down too.

 

[mongo]

~70% of the energy it uses is pulled from the air... which is heated by the sun. Solar.

'Heat Pump' seems to confuse some people. 'Solar' doesn't. The non-electrical energy is 70% of the energy and it comes from solar.

Not in winter, then the energy comes from natural gas (my furnace) just like my current water heater.

 

[brkaus]

I'd love to get one. I have a tankless propane water heater feeding into a 12 gal electric heater on a recirc loop. I'd probably put this on the street side of the tankless, so the tankless would kick in if we ever ran out of hot water from this. I'd also turn off the electric elements and only use the heat pump.

It's all in the attic where there is plenty of heat available through the majority of the year.

Problem is I don' have 240v available at that location, so it's a bigger upgrade than I would like to take on.

 

[nwdiver]

Not in winter, then the energy comes from natural gas (my furnace) just like my current water heater.

Is your water heater in your garage? That's where it is usually is. Then the HPWH just scavenges heat that escapes from the furnace.

 

[AudubonB]

Not in winter, then the energy comes from natural gas (my furnace) just like my current water heater.

Why are you thinking heat pumps don’t work in winter? Still lots of calories to be gleaned.

 

[mongo]

Is your water heater in your garage? That's where it is usually is. Then the HPWH just scavenges heat that escapes from the furnace.

Heck no, I'm in Michigan , it's in my basement. For ya'll in warm places, it makes sense.

Why are you thinking heat pumps don’t work in winter? Still lots of calories to be gleaned.

I'm not saying it doesn't work. I'm saying it doesn't pull the energy from the sun when installed in my basement during fall/ spring/winter.

Edit: another advantage of EVs, no gas fumes for a garage combustion water heater to ignite...

 

[SabrToothSqrl]

the Geo one does not operate the heat pump below 40 I believe... but my basement has never gotten that cold either. My Sense records when it runs.

Stats
Estimated kWh/year
Based on last 30 days
~162 kWh
Average usage
168 w
Average times on/month
38x
Average run time
3h
Average cost/month
$2

 

[nwdiver]

Heck no, I'm in Michigan , it's in my basement. For ya'll in warm places, it makes sense.

That's even better! Seriously doubt your basement ever gets <0C

the Geo one does not operate the heat pump below 40 I believe... but my basement has never gotten that cold either. My Sense records when it runs.

How's your Geo running. Mine is a POS Wanna buy a Rheem but I think I'll try to keep my Geo working a little longer.

 

[mongo]

That's even better! Seriously doubt your basement ever gets <0C

Better not, that's conditioned space! If one is in a heating climate, why pay extra for a heat pump water heater to convert the heat energy from my furnace into heat for the water, while spending electricity to do it? For $500 more I can buy a 95+% high efficiency condensing water heater instead.

For low cost hot water, evacuated roof mounted panels combined with a storage tank and solar power drain back pump is an interesting option...

I am planning to get a Chiltrix system for our multipurpose outbuilding (radiant floor and domestic hot water)

 

[nwdiver]

Better not, that's conditioned space! If one is in a heating climate, why pay extra for a heat pump water heater to convert the heat energy from my furnace into heat for the water, while spending electricity to do it? For $500 more I can buy a 95+% high efficiency condensing water heater instead.

For low cost hot water, evacuated roof mounted panels combined with a storage tank and solar power drain back pump is an interesting option...

I am planning to get a Chiltrix system for our multipurpose outbuilding (radiant floor and domestic hot water)

Hmmm... most basements I've seen aren't part of the AC envelope of the home.

$/$ a HPWH has a much better ROI than evacuated tubes. For most areas they likely use about the same electricity too. A friend here in NM had an evacuated tube water heater installed ~10 years ago or ~$7k. She depends on resistance backup when there isn't enough sun and it uses a pump to circulate fluid so it likely only reduces the electric consumption vs a standard water heater by ~70%... roughly the same as a HPWH but >4x the cost.

The power-pipe is another option...

 

[mongo]

Hmmm... most basements I've seen aren't part of the AC envelope of the home.

$/$ a HPWH has a much better ROI than evacuated tubes. For most areas they likely use about the same electricity too. A friend here in NM had a evacuated tube water heater installed ~10 years ago or ~$7k. She depends in resistance backup when there isn't enough sun and it uses a pump to circulate fluid so it likely only reduces the electric consumption vs a standard water heater by ~70%... roughly the same as a HPWH but >4x the cost.

Interesting, around here houses have full basements and are usually finished. Given the frost line, there is little additional cost to go the extra 2 feet down to make a basement vs crawlspace.

Since this had me wondering, heat pump water heater is way better than straight electric, but how does it measure up when paired with a furnace?

At a COP of a bit over 3 in this area, the $/BTU is that same for electric vs natural gas. Standard gas water heater is ~65% efficient.
100,000 BTU at a 3.7:1 COP, is 27kBTU of electricity and 73kBTU of ambient heat. 73k ambient heat requires 91k natural gas @ 80%. Total energy of 118k BTU. Cost wise, 27k BTU of electricity is 8.6kWh at $0.11 or $0.95, Natural gas is around $1/100 kBTU so $0.84. Total cost $1.79.

If you have a 95% efficient furnace, then it would be 33kBTU electric, 77kBTU gas, $0.95 + 0.77 = $1.72.

Compare to 100kBTU at 65% (standard power vent gas water heater), total gas usage is 149kBTU or $1.49.
For completeness, the straight resistance heater would be $3.22 .

If one has an electric water heater, the heat pump type is definite winner. Depending on exact climate and utility prices, it can be break even or favorable vs a gas water heater(offsets AC in summer if in conditioned space).

 

[nwdiver]

If one has an electric water heater, the heat pump type is definite winner. Depending on exact climate and utility prices, it can be break even or favorable vs a gas water heater(offsets AC in summer if in conditioned space).

You would probably break even in the winter then make up for it in the summer.