New pool + solar panels on roof. Best heating choice?

petepool

Member
Sep 1, 2019
24
North NJ
I've purchased a house where I will be concurrently installing solar on roof and building a pool in backyard. The solar decision makes sense independent of the pool, but I am debating how much larger I size the system to take into account energy needs of pool pump (variable speed) and if I should go heat pump instead of NG.

House is located in north NJ, pool on south side of house, sun all day (no shade). 20x40 vinyl, 3-6' deep, no spa. Willing to do at least a solar cover, or maybe even an automatic cover to avoid the daily hassle of taking on/off.

Would use the pool only during the summer (memorial day to labor day), but would be used by kids all week not just on weekends. Want it to maintain temp (mid 80s) even if we get a few cold nights in a row.

Upfront cost of NG vs. heat pump is the same, taking into account the cost difference of running gas line vs. electric.

Given the facts above what is optimal choice of heating in my situation?
 

PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
3,800
Damascus, MD
During the season your pool pretty much will maintain mid to low 80s on its own. Higher if you are religious about putting on the solar cover when the pool is not in use. If you want to utilize your solar panels then your only choice is a heat pump. I would add as many panels as your roof can hold. Cover as much area as possible. Heat pumps can easily maintain 90 degrees all summer without breaking the bank on power demands.
 

petepool

Member
Sep 1, 2019
24
North NJ
Thanks for that info - i didn't realize a pool would maintain 80+ by itself. There seems to be a wide range of views on heat pumps. Some people say they suck at getting water up to temp, while you are saying it easily maintain 90+ in the summer. Maybe its just matter of having the right heat pump...
 

PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
3,800
Damascus, MD
Thanks for that info - i didn't realize a pool would maintain 80+ by itself. There seems to be a wide range of views on heat pumps. Some people say they suck at getting water up to temp, while you are saying it easily maintain 90+ in the summer. Maybe its just matter of having the right heat pump...
Your pool for the most part will maintain the average ambient temperature without a heater. Heat pumps will heat the water slower - 2/3 degrees per day. Gas will give you 1-2 degrees/hour. Heat pumps efficiency is also tied to relative humidity and temperature. Get the largest heat pump you can find typically this is around 140k btus.

The best heater as far as heating ability is a gas heater. They will bring up your temp quickly. But they cost a considerable amount to run. My 400k btu is @ $5/hour to run. It provides 1-2 degrees per hour. I keep my pool off most of the week and turn the heater a few hours before we swim. Right now my pool is hovering around 80 since the nights are getting cool. If I turn it on in the morning by lunch it will be almost 90.
 

jimmythegreek

TFP Expert
Bronze Supporter
In The Industry
Aug 10, 2017
1,341
Morris Cnty NJ
I'm in NJ too and during summer pool is low 80s on average usually 81-82 if uncovered. One cold day drops temp. Covering pool makes a huge difference. My kids and wife want 90 degree water. I added solar this year and with a cover made temp easily. Kept upper 80s without a cover. If your solar panels can pay for the heat pump use it's a no brainer. Gas is great I have one too but use it for early and late season and point of use. We plan our swims on the edges of the season during summer its warm enough to just swim whenever. But this past weeks weather has the water at 73 today and all week. I have solar off and cover off over a week now. If we wanted to swim we would need the heater for 6 hours or so