Pool solar battery?

[solarpooldiy]

Hi folks. I recently repaired my 18x36 in-ground pool, and to extend the season, installed an electric heat pump pool heater. I had already had power at the pool (240v, 20 amp service), and hadn't considered the cost of running additional power for the heat pump when I ordered it a few months ago. The pump needs 40 amps at 240v, so for wiring, it needs a 50 amp breaker in my panel at home, and a new run of 60 amp wire to the pool. I don't have 50 amps of breakers available in my panel, so I need a new subpanel at home. I also need a run of 100 feet with 60 amp wire, put in a Schedule 40 PVC pipe, 2 feet down, in a trench run from my house to the pool. I'd probably also (for safety), need an outdoor subpanel (or at least a breaker) at the pool so I can shut off the power quickly in case of an emergency.

So, for those keeping score at home, I need:
1 home subpanel
1 100 foot run of 60 amp wire, in a PVC pipe, in a 2 foot deep trench
1 weatherproof outdoor subpanel

In talking about getting this work done with a couple experienced electricians in the area, it's looking like it'll cost between 5k and 10k to do this work. This is a one time cost, and then I have to pay for the electricity....

That got me thinking - am I better off buying some solar panels, and either ground or pole-mounting them, and wiring them to a 240v battery solution to run the heat pump? Or maybe I don't need a battery, and just need a controller that can output 240v? I was thinking the battery could regulate the incoming solar power to put out a steady supply to the heat pump, whenever it can...

I won't need much in the way of electrical storage capacity, just a place to land the power from the solar array. I can install the battery right next to the heat pump and save myself the long run of 60 amp wire. I figure if I can spend 10k on solar, I can at least recoup some of those costs by running the heat pump (and maybe the pool pump) off solar...

I don't need to run the heat pump 24x7 - if it runs as long as we have sun, that's fine. The goal is to heat the pool a bit more so we can start the pool season earlier (May?) and end the season later (October?).

Is this too crazy an idea to consider? Or might it work?

 

[hwy17]

Pool heat pumps are energy monsters. You could post the specific model for more details.

I would imagine you're looking at like $3500 inverter, $2700 battery, $6000 panels, and idk $2000 in racking, and that's all DIY with another $1000 in wire and incidentals.... plus trenching.

 

[740GLE]

Also if your main goal is to extend the season of the pool spring and fall, to me that means loosing out on peak solar months of the summer (assuming you’re further away from the equator) So again another strike needing substantial amount of PV panels.

What’s the BTU of the heat pump? Inverter style? Chances are it won’t run 100% all the time if you’re just trying to get another month or so out of pool use, so you might be able to get away with a 5000w inverter.

 

[solarpooldiy]

Also if your main goal is to extend the season of the pool spring and fall, to me that means loosing out on peak solar months of the summer (assuming you’re further away from the equator) So again another strike needing substantial amount of PV panels.

What’s the BTU of the heat pump? Inverter style? Chances are it won’t run 100% all the time if you’re just trying to get another month or so out of pool use, so you might be able to get away with a 5000w inverter.

This is the heat pump site: https://aquacomfort.com/heat-pumps/xl-series/ - I have the ACT1500, which is the 130,000 BTU model.

 

[timselectric]

Here's what I would do. Assuming that you have a covered area near the pool. (Or can build something)
Feed your existing 20a circuit into 2 or 3 Growatt SPF-5000-ES. With 5 or 10 kwh worth a battery.
This would give you the intermittent higher power needed. With a constant charge to the battery.
And you can add solar to save money as funds become available.
Could be done for around $7k , not counting solar.

 

[timselectric]

Here's what I would do. Assuming that you have a covered area near the pool. (Or can build something)
Feed your existing 20a circuit into 2 or 3 Growatt SPF-5000-ES. With 5 or 10 kwh worth a battery.
This would give you the intermittent higher power needed. With a constant charge to the battery.
And you can add solar to save money as funds become available.
Could be done for around $7k , not counting solar.

Actually, it would work better to feed the existing 20a circuit into a chargeverter.

 

[justinm001]

I'm about to install a pool heater too but mine requires 100amps (cheaper Chinese heater).

If you have the room too install solar by the pool it's much more efficient to run solar pool heaters which move water through to heat it directly by the sun, just needing a small pump to push the water through. I can't do this and risk the water leaking as it's a vacation home.

Solar would take a ton and another conversion entirely.

It makes the most sense to just have a line ran, I'd even get a larger wire so you don't need to worry about it down the line. 100a would be best so everything runs off the new panel and use the old as an extra. Wonder if it'll be cheaper to have electric company run a new meter just for pool?

If youre set on batteries then run the 240v 20a power that you have now into an inverter to charge batteries then drain the power when running the heater. Also get a variable speed pump if not already then you can lower the wattage to help charge. Also depending on the heater can lower the wattage when heating. I think Victron is the only inverter with powerassist so you could get a pair of them in parallel then use the 20a plus inverter power

 

[solarpooldiy]

I'm about to install a pool heater too but mine requires 100amps (cheaper Chinese heater).

If you have the room too install solar by the pool it's much more efficient to run solar pool heaters which move water through to heat it directly by the sun, just needing a small pump to push the water through. I can't do this and risk the water leaking as it's a vacation home.

Solar would take a ton and another conversion entirely.

It makes the most sense to just have a line ran, I'd even get a larger wire so you don't need to worry about it down the line. 100a would be best so everything runs off the new panel and use the old as an extra. Wonder if it'll be cheaper to have electric company run a new meter just for pool?

If youre set on batteries then run the 240v 20a power that you have now into an inverter to charge batteries then drain the power when running the heater. Also get a variable speed pump if not already then you can lower the wattage to help charge. Also depending on the heater can lower the wattage when heating. I think Victron is the only inverter with powerassist so you could get a pair of them in parallel then use the 20a plus inverter power

The new meter idea is interesting.

For equipment, I already have a 240v variable speed pump. I also already have the heat pump installed (specs above) - just not connected yet. The solar roof heat may be a next-summer project to augment the heat pump. In our area outside of Boston, when it gets colder (like this week), it tends to also be cloudy, and in the 70s, so solar thermal pool heating alone is unlikely to generate enough heat gain to be worth it when I need it most.