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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."
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.
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.
Try Europe where you can get 35 hour work weeks and 35% unemployment.
I guess that the statistics would disagree, but why let facts get in your way!
Ahhh, what an awful dream. Ones and zeroes everywhere... and I thought I saw a two.
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.
Find free books.
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!
Grid tie equipment is required to have automatic disconnection systems. Also, the linemen can pretty much wave a wand at the lines to see if they are live or not...
Nerd rage is the funniest rage.