Calculating price per watt

[point1]

Hello all,

I'm fairly new to this and have begun my research. I live in Norco CA (92860) and I have begun to engage and solicit proposals from about 6 Solar companies.

I am looking to purchase rather than lease and likely will go with the HERO program to take advantage of tax benefits.

I have narrowed it down between Solarworld and Sunpower and reading all about Solarworld's solvency issues, I think Sunpower is probably the route I am going to go with.

My average SCE bill a month is about $415.00 a month average usage of 1,688.58 kw

I have about three proposals in so far..

Company A - Sunpower 327 Watt panel system at 7.194 priced at $31,474 after tax credit
Company B - Sunpower 327 Watt panel system at 9.156 priced at $33,168 after tax credit
Company C - Sunpower 327 Watt panel system at 9.81 priced at $32,003 after tax credit

As I understand it, to calculate price per watt for the solar system, I would take the price (not sure if I calculate prior to the tax credit or apply it then calculate) and divide it by the expected output of the system

so for Company A - $31,474/7194 = $4.38 per W
Company B - $33,168/9156 = $3.62 per W
Company C - $32,0003/9810 = $3.26 per W

Are my calculations correct? Also do I do it post the tax credit or prior? I do plan on applying the full tax credit to the loan amount.

thanks!

point1

[sensij]

Edit Your calculations are *not* correct. See below.

Why the difference in array capacity? Do you know how much energy you use annually, and how much offset each system will provide?

I'm not sure what you mean by SolarWorld's solvency issues. They had trouble in 2013, but the more recent press has generally been positive, and they were back to pre-tax profitability in 2014 (yeah, still unprofitable, but it sounds better), and expect 2015 to be in the black.

That aside, there are plenty of alternatives to Sunpower that are likely to cost less, although both of the larger systems you were quoted have prices that may be competitive.

[point1]

Your calculations are correct. Why the difference in array capacity? Do you know how much energy you use annually, and how much offset each system will provide?

I'm not sure what you mean by SolarWorld's solvency issues. They had trouble in 2013, but the more recent press has generally been positive, and they were back to pre-tax profitability in 2014 (yeah, still unprofitable, but it sounds better), and expect 2015 to be in the black.

That aside, there are plenty of alternatives to Sunpower that are likely to cost less, although both of the larger systems you were quoted have prices that may be competitive.

one company says to start small then add to the array. Another's philosophy is to wipe out the electric bill entirely.

I am also making moves to lower my electric usage.. mainly upgrading my pool pump to a more efficient one and also changing out all my lights to LED.

Are the prices for Sunpower that I listed competitive? Also what alternatives to Sunpower should I consider? I heard all good things about Sunpower and "American made" is one selling point

[point1]

this is my 2014 usage that I compiled from SCE

January $309 1284 killowatts
February $294 1221 kilowatts
March $356 1440 kilowatts
April $324 1441 kilowatts
May $452 1739 kilowatts
June $377 1675 kilowatts
July $494 2068 kilowatts
August $466 1993 kilowatts
September $668 2680 kilowatts
October $432 1742 kilowatts
November $447 1665 kilowatts
December $346 1316 kilowatts

[sensij]

one company says to start small then add to the array. Another's philosophy is to wipe out the electric bill entirely.

I doubt that either of those philosophies is a universally good idea. With SCE, you should be aware that your net metering agreement is protected for 20 years, unless you expand the system by more than 10%. If so, your new agreement will be subject to the terms at that time. The successor to net metering is still being studied / negotiated, but will take effect 7/1/2017.

100% offset is also unlikely to be the most cost-effective installation. The cost of baseline tier electricity may be going up, but even at the higher prices that are being projected it will still take much longer for panels that offset that electricity to "break even" in the way many people define it (10 years or more). If you guess at what 100% offset should be but use a little less electricity or generate a little more than expected, the excess is only worth $0.04-$0.05 / kWh. In my opinion, aiming for a bit less than 100% offset is likely to be the best use of cash, although differences in projections and opinions can certainly lead to other rational conclusions.

I am also making moves to lower my electric usage.. mainly upgrading my pool pump to a more efficient one and also changing out all my lights to LED.

Are the prices for Sunpower that I listed competitive? Also what alternatives to Sunpower should I consider? I heard all good things about Sunpower and "American made" is one selling point

Yes, I would consider those Sunpower quotes competitive for those panels. Other lower cost panels (besides Solarworld) you might want to consider include LG, Canadian Solar, Renesola, Suniva, Hanwha, Hyundai, Trina, etc, etc. I can send you information on the installer I'm using, if you would like.

[J.P.M.]

Hello all,

I'm fairly new to this and have begun my research. I live in Norco CA (92860) and I have begun to engage and solicit proposals from about 6 Solar companies.

I am looking to purchase rather than lease and likely will go with the HERO program to take advantage of tax benefits.

I have narrowed it down between Solarworld and Sunpower and reading all about Solarworld's solvency issues, I think Sunpower is probably the route I am going to go with.

My average SCE bill a month is about $415.00 a month average usage of 1,688.58 kw

I have about three proposals in so far..

Company A - Sunpower 327 Watt panel system at 7.194 priced at $31,474 after tax credit
Company B - Sunpower 327 Watt panel system at 9.156 priced at $33,168 after tax credit
Company C - Sunpower 327 Watt panel system at 9.81 priced at $32,003 after tax credit

As I understand it, to calculate price per watt for the solar system, I would take the price (not sure if I calculate prior to the tax credit or apply it then calculate) and divide it by the expected output of the system

so for Company A - $31,474/7194 = $4.38 per W
Company B - $33,168/9156 = $3.62 per W
Company C - $32,0003/9810 = $3.26 per W

Are my calculations correct? Also do I do it post the tax credit or prior? I do plan on applying the full tax credit to the loan amount.

thanks!

point1

I'd suggest don't do anything yet.

At 20,263 kWh/yr. you will be much further ahead if, before solar, you get an energy audit and use some of the HERO financing to pay for conservation improvements such an audit recommends. After that, consider replacing all but the lowest tiers of a REMAINING bill as more cost effective than a 100% offset.

Sunpower may be around, but you'll pay a hefty upfront premium for very similar performance from other equipment that will, in all likelihood be around as well. LG. Kyocera and lots of others come to mind. Broaden your equipment selection possibilities.

I'm not sure of your numbers vs. how you are describing your understanding of price per Watt calc. Nameplate Watts and kWh/year expected output are two different animals. It looks like Company A is quoting you a 22, Sunpower 327 Watt/panel system at $31,474 total price before tax credit (?). Company B and C's pricing seems very low for Sunpower equipment. Are you sure those are for Sunpower equipment and not Solarworld ? Those look more like Solarworld prices. $ 4.38/Watt for S.P. is believable. $3.62 or less for S.P. is a real stretch for me.

HERO can be a real way to finance.

The common way to calculate the price per Watt: divide the total system price BEFORE any tax credits by the system size in nameplate Watts. Thus, a 5,000 watt system consisting of 20, 250 Watt panels that costs $18,000 before tax credits has a per Watt cost = $18,000/5,000 = $3.60/Watt.

For your location, a mostly south facing array at a (common) 20 deg. tilt and minimal shading will probably produce something like 1.6 to 1.7 kWh/yr. per. nameplate Watt. Thus, a 5 kW array will put out something like (5,000) X (1.65) = 8,250 kWh/yr.

A SWAG to offset 20,263 kWh/yr usage: 20,263/1.65 = ~12,280 Watt system. That's a pretty big system. I'd respectfully suggest you are a serious candidate for an energy conservation intervention.

Going prices around here are something like: S.P. at, say, $4.50/Watt = ($4.50) x (12,.280) = 55,263
Solarworld at, say, $3.60/Watt = ($3.60) X (12,280) = $44,208.

Both less 30% fed. tax credit. Caution: You'll have 2 tax years to burn through a pretty hefty tax credit. Some tax planning may be required.

[sensij]

Sorry, I misread the original post, and edited my response. The calculations, as J.P.M. suggests, are not correct. The correct calculation is the price paid (pre-rebate) divided by the DC rating (STC) of the system. The Sunpower prices are higher than I thought on first read, and probably only competitve with other Sunpower installations, but not with installations using less expensive equipment.

[point1]

Sorry, I misread the original post, and edited my response. The calculations, as J.P.M. suggests, are not correct. The correct calculation is the price paid (pre-rebate) divided by the DC rating (STC) of the system. The Sunpower prices are higher than I thought on first read, and probably only competitve with other Sunpower installations, but not with installations using less expensive equipment.

ok I'm revising my calculation pre-tax credit

Company A - $44,962/7194 = $6.24
Company B - $47383/9156 = $5.18
Company C - $45719/9180 = $4.98


How do these figures look now?

[J.P.M.]

ok I'm revising my calculation pre-tax credit

Company A - $44,962/7194 = $6.24
Company B - $47383/9156 = $5.18
Company C - $45719/9180 = $4.98


How do these figures look now?

They look WAY high !

Sunpower can be had for ~ $4.50/Watt pre tax credit.

For the same performance, lots of other decent equipment probably equal to S.P. durability can be had for ~~ $3.50 to $3.75/Watt +/- a bit. Shop around. Some on this forum can PM you vendors if you wish.

Do as you wish, but I'd suggest the conservation measures first, otherwise any system you get will be oversized (and thus overpriced) based on an oversized, prior load that no longer exists. By some standards, that is a waste of money and resources.

[silversaver]

very high

[point1]

very high

Ok that settles it then, the companies that I solicited proposals are pricing their systems and installations way high.

Can someone please recommend 3 or 4 good socal companies?

and yes I am going to address my electricity usage, upgrading or replacing my pool pump and upgrading my 10 year old central air. Amongst other things that I need to do to save energy.

thanks!

[scrippsbruin96]

Ok that settles it then, the companies that I solicited proposals are pricing their systems and installations way high.

Can someone please recommend 3 or 4 good socal companies?

and yes I am going to address my electricity usage, upgrading or replacing my pool pump and upgrading my 10 year old central air. Amongst other things that I need to do to save energy.

thanks!

I figured out the local subcontractor some of bigger companies use, yelp'd and realized the subcontractor has a great reputation and history, and went with them directly. Using generic panels, my upcoming install is priced at $2.97/watt. PM me if you are in the SD area.

[J.P.M.]

Ok that settles it then, the companies that I solicited proposals are pricing their systems and installations way high.

Can someone please recommend 3 or 4 good socal companies?

and yes I am going to address my electricity usage, upgrading or replacing my pool pump and upgrading my 10 year old central air. Amongst other things that I need to do to save energy.

thanks!

Point 1: Check your P.M.'s.

[J.P.M.]

I figured out the local subcontractor some of bigger companies use, yelp'd and realized the subcontractor has a great reputation and history, and went with them directly. Using generic panels, my upcoming install is priced at $2.97/watt. PM me if you are in the SD area.

OP is in Riverside co.

[point1]

thank you guys! I really appreciate the feedback.


Has anyone here heard of Stion?