Considering Solar

skgolfer

Hi All

I live in NJ and am considering installing a system. It is a 10k system. NJ seems to have a pretty good program with rebates and RE credits on top of the 30% from the Federal Govt. The cost I am being quoted from 2 different firms is about $6.30 per DC watt so at 10K that works out to $63,000 installed. Cost after rebates about half that. Then through ongoing RE credits and savings on electricity, both companies are saying the system will provide about a 4 year payback. Any thoughts? Am I missing something?

Thanks.

icarus

Re: Considering Solar

I'm certainly not an expert on grid tie,, but 4 year pay off sounds optimistic.
If you go here :http://www.pvwatts.org/ you can plug in real numbers with your location and get a pretty good idea of what any given system might yield.

Tony

n3qik

Re: Considering Solar

An 10K system is pretty big, but with a 4 year payback, not bad. Most of us have to cut our loads in half to get the system within a reasonably cost/payback. Good luck and keep us posted.

BB.

Re: Considering Solar

Using the PV Watts program and assuming you are closest to Binghamton NY, 10 kW system installed on an optimal roof pitch facing near south (see program results):

[FONT=Fixedsys]Results

Month
Solar Radiation (kWh/m2/day)
AC Energy (kWh)
Energy Value ($ at 14.5 ¢/kWh)

1      2.88          717        103.97   
2      3.84          869        126.01   
3      4.36          1060        153.70   
4      4.77          1081        156.75   
5      4.97          1114        161.53   
6      5.09          1077        156.16   
7      5.22          1120        162.40   
8      5.20          1132        164.14   
9      4.33          929        134.71   
10      3.92          901        130.65   
11      2.57          593        85.98   
12      2.07          500        72.50   
================================================
Year    4.10        11093     $1608.49   [/FONT]

So your out-of-pocket expenses should be $31,500 installed:

$31,500 / (11,093 kWhrs per year * 20 years) = $0.14 per kWhr amortized over 20 years

$31,500 / ($1,608.49 worth of electricity per year) = 19.58 years

The above pay back period assumes $0.145 per kWhr based on how much energy such an array would produce over an average year. If you have other incentives (one year net metering, Time of Use billing, etc.), you may see a quicker payback.

Also, what is your average power rate--in California, we have tiered rates that range from less than $0.08 per kWhr to over $0.60 per kWhr--depending on rate plans, usage, time of use, season, residential/commercial, etc.

The system would produce about 500-1,100 kWhrs per month... What does your home use (by season?).

Under 300 kWhrs per month (with natural gas) is pretty low. Average, around 1,000 kWhrs per month. Places with heavy A/C usage are around 1,500-2,500 kwhrs per month (summer).

You may have other expenses too (perhaps 1 replacement $5,000+ inverter in that 20 year period, etc.). And, you need to check if your locality charges property taxes on your solar array (some states have very punishing property taxes and may not exempt solar arrays).

Don't get me wrong--$0.145 per kWhr is not a bad price for Grid Tied solar... Especially in the North East where you may not have as much sun.

-Bill

Aussie Bob

Re: Considering Solar

skgolfer wrote: »

Hi All

I live in NJ and am considering installing a system. It is a 10k system.

That's a nice system. 8)

. . . Then through ongoing RE credits and savings on electricity, both companies are saying the system will provide about a 4 year payback.

What are these "ongoing RE credits"?

JeffreyDV

Re: Considering Solar

I just had a 9.72kW system installed in Northern, NJ. My installed cost was $7 per watt. I received a $1.75 per watt upfront rebate from the state. I am predicting a ROI of about 6 years. This is made possible mainly by use of NJ's SREC program which gives you 1 credit for every 1000kWh of generation. Currently, the credits are trading for about $675 each. I havent set up my SREC account yet so I do not know what the expected generation will be. For systems under 10kW they estimate generation rather than use actual generation figures. FWIW, my average electric bill was $180 per month.

skgolfer

Re: Considering Solar

Thanks All for your feedback. Jeff, have you checked what the impact on your real estate taxes would be if any? Thanks.

JeffreyDV

Re: Considering Solar

skgolfer wrote: »

Thanks All for your feedback. Jeff, have you checked what the impact on your real estate taxes would be if any? Thanks.

It is against state law for the town to raise your property taxes because of a solar installation.

niel

Re: Considering Solar

not for all states that i'm aware of.

JeffreyDV

Re: Considering Solar

niel wrote: »

not for all states that i'm aware of.

I know in NJ it is.

System2

Re: Considering Solar

I hope I'm wrong, but I thought you got a credit after after 1000Kwh solar production. No at 17Kwh per year thats a long time to get one credit.

BB.

Re: Considering Solar

Vern2,

It all depends on where you live and what utility you are connected too... Guessing you are in Arizona--which tends to have cheaper utility power...

This website will point you to many of the major rebates/credits/laws for your area:

www.dsireusa.org (USA only)

-Bill

System2

Re: Considering Solar

I am in Illinois and pay ComEd a bit less than 8 cents per kwh. I use about 25000 per month in one loacation and 32000 per month across town at another location. I can not do the math to make solar a meaninful investment dispite 30% from feds. The State of Illinois does offer 30% rebate as well but is unfunded. But if funded it is still near impossible to make solar an esay economic choice.

Has this forum developed and rules of thumb to calculate this? To be honest I would like to start a business with solar but do not see a market for it here.

amby

Re: Considering Solar

SKG and Jeff,
I am in Mercer county. took 3 quotes and all quoted around $7/watt which is HIGH by my estimates. I expect it to be around $6/W
my calculations also show 4-6 year payback because of the SRECs. I am thinking of putting 36 Kyocera 210W panels.

here is no property tax and no sales tax. 30% Fed I-tax credit and $1.75/W NJCEP rebate.

do you mind giving me reference of your installer?
thanks

amby

Re: Considering Solar

Thanks Jeff.
yes, it is difficult finding someone to do it cheap but I am trying :-)
here is a real actual quote for ALL the material. I am asking installers to be honest about what they are charging for.

http://lib.store.yahoo.net/lib/wind-sun/10kw-gridtie.pdf

niel

Re: Considering Solar

guys, this type of info should be done via pm. you may be just trying to help each other, but it is hard to differentiate this from those trying to plug their spam spots into the forum and as such i have edited jeff's post. seeing as how it is windsun's forum, the naws info shall stand unless he wishes to edit it out.

tallgirl

Re: Considering Solar

amby wrote: »

Thanks Jeff.
yes, it is difficult finding someone to do it cheap but I am trying :-)
here is a real actual quote for ALL the material. I am asking installers to be honest about what they are charging for.

http://lib.store.yahoo.net/lib/wind-sun/10kw-gridtie.pdf

You're also asking installers to write you a bill of materials that you can then use to do the installation yourself, or hire out to someone else on the cheap who wouldn't know a combiner box from a combine reaper.

I've worked with installers to design large and/or weird systems and it takes time for them to put together a list of "everything". You tell me how much power you want, when and where, and I can get that part right and cut you an invoice for my efforts. But if you want me to tell you all the parts that are going to go into that system, you're going to pay me for a couple more hours of my life.

And for what it's worth, $7 / watt installed isn't bad. $6 / watt usually requires cheaper materials or an installer who's in financial troubles, needs the work badly, and might not be around in a year or three. The only time you might legitimately get to $6 / watt is when it's a long and boring install with plenty of panels all set up exactly the same, string after string after string.