Switching To Solar Power, One Year Later

ThinSkin writes "Slashdot readers may recall Loyd Case's series of articles illustrating his experiences after switching to solar power for his family home. Loyd shared his one month update, a six month update, and now finally concludes his series after one year of solar power. Despite the $38,000 initial cost for the setup, Loyd is very optimistic after a $3,000 savings in one year, meaning that in about 12 years he will break even — though he suspects ten years is a better estimate considering other factors. Other reasons such as feeling 'green,' increasing the property value of his house, and the 'spousal acceptance factor' all support Loyd's decision on why he'd do it all over again if he had to." The article is spread annoyingly over multiple pages, like everything at the site, and the print version omits the graphs.

Comments

Industy Standard Warranties

[spun]

Most manufacturers guarantee that their panels will give at least 90% of peak power at ten years, and 80% of power at 25 years. Yes, he's saving money.

I'm in my 5th year and have statistics

[skidisk]

I deployed solar panels when I replaced my roof in 2004; the total out of pocket cost after state rebates and federal and state taxes was $14,612. The system generates about 15 KwH on a good day; I live in a tract home in Mountain View, CA. So far, the panels have generated 19,225 KwH, which reduced my energy bill by $10,392 as of May, 2009. I've not seen the expected degradation in the power production, but it's difficult to measure due to changes in the weather -- it's entirely possible that 2004-2005 were cloudier than 2007-2008, or something like that. In any event, the system has delivered between 3819 and 3930 KwH every year. I'm extraordinarily happy with the way this has worked out.

Re:Return on investment

[Space cowboy]

Panels generally last 25 years at which time they're at 80% of their initial efficiency.

I spent $78k (with no loan, so no extra payback) putting solar panels on my house late last year. My highest bill (August last year) was ~$1000 and I was averaging ~$700/month over the year; my May bill this year was $49. I estimate payback for my system to be ~10 years or so. There's a few things to consider if you're thinking of doing it yourself:

• The cost of electricity is only going up. If you graph it over time, it's been steadily increasing for the last 10 years or so in my area (Bay area, CA)
• You put yourself on the 'expensive electricity in the day, cheap electricity at night' and get a meter that sells your over-production back to the utility
• It puts a significant value on the house should you want to sell it, because the new owner gets to spend less per month on electricity.
• Your state will give you a chunk of change back (I got $15k or so) if you invest in solar power for your house
• You'll also get a 30% tax credit (ie: taken off your tax bill, not off your earnings-before-tax) if you go solar this year. Last year it was capped at $2k, so I lost out on ~$20k. Oh well.
• The more electricity you use, the more expensive each unit becomes. The cost of the top 50% of my electricity-use per month was costing 2x as much as the bottom 50% because prices are tiered. If you can get yourself out of that top-tier, it can really be worth it.

We use a lot of electricity. This is a nice, green way to offset that and still have the toys I like (heated swimming pool, air-conditioning, pond in the back yard, server-room in the garage,...). Example: last month (1st May -> 31st May), the power production (I have the monitoring system all set up :) was 1,260 kWH. That matches nicely with our average 40 kWH/day with air-conditioning on. And if it's not being soaked up by your solar panels, it's just warming the roof and causing your air-con to go into overdrive... :)

The payback calculation is pretty easy. Maintenance is essentially zero, so total cost including permits, installation, etc. was ($78k - $2k - $15k) = $61k. Savings per year are ~$6000. Payback in ~10 years, assuming electricity costs are static (unlikely) and after that it's all gravy :)

Simon