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Switching To Solar Power – One Month Later
ThinSkin writes "After an interesting article on solar panel installation for the home, Loyd Case at ExtremeTech has written a follow-up after about a month of normal use. Posting an $11.34 electric bill (roughly 3% of previous months), Loyd shares his experiences using solar power and how it can be fun for the geek, with computer monitoring services and power generation data. Of course, solar power isn't all fun and games, given the amount of required maintenance — even unpredictable maintenance, like wiping off accumulated ash from fires in Northern California."
... even though it was raining cats and dogs today. I'm still using it withou
According to the article California will not allow homeowners to sell more power back into the grid than they are buying. He doesn't say why. I don't understand the reasoning for such a restriction, since the possibility of selling more than you buy would encourage wider adoption.
If 'the people' in Amendment 2 are 'the state' then Amendments 1, 2, 4, 9, and 10 benefit the state, not you.
trix are for kids mutherfucker!
That's right and responsible energy use is for adults. I like to see things like this, and as some might decry the amount of involvement one must provide to effectively commit to a project along similar lines. Though I personally think people (especially in the U.S.) could really benefit from having to be more involved in the production and usage of the energy they consume.
On the Oregon Cost born and raised, On the beach is where I spent most of my days
From TFA:
So he saved about $330/month. It cost him $36K (which really cost $50K, but let's say). So it'll take 109 months to get back the money, or 9 years, not adjusting for inflation and investment opportunity cost. Let's say that brings it up to 12 years. Not including maintenance and repairs. It might even need complete replacement at that point. At 50K, which is the real cost, we're talking more like 16-18 years.
That's still a bit too long an investment for this to be really practical. Prices need to come down to about a four year payoff before I'd be really interested.
On another subject, I'm kind of glad to see someone who actually uses more electricity than I do. :)
Sometimes it's best to just let stupid people be stupid.
2. Are they bolted on? Any locking mechanisms?
3. Is it easy to climb on to the roof?
4. Do you have good access to a road from the home?
5. When are you planning to take a vacation?
6. Does it have any kind of GPS thingie or Wifi thingie attached that will phone home?
Thanks buddy.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
There are indeed losses, but much less than you propose. Most solar DC to AC inverters are 90-93% efficient in their conversions - so only a 7-10% loss. http://www.beaconpower.com/products/SolarInverterSystems/docs/M4_M5_plus_datasheet_web.pdf The same goes for the conversion back to DC on the equipment side.
Residential solar installations typically have no batteries, so there is no maintenance cost for batteries, nor replacement costs. This type of installation uses the grid as a kind of giant battery, feeding power to the grid during the day and drawing from the grid at night.
1. They are somewhat heavy (50 lbs). They are awkwardly large at 5ftx3ft. Two person job if you don't want to risk a rooftop fall.
2. They are typically bolted on. Uninstall time will be in the several minutes per panel range. Be sure you have an electrician with you to avoid death by electric shock.
3. You can see in the pictures he has a typical roof. Bring a ladder. And a crane if you want an easier time lowering the panels.
4. Yes, see the pictures.
5. Don't know about that one. Probably end of December or next summer.
6. Doubtful.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
You forgot to engage the hydropower backup generator.
Oh, yeah, it's not easy to pad these out to 120 characters.
Yea, I was shocked at how much energy the family in this article uses. My GF and I average ~370kWh/month, 4,440kWh/year. We live in Mountain View, which is the next small city over from Sunnyvale. The family in this article is using 17,400kWh/year. If he expects a 20% drop in usage when the family becomes 2 people, that's still THREE TIMES what we use. I also have a home server and network.
By coincidence, today is the day I got my first yearly bill for my new photovoltaic system. Where I live (Orange County, CA, with Southern California Edison as my utility), people who have residential PV systems get billed yearly rather than monthly. A year is also pretty much the minimum amount of time for which you need data in order to find out how your system is performing, since both your energy production and your energy use fluctuate seasonally.
My bill for this year was $353.63. The system is nominally 4.4 kW, and cost $28k after rebate. It's covering about 90% of our use, which was almost exactly what we shot for -- if we produce more than we use over 12 months, they don't pay us for the excess.
People always want to know the number of years until the system pays for itself. Basically that's utterly impossible to predict. There's a reason that they exclude energy from the consumer price index -- it's because energy prices are extremely volatile. If the increased price of fossil fuels starts to be reflected in the cost of electricity, then I'm going to look like a financial genius. The other thing that's completely unknowable is how fast the technology will progress. If there's a breakthrough in technology five years from now, and the price of panels per kilowatt comes down by a factor of two, then I'll wish I'd waited. It's also kind of funny hearing the quick-buck psychological attitude a lot of Americans have toward investing money in something like this; from the way people talk, you'd think they were going to take that money that could have gone into photovoltaics and invest it in some kind of magical pixie dust that was guaranteed to pay a steady 20% annually until the end of time. And finally, beware of anyone making blanket statements about whether PV is ready for prime time or not. It completely depends on factors like the price of electricity in your area, which way your roof faces, your latitude, the amount of cloudy weather, and the amount of shade. PV is like Linux: it's ready for prime time for some people, and it's not ready for prime time for other people.
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isn't civilization, and the fact that you think it is indicates a deeply flawed view of the world.
He says he put in $36,000 and will save $3,300 per year in payments to the power company. Now the historical annual rate of return of an S&P 500 index fund is 11.3% over the last century, so $36K put there would return over $4,000 -- enough to pay the $3,300 to the grid, have $700 left over and of course, still keeping the principal.
You're comparing apples and oranges here. If people always invested solely based on maximizing the expected average rate of return, then bank CDs wouldn't exist, bonds wouldn't exist, real estate and REITs wouldn't exist, etc. In reality, people are balancing the expected rate of return against variability. The reason bank CDs are paying something pathetic like 4% right now is that the banks have to guarantee that they'll pay you 4% on your money. The bank is essentially charging you for insurance against negative variability. Although there are a lot of unknowns involved in buying PV (what will electric rates do in the future? how much will the technology improve), they're a lot less than the unknowns involved in stocks. My S&P 500 index fund is down 19% from its peak value last year. There's a reason that most people build a balanced investment portfolio that includes both stocks and bonds; it's because mixing volatile and nonvolatile investments is a way of maximizes your expected rate of return for a given amount of risk that you're willing to accept.
And grid power might go up, but only so far. Because eventually the grid power hits the solar price, and the grid itself starts putting in solar sources at that price -- because it's cheaper.
Your logic doesn't work. When you own a PV system, you're part of "the grid itself." When I'm at work during the day, my PV panels are pumping energy into the grid, which is selling it to other customers. In my area, grid power has hit the solar price, for a south-facing roof with no shade; that's why I, a homeowner with a south-facing roof and no shade, have put in a PV system. You seem to be assuming that if rates go above a certain threshold, the entire state of California will suddenly magically cover itself with PV panels, because that will be the right thing to do according to the laws of supply and demand. That doesn't make sense, for a couple of reasons. First, there are huge variations in the price of land, the local cost of electricity, the amount of sunlight, which way people's roofs face, and how much shade they get. Second, there's a barrier to covering every house with PV panels, which is that most homeowners are short on capital. Your idea that the whole grid would suddenly go solar at some threshold is like imagining that everybody will suddenly drive a hydrogen-powered car if gas goes over $6 a gallon. We're talking about a massive infrastructure that doesn't change overnight.
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Guys -- you all seem to be neglecting the recent developments in solar financing.
(Disclaimer -- I do work for SolarCity http://solarcity.com/, a leading installer of residential solar arrays in the SF Bay Area and beyond. I won't make a totally shameless plug here, I'm trying to be fair to the other good and clever solar companies out there. A rising tide lifts all boats!)
By bringing in a 3rd party commercial owner via an Operating Lease or Power Purchase Agreement (PPA) structure, the customer can save money from solar on Day 1.
The 3rd party (an investment fund, or perhaps the solar company themselves) owns the system and claim the full range of available incentives. As opposed to residential owners, commercial owners can take accelerated depreciation on the system, and can take the full 30% federal tax credit (rather than facing a $2k cap), and they also get whatever state/local/utility incentives are available as per usual. The customer has a low (or zero) down-payment, and makes monthly payments over a period of ~15-18 years. The tax investor receives a reasonable return on their investment over time, the installer makes reasonable margins on the installation, and the customers can save money from Day 1. Everybody wins!
So to use the parent submitter's house as an example of what we can do -- For a $300/month average bill in Sunnyvale, CA, we might recommend a 7kW DC system. Assuming the customer had decent credit (720 FICO), we would require no down payment, and then charge monthly lease payments of $181/mo, for 15 years. The monthly payments do go up at 3.5% per year (we could alternatively have 0% escalation, but of course that would require a higher starting payment and so it's harder to show savings right away... there are many possible variations here. Also remember that local PG&E utility rates are increasing at >5% per year on average).
With this 7kW system, they might expect their average monthly bill to go from $300 to $72 per month. Add the $181/month payment, and their new average monthly electricity cost is (181 + 72) = $153/month, for immediate savings of ~$47/mo!!
The installers offering these plans usually offer full service/maintenance for the life of the lease, including replacement of the DC/AC inverter if necessary.
The customer is given the opportunity to purchase the system after years 6/10/15, or if they have to move or sell their house. The panels are warranted by the manufacturers to last 25+ years, so a long-term buy-and-hold strategy is solid. Or, if the customer looks around in 15 years and sees a better/cheaper technology, or just doesn't wish to renew or buy out), they are free to end the lease and we'll remove the panels at our cost.
The customer who understands Net Present Value (NPV) calculations can easily demonstrate that this offers far superior savings compared to either a) doing nothing, or b) purchasing the system for cash.
So before you all roll your eyes about solar being a poor investment with a 12+ year paybacks, please consider such alternative financing approaches.
I put a 3kw system on my roof in February, 2005. (I live in Silicon Valley). My electricity bill has been zero since then -- well, actually, $60/yr in some fee PG&E charges. My total electricity cost for the previous three years (2002-2004) was $6,730. Installation of the solar panels cost a net of $13,369 after rebates. So I've saved 50% of the cost already, and my house is worth more due to the presence of the solar power array. I took advantage of California rebates which were higher then than now, though, so that's a bummer.
in terms of measuring live solar data, there's an open source project at: http://www.solarnetwork.net/ that is collecting and charting live data from Outback, MorningStar and Xantrex devices. let me know if anyone has an interest in participating, or leave a note on the site. thanks!
According to the Wall Street Journal the S&P500 from 2000-2007 only returned 1.6%, and if you include the absolutely dismal 2008 (thru June) economists are already calling this the "lost decade" since returns over the past 10 years are pretty flat. Worse when you factor inflation. With returns like that, solar panels would've certainly been the better investment. At the least, you wouldn't be as subject to local Edison's blackouts and other various fiascoes, which for some reason seem to be getting more and more common and taking longer to fix each time.
Just the thought of being independent from the local power grid woes is pretty appealing.
{ - Generic Guy - }
Having socalised healthcare costs a lot of money.
Not having socialised healthcare costs a lot of humanity.
Your call.
It's been a long time.