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Has anyone else had this question; What is the payback time on your solar panels?  RSS feed

 
pollinator
Posts: 537
Location: Michigan
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David Baillie wrote:I try to judge who I'm talking to before I answer.  If they drive up in a pretty nice car I turn the tables and ask them what the pay back period is on heated leather seats?)

People worth knowing will get it.  You will never convince the rest.
Humble opinion of course
Best regards, David Baillie



So much truth in the last part! Perfect.
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DIY 10KW PV Electric Payback Calculations

System Design - On Line since January 2016
10KW System set up for Net Metering ( no batteries)
32 Panels roof mounted on standing seam metal roof
32 Micro Inverters
12KW DC to AC Inverter with 25yr warranty

How Net metering works:
I use power based on the loads I present to the PV system
surplus power spins my meter backwards and my neighbors use it.
When I use more power than I'm producing the meter runs forward.
My electric bill is $0 for ~8 months per year.
A separate production meter is reported to the SREC program monthly.

Massachusetts SREC program
Pays out  0.22 /kWh average for 10 years
Average Annual payout based on 35 months of operation  $2,200/yr  

Household Power Usage
24 Months before panels  averaged 780kWh/month   $155/month electric bill
35 months with panels on line          $35/month electric bill
Electric Bill Savings                $120/month;   $1440/year

System Cost
DIY Installation (hardware only) $22,775
After 30% Federal Tax Credit $15,943

I designed and installed this system myself.   This is not reasonable for most.
A Turnkey System cost would have been 50% higher at ~ $34,000

Turnkey Installation Cost        $34,000
After 30%  Federal Tax Credit $23,800

DIY System Payback
$15,943/($1,440 annual Elec bill savings + $2,200 SREC annual payout) = 4.38 years with SRECs
$15,943/$1,440 annual Elec bill savings= 11.07 years without SRECs

5.6 years remaining SREC payouts = 5.6*$2,200= $12,320
$12,320/$420 annual elec. bill = 29 years with no elec. bills after system is paid off.

Turnkey System Payback
$23,800/($1,440 annual Elec bill savings + $2,200 SREC annual payout) = 6.5 years with SRECs
$23,800/$1,440 annual Elec bill savings= 16.5 years without SRECs


Cost and efficiency losses not included the above calculations:
~ 6 weeks of design and installation work, this being my first and only design.
Panel peak power out drops ~ 3 %/yr and tapers off at about 70%
Estimated End of Panel Life is 25 years
Maintenance costs, to date these have been $0

Hardware costs keep dropping 2-3% /yr , these costs are based fall of 2015 prices
 
Posts: 48
Location: Northern michigan
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A great way to get hot water is a tankless on demand gass heater uses about 1/6 the gass if not less
As for solar its almost never a bad idea the rule of thum is the more you have the faster they pay themselvs off
Even if they pay you back to slow it will not matter as the value of your home jumps up big time my gass and electric bill togather with solar and a tankless heater was about -80 to +10 durring spring summer and fall and i got a credit that added up till winter hit and my first 3 or 4 heat bills were free
 
pollinator
Posts: 2385
Location: Massachusetts, Zone:6/7, AHS:4, Rainfall:48in even Soil:SandyLoam pH6 Flat
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Jim St Laurent wrote:DIY 10KW PV Electric Payback Calculations

System Design - On Line since January 2016
10KW System set up for Net Metering ( no batteries)
32 Panels roof mounted on standing seam metal roof
32 Micro Inverters
12KW DC to AC Inverter with 25yr warranty

System Cost
DIY Installation (hardware only) $22,775
After 30% Federal Tax Credit $15,943

DIY System Payback
$15,943/($1,440 annual Elec bill savings + $2,200 SREC annual payout) = 4.38 years with SRECs
$15,943/$1,440 annual Elec bill savings= 11.07 years without SRECs

5.6 years remaining SREC payouts = 5.6*$2,200= $12,320
$12,320/$420 annual elec. bill = 29 years with no elec. bills after system is paid off.

Hardware costs keep dropping 2-3% /yr , these costs are based fall of 2015 prices



Panels are now 50cent/watt. 60cent/watt with feight shipping+tax included.
Electricity is $0.22/kwh for production PLUS $0.22/kwh for distribution so it is actually $0.44/kwh.
 
Posts: 460
Location: Rural Unincorporated Los Angeles County Zone 10b
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Michael Bushman wrote:Another thing against solar is that most of us here have fairly low energy usage.



You're totally right, Michael.
I've been an electrician for 40 years and can have anything electrical I want. We don't have solar because we don't need it. Solar is perfect for people who consume a lot of electricity. The more they use, the better deal it becomes.
 
pollinator
Posts: 283
Location: Denmark 57N
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I considered solar for hot water, but the payback would have been nearly infinite as our hot water comes from the central heating boiler which is wood fired, and wood can be found very cheap or even free if you look hard enough. the reason I was thinking of solar hot water was so I didn't have to fire up the boiler in summer to have a shower, but the price. ouch because the hotwater tank on the boiler is built in we would need one of them as well, and between that, the panels and installation (legally has to be done by a professional) the price was horrific it would never pay for itself.  The "official" count on how long a electrical solar array takes to pay for itself here in Denmark is between 11 and 22 years depending on roof and usage. Basically not worth it at all.

 
pollinator
Posts: 551
Location: Southern Illinois
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Many years ago I went shopping for home PV solar systems.  I went so far as to find a contractor who had tax credit worked into the final price.  I will spare you all the details, but the payoff time came in at 25 years—for a system that replaced only 1/2 the electrical demand.  It was as very bitter pill to swallow.  I wish you better luck than I had.

Eric
 
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