Sunpower system in San Diego - Good deal?

[LukeD]

I am thinking the portion of credit taken in a tax year is limited to the TAX LIABILITY, but NOT to WITHHOLDING.
Otherwise withholding could just be adjusted up, getting a gigantic refund later.

Tax years to get back a state tax credit might exceed a lifetime. Bruce Roe

Not sure why anyone would want to increase their withholding. It's your money your just getting back anyways. But you're right, it could take my buddy years to get the total credit since he usually gets most of his withholding back anyways from his mortgage interest & property tax deductions. He probably only chips away about $1,000 to $2,000 per year. That'd be 7-15 years!

My point was that my friend who makes about $50,000 a year and his withholding from his W2 was about $7,000. He was expecting at least $15,000 back just from his solar credit, but he was shocked that it wasn't the case. The kicker is he took a big loan out to buy the system and planned to pay the principal down with the expected refund. His overall goal was to get a payment that was manageable yet still be able to pay it off in 7 years. Now his monthly payment is a few hundred bucks more a month than he had expected.

If he knew that in advance he probably would have gone the lease route or not got a system at all.

[bcroe]

Tax & credits

Not sure why anyone would want to increase their withholding. It's your money your just getting back anyways. But you're right, it could take my buddy years to get the total credit since he usually gets most of his withholding back anyways from his mortgage interest & property tax deductions. He probably only chips away about $1,000 to $2,000 per year. That'd be 7-15 years!

My point was that my friend who makes about $50,000 a year and his withholding from his W2 was about $7,000. He was expecting at least $15,000 back just from his solar credit, but he was shocked that it wasn't the case. The kicker is he took a big loan out to buy the system and planned to pay the principal down with the expected refund. His overall goal was to get a payment that was manageable yet still be able to pay it off in 7 years. Now his monthly payment is a few hundred bucks more a month than he had expected.

If he knew that in advance he probably would have gone the lease route or not got a system at all.

I have no argument with the above, but its not much like my situation. My point is, the amount I can
claim in a tax year is on my 1040 line 61, NOT line 72. Bruce Roe

[centralCalsolar]

This is really good info here. I am in the beginning stages of looking into solar for a home that will be complete at the end of this month. The builder had outrageous prices for their systems and is not a part of the programs to have the home ready for solar.

At any rate after doing some research on http://www.gosolarcalifornia.ca.gov I found that sunpower seems the way to go, although I am sure you pay for it too. I have 1 bid in with a vendor so we'll see how it goes.

I got the schematics of our roof and by my calculations I should be able to fit 18 E20 panels facing south and easily another 6 facing west which is 7.8 kW by my math but not sure if the math is that simple AC/DC etc....

Anyways thanks for all the info so far.

[russ]

T
At any rate after doing some research on http://www.gosolarcalifornia.ca.gov I found that sunpower seems the way to go, although I am sure you pay for it too.

If you are short of space then pay the penalty in additional cost for efficiency - if not then there is no real reason to pay extra.

[centralCalsolar]

If you are short of space then pay the penalty in additional cost for efficiency - if not then there is no real reason to pay extra.

That is good to know, we will see what they come back with and I suppose to should check out non sunpower vendors too. Like I said, I have room from my calcs for 18 panels facing south and another 6-9 facing west

We haven't moved in so I don't even know what to guess our usage will be either but just getting a head start.

[centralCalsolar]

So what is a good source to use to find contractors/installers for a wide eclectic mix of PV manufacturers then? Meaning not just sunpower, topsun, t-solar, solarbine etc.... but as you said, there could be better $/watt out there given a lower efficiency of the PV panel.

[centralCalsolar]

I had a meeting with another solar installer today that pushes sunpower. He had a pretty convincing argument for the extra cost of sunpower.

He was saying that on average they have more hours in the day that they take in sun. For example if a traditional panel had 5 hours in this area, the sunpower panel would be taking in 6.5 hours positioned in the same spot.

Is there any truth to this?

He quoted a 5.3kw (AC) system that generated 25.7 kW /day. well by that math, that is only 4.84 hours. He said that they undershoot the performance because they have to guarantee that it will perform what they say it will but still those numbers are quite a bit off.

So any users or installers with experience in this thought?

Does a sunpower panel produce ~20% more kW for the same Watt? Meaning comparing 2 6kW system, 1 a sunpower E20 panel system and a generic 6kW system. Would the sunpower 6kW system produce more kWs even though they are rated at the same wattage? This is ignoring panel counts, I am strictly talking watts vs watts

[bonaire]

The higher efficiency module doesn't take in more hours of sun. The total produced from a higher efficiency module is higher than a lesser module. You are paying for more power per square foot. No other magic involved. A 6kw sunpower system may need 18 modules while a SolarWorld 6kw system using 260w modules would need 23 or 24. More roof space, more racking, wiring, etc. if you are short on space, sunpower is it. Most critical thing is if you have any tree shading to work around.

You can do the math on a different module system and see if paying less for a system up front is better for your financial situation, such as ability to take the tax credit. If you are just trying to get off of higher tier rates in CA, a combination of conservation, solar, and other financial decisions can be put together and not break the bank with the largest sunpower system that will fit.

[centralCalsolar]

The higher efficiency module doesn't take in more hours of sun. The total produced from a higher efficiency module is higher than a lesser module. You are paying for more power per square foot. No other magic involved. A 6kw sunpower system may need 18 modules while a SolarWorld 6kw system using 260w modules would need 23 or 24. More roof space, more racking, wiring, etc. if you are short on space, sunpower is it. Most critical thing is if you have any tree shading to work around.

You can do the math on a different module system and see if paying less for a system up front is better for your financial situation, such as ability to take the tax credit. If you are just trying to get off of higher tier rates in CA, a combination of conservation, solar, and other financial decisions can be put together and not break the bank with the largest sunpower system that will fit.

thanks for the info, this link kinda talks about the same stuff I heard today in how sunpower panels produce more by taking in light earlier in they way they refract the light, being able to take in power from the whole module even when a small portion is covered by say a leaf or shade

http://www.solarenergyalliance.com/Sunpower.html

I have space for 18 facing south, probably another 8 facing west and 10-12 facing east so I could go with another panel and still get 8kW or more but I just thought a sunpower system say like 7kW would produce the same amount as say a 8.5kW system in a given period of time, like per month/year etc... but if that is not the case, that changes a lot of things.

So what is the above site saying when they say:

"The SunPower premium monocrystalline cell substrate enables the cell to be very sensitive to very low levels of light. The panels “wake up” the inverter earlier in the morning and continue to generate energy later in the day than other technologies."


Also, our house is new construction, still being built and there are no trees currently and nothing that will block any light for quite some time. it is also a 2 story, so I can't see a lot of stuff getting on the panels other than some bird poop or something.

[bonaire]

With all the roof angles, you may have to decide to use lesser panels and micro inverters or multiple string inverters, which increase the system price somewhat. You just need to think through the "do I really need solar?" question.

What if the power company comes to their senses and fixes the tiered rate structures? Could you be satisfied with the one largest roof array and then add more later? Are you fully able to take the tax credit? There are times when scaling back a little bit saves you in the end. Perhaps you can only get a certain sized loan or have only so much cash to spend.

My power one inverters are woken up before the sunrise and show a few watts down to sundown. I think we're talking a few watts here or there. The primary power generated by any solar array is 10am to 2pm. West and east facing probably are a waste. What is best would be 18 high efficiency modules, one good string inverter and a bit of conservation and power analysis of your usage. Which, as you say, you don't know what it will be as you haven't moved in.

Of course the federal tax credit will still pay you even if you installed the modules in your basement. Don't put up a poor performing e or w facing subsystem if it isn't going to produce well.

[russ]

"The SunPower premium monocrystalline cell substrate enables the cell to be very sensitive to very low levels of light. The panels “wake up” the inverter earlier in the morning and continue to generate energy later in the day than other technologies."

Marketing guys are entertaining people! Did they tel you if you can actually measure the difference in output due to this divine technology? Can you actually see the difference over a years time? Will it ever pay back?

You might buy SunPower because they are first class but disregard the BS sales talk.

[centralCalsolar]

Marketing guys are entertaining people! Did they tel you if you can actually measure the difference in output due to this divine technology? Can you actually see the difference over a years time? Will it ever pay back?

You might buy SunPower because they are first class but disregard the BS sales talk.

this is the kind of things I need to hear from real world people. So yes it is a good product, but only because of service and higher output per SQFT, is that the sum of it?

So yes, if I could only put 18 panels on my home, I would want to max them out.

So west facing panels are no good? I see them all the time though

[Ian S]

this is the kind of things I need to hear from real world people. So yes it is a good product, but only because of service and higher output per SQFT, is that the sum of it?

So yes, if I could only put 18 panels on my home, I would want to max them out.

So west facing panels are no good? I see them all the time though

It's not that simple especially for California where you have complex tiered electric rates that may make afternoon production more valuable than morning. As for Sunpower panels: the 20% more energy number appears to come from Sunpower documentation and relates to the slower performance degradation especially in year one:

High year one performance delivers 7-9% more energy per rated watt. This advantage increases over time, producing 20% more energy over the first 25 years to meet your needs.

see here

[russ]

You managed to find some real snake oil salesmen!

Quote, "With SunPower solar panels you can install more power in the same amount of space than with other panels, up to 50% more than conventional designs and up to four times more than thin-film solar. Our residential solar systems require significantly less roof space, so you can use fewer panels to produce the same amount of clean, renewable solar power."

Where the 50% comes from is pure blather - they are not comparing anything only making up numbers. SunPower is fine but the sales is seriously distorting reality.

[centralCalsolar]

It's not that simple especially for California where you have complex tiered electric rates that may make afternoon production more valuable than morning. As for Sunpower panels: the 20% more energy number appears to come from Sunpower documentation and relates to the slower performance degradation especially in year one:

see here

yes, both companies I have talked to in person so far set a client up on the E6 rate or "usage rate" meaning that it is more expensive in the date. There is the partial peak 10AM - 1PM which is like .30/kW and peak from 1-7 which is like .40c/kW and then back to partial till 9 but you also generate at those rates so if you were to say keep your AC off until you get home you would have generated a crap ton of power and got way ahead of yourself.... in theory.

I told them that I think it would be a good idea to get a electrical vehicle in the future when we are ready. We will be quite a few miles outside of town and I could see the benefit of using electric instead of gas in that case by sticking a few more panels on the roof to make energy for a car.

and charge the car past 9PM when it is .09c/kW