Please help us with a tough decision!!!

[mihzyd777]

Ok here's getting to the point. 3 years ago we put 7 pool solar heating panels on the roof. 5 of the panels are on the south facing roof with the other 2 on the West facing roof. I have a large roof (2000 sq. ft.) home but just way to many different roof lines, so my options are limited here.

We have decided that it's more important to put Solar Electricity up. However we still need to keep our pool warm. A heat pump from what I'm told is out of the question, since I have a 125amp main breaker panel and as per my city's code in California, I can upgrade it to a 200amp panel due to having only 2.5" conduit coming up from the ground from PG&E vs. 3" conduit. We recently purchased a Electric vehicle and had to add a 30amp breaker for that. The solar we will be putting up requires a 50 amp breaker which we will put in a subpanel to get this done and change out the 125amp breaker to a 100amp breaker which as per city inspector is fine. So that means I really don't have room for a heat pump.

So here is my ONLY option:
- Move 2 out of the 5 on the south facing roof to the East facing roof directly opposite of the other 2 panels on the West roof. The remaining 3 will be brought down and stored away as I don't have enough roof to mount them.

So let me ask anyone who has experience with these solar pool heating panels, Obviously going from 7 panels down to 4 panels will reduce efficiency and how fast the pool heats up etc... I know I'll have to run the pump long, but at a slightly lower speed due to only 4 panels being up on the roof. The company that installed the panels wants to charge me $400 to move the 2 to the East Roof and remove the other 3 completely. Is this a good price? I have to go with them and can't do it myself due to being under warranty for 9 more years.

So what to do? I guess I don't really have a option because if you agree that solar electric is more important then there really isn't a issue.

So the real question I guess is will I still be able to heat up my 18,000 gallon pool somewhat ok in the summer? The panels I have a 4' x 12' Fafco panels.

Thanks!

 

[jblizzle]

Does not sound like you really actually have a decision to make.
You are adding solar power so you must move the pool solar.
You are under warranty so must pay to have the pool solar moved.

The 4 panels and non-optimal orientation are likely to cut the available heating by at least 50% from what you had before. So don't have higher expectations.
If you are running all the water through the panels, then you might need to lower the speed, but that does not likely mean you need to increase the run time.

 

[Isaac-1]

I have to question if this is right move, thermal solar is far more efficient in BTU per area than photovoltaic solar, so you may be trading off ability to heat your pool for the ability to generate electricity.

 

[mihzyd777]

Even though I would be zeroing out my electric bill and breaking even in 5 years?

 

[ping]

It sounds like you really don't have a decision to make as Jblizzle said. Your plan is thought out and you will have both solar for the pool and electrical for the house installed where they will be most optimal for your roof.

The performance for the pool will take a large hit from what it is now, but if you are not using a cover, adding one will help and you should still be able to raise the temp to your liking.

 

[JohnT]

Even though I would be zeroing out my electric bill and breaking even in 5 years?

I think the answer was assuming (because I assumed it myself when I read your post the first time) you were going to use the electricity from the panels to run a pool heater. That would be less efficient than just heating the water directly with solar.

Just throwing a thought out that you might be able to construct a pergola or cabana that doubles as a solar panel rack for the pool panels so you wouldn't have to give them up.

 

[Pool Clown]

How much property do you have? Solar panels don't have ​to be on the roof.

 

[gwegan]

Will you actually be giving up that much? You don't say where you live in California. In the middle of the summer (now) my solar only runs 1/2 the time it is allocated before it shouts off because it has reached its target 91 degrees. Are you having to run the solar all day to reach your target? Also adding a solar cover at night really helps retain heat. I would expect the big loss would be in April, May and October.

 

[dumbcluck]

this may be a different point but you are never going to be able to zero out your electric bill. I hope the solar installers have made you aware of this. it doesn't matter how many panels you put up in fact the "extra" will just go back into the grid. consider it a donation on your part. energy companies are not in the habit of writing checks. many people don't realize this. just for the record, you will also still be without power in a blackout or power outage unless you have battery back up system or generator.

 

[JohnT]

this may be a different point but you are never going to be able to zero out your electric bill. I hope the solar installers have made you aware of this. it doesn't matter how many panels you put up in fact the "extra" will just go back into the grid. consider it a donation on your part. energy companies are not in the habit of writing checks. many people don't realize this. just for the record, you will also still be without power in a blackout or power outage unless you have battery back up system or generator.

Many states, including California, require utilities to pay for excess power from home generating systems.

 

[aussieta]

in Australia you can get photvoltaic solar panels with a water heat exchanger mounted to their underside
the water keeps the panel cool which improves its performance and only takes up the roof space of one set of panels
http://reneweconomy.com.au/2013/pow...rid-solar-panels-approved-for-australia-25985

 

[dumbcluck]

I stand corrected john t. I just looked it up and they are in fact now honoring such credits. my apologies. this was not the case years ago when I was doing photo voltaic installations. this is good news indeed. never mind what I said.

 

[greg.stevenson.90]

From an electrical stand point. Is the solar electric panels drawing power? No. That 50 amp breaker is protecting the wire bringing power into your panel. No? So really that 50 amp breaker shouldn't be considered in your panel as any other breaker using power.... No?
As long as the heat pump isn't running while using another large load in your house, I bet you would have no problem.
The 2.5" pipe coming up out of the ground, is it piped a long way? In many areas its simply a sleeve that goes down about 2-3' then it's buried wire. Easy to change to 3". That's not to say I'm wrong on any of this, but s

 

[dtlight]

From an electrical stand point. Is the solar electric panels drawing power? No. That 50 amp breaker is protecting the wire bringing power into your panel. No? So really that 50 amp breaker shouldn't be considered in your panel as any other breaker using power.... No?
As long as the heat pump isn't running while using another large load in your house, I bet you would have no problem.
The 2.5" pipe coming up out of the ground, is it piped a long way? In many areas its simply a sleeve that goes down about 2-3' then it's buried wire. Easy to change to 3". That's not to say I'm wrong on any of this, but s

His problem would be passing an electrical inspection. The NEC is quite specific about back feeding solar into an existing panel bus bar. You cannot exceed the bus bar rating by more than 25%, and then only in specific circumstances. The original poster could install a 200 amp panel with a 125 amp main breaker and be compliant, but if they can live with the 100 amp main breaker in their existing panel that will be a lot cheaper.