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Switching To Solar Power — Six Months Later

ThinSkin writes "Slashdot readers may remember an article regarding ExtremeTech's Loyd Case's experiences with solar power for the home after one month of usage. During that time six months ago, it sure seemed like a great deal, but the tables have turned significantly once winter approached. While it's no surprise solar power generation is expected to dwindle during the winter, Loyd compares solar power data of the last six months to determine if solar power is still worth the time and money."

7 of 591 comments (clear)

  1. Re:$400 a month? by dfdashh · · Score: 5, Informative
    Here's why, from his initial article:

    Our power usage is unusually high for a typical, four person nuclear family. A big part of that is because I have a PC lab and network in the basement. Both my wife and I work out of the house much of the time, with her time almost 100% in the home office. Plus, we have two teenage girls and a pretty beefy HDTV and home audio setup in the family room.

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  2. Re:$400 a month? by Muad'Dave · · Score: 4, Informative

    Restrictions on the installation of DirectTV and other satellite dishes are explicitly preempted by FCC regulation in the US.

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    Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
  3. Re:$400 a month? by drunkennewfiemidget · · Score: 5, Informative

    The house I currently live in was powered with solar panels here in Southern Ontario before I bought it. The guy who sold it to me took the panels with him. They did just fine at consolidating his hydro to the point where he was paying almost NOTHING to the power company. They're not worthless at all. A large investment that might take longer out here to recoup costs, but definitely not worthless.

  4. A sun-tracking system is better by msbmsb · · Score: 5, Informative

    MAKE:blog has some descriptions of some DIY sun-trackers to move the panel with the sun during the day.

  5. Re:$400 a month? by MoonBuggy · · Score: 4, Informative

    Firstly, he's not bitching about it. To quote TFA:

    But Is It Really Worth It?
    For a variety of reasons: cost, that "green" feeling, and the idea that I have an asset that generates income on my roof, I personally think it's worth it. Overall, the system has been operating smoothly.

    Secondly, if you look at the article he wrote when the system was installed, you'll see that he looked into a variety of options and chose the one that he felt fitted his situation best. It is estimated to pay for itself within 10 years, which seems perfectly sensible to me - as he points out, he's pumping money into an asset that increases the value of his house rather than simply giving it away to the electrical company.

    I don't see how it's half-assed, it's working perfectly well, it appears cost-effective so far and he says he's happy with it. You don't seem to be trolling, I don't think, but your post just fails to make sense.

  6. Shh... by conureman · · Score: 5, Informative

    Don't tell anyone, but there's a tab on the first page that's labeled "print". I don't get to wait for ads and pictures to load, but it has the text.

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    The cost of that cleanup, of course, will be borne by taxpayers, not industry.
  7. It Will Pay Off in 9 Years by Doc+Ruby · · Score: 4, Informative

    That article has a lot of consumption and billing numbers for each of utility and homegrown power, but it's hard to get exact performance comparisons because the numbers don't exactly measure the same things. There is no exact start and end date, just month names, and approximate mentions of offsets into them, not lining up generation and billing dates in either the solar generation half-year or the time before drawing from only the utility. And practically no data on income from overgenerating, selling back to utility or grid.

    But there is enough data to make rough comparisons. They say their January/utility bill was $446, but their December bills are the highest (all of which extra usage was billed in the highest rate, 300% of the base rate). So let's say their average bill used to be $450:mo, or $5600 annually. However, they said up front that their annual bill is about $4400. We'll take the average of $5400. Now their July-December/solar bill is $389.39. Even if we call that $400, and so their annual/solar bill is $800, they're saving $4600 a year. They paid about $55,000 before rebates, about $37,000 after all rebates. Their utility bill savings pays off their installation investment in $37,000 / $4600 = 8.04 years. Pessimistically, they should be paid off in 9 years.

    These systems have a minimum lifetime of 30 years (if you don't invest in an upgrade during that time). Even if energy rates stay the same in those 30 years (probably not, probably higher), that $4600 for 21 more years is $96,600, or 2.6x the installation cost. Total return is $133,600 on $37,000 investment, so 3600% Return on Investment over 30 years. If you invested that money in a compound interest account (either savings or some investment with an average annual return reinvested), you'd have to get 15.43% annual compound interest to turn $37K into $136K in 30 years. Conversely, if you took out a 30 year mortgage on your home at today's average rate of 5.63%, you'd net 9.8% benefit. Which means that it's worth mortgaging (part of) your home to invest in these, with a fraction of your old utility bills paid as mortgage interest, and getting $78K more ("profit", really utilities savings) after 30 years, with no out of pocket.

    That could be even better than they say. Their reasons for failing to maximize their roof generating area don't seem compelling: "it would get a little crowded up there". Other than access to the panels for cleaning, who cares how crowded it is? It looks like they could double their area. Which would give them closer to zero Winter bills, but overkill in Summer that exceeds what's left (if any) during Winter, which exceeds their "zero annual bill" maximum for reselling overgeneration to the utility at retail rates. So probably about 1.5x the area would give them Summer overgeneration that would equal their Winter utility draw, netting zero bills. It's got to cost less than 1.5x to install just more area, because labor and shared components (especially the inverter that sells power back to the utility) are a substantial cost that doesn't increase at all at that rate. Say it costs 1.2x, or $44,400, but they save the full $5400 annually. That's still about the same time in payback (about 2% longer), but 3.7x the return. And the "green feeling" is complete.

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    make install -not war