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Switching To Solar Power — Six Months Later 591

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."
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Switching To Solar Power — Six Months Later

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  • $400 a month? (Score:5, Interesting)

    by Gothmolly ( 148874 ) on Wednesday January 14, 2009 @11:19AM (#26448781)

    Who the hell uses that much electric power?

  • by itsybitsy ( 149808 ) * on Wednesday January 14, 2009 @11:29AM (#26448957)

    Not only are you saving a lot by generating your own power (actually I'd like to see your annual generated power curve along side your savings from the years previous and the savings assuming you didn't have the solar panels installed) but you could still add panels to your roof to generate more power. I wonder what the break even point is for your system, when would more panels make sense or not? I also wonder if adjustments to your system to track the sun angle even in one dimension by lifting the panels with a motion system would be? What about adding solar water heating to your house?

  • Re:$400 a month? (Score:5, Interesting)

    by je ne sais quoi ( 987177 ) on Wednesday January 14, 2009 @11:31AM (#26448985)
    Look at the kWh, he's using 1,635kWh per month. While it is high, it's not surprising if his house is especially large and he has a heat-pump. Those things are notoriously inefficient if the temperature drops below 40 degrees F. It getting that cold should be rare in silicon valley, but it does happen.

    What I found interesting was that, while December was bad for solar power, he says:

    My total power consumption cost for the last six months is $389.39--less than my utility bill for January, 2008.

    Basically, his solar power does what it's supposed to more often than not. But then again, we've always known that about solar power, the big problem with solar is the large up-front capital cost of installing it.

    (Or other strange things, like my mother just moved into a retirement community and her housing rules say solar panels are not allowed because they're unsightly, but directTV antennas and satellite dishes are just fine. One must have priorities I suppose. Television is obviously more important than renewable energy.)

  • ROI? (Score:3, Interesting)

    by RyanSpade ( 820527 ) on Wednesday January 14, 2009 @11:32AM (#26449005) Homepage

    Why didn't this follow up article include a Return on Investment number? It would be nice if he would have included the cost of the install and compare it to the difference in his electric bills. I'm curious to see how long it will take the install to pay for itself.

  • Insightful (Score:3, Interesting)

    by Kupfernigk ( 1190345 ) on Wednesday January 14, 2009 @11:36AM (#26449091)
    Yes, he spent $36000 up front on the system, which means that even with 25 year life on the panels an eventual payback is uncertain. He must surely also know that in a few years those same panels will probably cost no more than half that, so he has heavy depreciation to contend with. Of course people do waste money on big toys- I plead guilty myself - but you don't get much actual enjoyment out of a solar panel.

    I don't know about the position in the US, but in Europe there is a market in energy efficient appliances, and a small change in cost for things like freezers can buy one with half the power consumption. It would be interesting to know if he did the exercise you suggest, and if so did a cost benefit analysis. After all, in Northern CA it might be that he is using air con which could be avoided by improved ventilation, planting, modifications to windows etc., or electric heating for part of the winter which could have been replaced more efficiently with roof thermal absorbers rather than PV.

  • by RichMan ( 8097 ) on Wednesday January 14, 2009 @11:36AM (#26449097)

    Who ever installed the panels mounted them directly flat on the roof. That is bad.

    They need to be angled for the best sun during the time the power need is greatest. Ideally they would be adjustable semi-annually/quarterly/monthly for the best angle. And if fixed would be biased toward the point of worst number of sun days and power need.

    Doing a suboptimal installation and not accounting for sun angle is not a good installation and should be perform at a fraction of potential output.

  • Re:$400 a month? (Score:4, Interesting)

    by SBrach ( 1073190 ) on Wednesday January 14, 2009 @11:37AM (#26449111)
    Anyone in the southwest running a 3-6 ton heatpump in the summer when it is over 100F and the winter when it is below 40F. My house is 1400 sq. ft. and even though I have one of the cheapest electricity rates in the country (APS combined advantage 7am-12pm)I still pay $250-350/mo. during the summer. So far my bills for Nov. and Dec. have only been around $150/mo but I also have a load controller on my house which many people say cuts their bills in half. Basically I set a maximum demand limit in kW's and the unit prevents either my A/C, dryer, and/or hot water heater from running if need be to stay under that limit depending on the priority set for each appliance. Currently I have it set at 2.0kW but during the summer it needs to be above 5.5 for the A/C to run enough to keep the house cool. The unit does not restrict anything during off peak hours.
  • Re:$400 a month? (Score:5, Interesting)

    by jellomizer ( 103300 ) on Wednesday January 14, 2009 @11:38AM (#26449129)

    My January bill was $170.00 for Upstate NY That was for electric and Gas, in a building over 100 years old. That is Not in any way energy-star complaint.

  • Re:$400 a month? (Score:5, Interesting)

    by Andy Dodd ( 701 ) <> on Wednesday January 14, 2009 @11:54AM (#26449425) Homepage

    "but directTV antennas and satellite dishes are just fine"

    After a couple of legal battles, there are some federal laws that say that banning antennas and dishes in a housing development is not permitted. Many developments try to do it anyway but you can fight it if you know the right laws.

  • Re:$400 a month? (Score:5, Interesting)

    by drunkennewfiemidget ( 712572 ) on Wednesday January 14, 2009 @11:54AM (#26449439) Homepage

    I live in Canada. The weather today is -25c or so. My power bill never exceeds $46/CAD a month when I have a window AC unit going in the summer, and my gas bill never exceeds $70/mo.

    The # of kWh/mo he's using would suggest to me he'd be a lot better served putting the time and energy into replacing bulbs with CFLs, turning off computers that don't need to be on, and buying higher efficiency appliances rather than those solar panels. .. or both, of course.

  • Re:$400 a month? (Score:5, Interesting)

    by Joe Snipe ( 224958 ) on Wednesday January 14, 2009 @11:55AM (#26449459) Homepage Journal

    Dishes are allowed because someone paid the FCC to enforce the right to install one. If you can come up with a solar panel that generates ad based revenues and is steeped with kickbacks and non-compete contracts, someone will pay the FCC to enforce the right to install those on your moms roof too.

  • Re:$400 a month? (Score:3, Interesting)

    by scorp1us ( 235526 ) on Wednesday January 14, 2009 @11:57AM (#26449503) Journal

    The objections of the world are just that. They are in shacks, eating raw organic foods (if any at all).

    The US's energy consumption per capita is through the roof. There is an idea that there has to be curve of diminishing returns where your energy use to work and sleep in a house tops out.

    I don't know what Mr. Gore is running to produce a bill like that. It is obscene, even for an American.

  • Re:$400 a month? (Score:3, Interesting)

    by liquidpele ( 663430 ) on Wednesday January 14, 2009 @11:57AM (#26449515) Journal
    The efficiency of your appliances comes into account a lot. I once had a $400 bill in an *2 bedroom apartment* the on the ground floor because the AC unit they had was just that horrible. Then we had a crackhead kick in our door and steal shit so we moved ;)
  • Re:$400 a month? (Score:5, Interesting)

    by MBGMorden ( 803437 ) on Wednesday January 14, 2009 @11:57AM (#26449517)

    It's not just being paid off - external television antennas were part of those laws too.

    The whole thing is disgusting to me though. We're not living in any semblance of a free country when your neighbors can tell you what things you can and can't have on your property simply because they don't look pretty.

  • by clonan ( 64380 ) on Wednesday January 14, 2009 @11:57AM (#26449519)

    I went back to his original article (the instalation). He said the estimate is that his anual utility bill will drop from 4400 a year to 1100 a year.

    So I made a few assumptions.

    #1-his power use will not increase. Not really likely but a future increase shouldn't change the ROI on his current investment.

    #2-Utilities will just keep pace with inflation (assumed 2%)...power costs will stay porportinally expensive in the future. This is probably not ture as power prices tend to increase slightly faster than inflation. So this assumption will tend to increase the ROI.

    #3-I assume he is financing it through his mortgage at about 5%

    Therefore when I calculate out to 25 years I find that he would spend about $141,000 in power over the 25 years without slar. With Solar he would spend $35,233.

    The Payoff date comes at about 12.5 years.

  • Re:$400 a month? (Score:3, Interesting)

    by d3ac0n ( 715594 ) on Wednesday January 14, 2009 @12:35PM (#26450251)

    An article based around a single one-year competition on a year that had lower than average rainfall does not a weather trend make. While Buffalo is certainly no London England, we do get our share of cloudy days. Average rainfall in Buffalo NY is between 38 and 40.50 inches. 2007 had around 30 inches. A drier than normal year, although not the driest. 2008 was much wetter, right near 40 inches, with many more cloudy days than 2007.

    Notably, nobody here on /. seems to have thought about SNOW or TREES. Buffalo is known as the "City of trees" for a good reason. We are an arborist's wet dream around here. I personally have a VERY large Sycamore within 10 feet of the rear of my house. Because Sycamore's are rather rare I'm loath to cut it down, but it's actually causing moss to grow on several areas of my roof due to the large amount of shade. Although we had an arborist trim it back a bit, which should help this coming summer. I won't even get into the bark shedding that Sycamores do.

    Of course, there is always snow to contend with. I don't know about you all, but I'm not about to climb up a 20 foot aluminum ladder in the winter to clean the snow off solar panels on the roof of my two-story home. I LIKE being alive, and the idea of being found dead in a snow drift with a broken neck from slipping off a ladder while sweeping off solar panels is not particularly appealing to me.

    The point is, while solar panels might help a little, the high initial investment cost plus high (and potentially dangerous) maintenance they would need in a northern climate makes them practically worthless, if not literally so. I want to save money as much as the next person, but Solar ain't gonna cut it for me or pretty much anybody in my region. We need another option, and I don't see any. Which really sucks.

  • Re:$400 a month? (Score:5, Interesting)

    by mcvos ( 645701 ) on Wednesday January 14, 2009 @01:09PM (#26451045)

    The house is less than 2 years old so it should be decently insulated though the windows are only single paned.

    So it's not.

    Exactly. I'm amazed to read that some new houses in the US are so badly insulated that they have single paned windows. In Netherland people stopped doing that in the '60s or '70s.

    Mind you, my previous house was from 1913, and before it got renovated, it had single paned stained glass windows, with wind blowing through gaps around them. Impossible to heat, so in winter I wore an extra sweater and lived next to the heater.

    After it got proper insulation (including ugly windows, unfortunately), I hardly even needed the heater in winter. Good insulation matters a lot.

  • No single solution (Score:3, Interesting)

    by AviLazar ( 741826 ) on Wednesday January 14, 2009 @01:25PM (#26451415) Journal
    People talk about single solutions but that is not the answer. It will be a blended solution. It will be a combination of solar, natural gas, wind, water, AND nuclear. In Israel, ever since I can remember (80s) each house/condo has solar panels to help heat water tanks...which are also sitting under the sun. Wind turbines are in various areas (Atlantic City NJ has about 5 or 6 MAJOR wind mills). Water turbines can work well. In California they created these water turbines that are hidden into the cliffsides. So when surf hits it water is sent up (and back down) to generate electricity.

    But all of those will not be enough. We also need to supplant that with natural gas and nuclear energy. We also need to find ways to recycle spent nuclear fuel and convert it to useful energy...put it this way if that spent fuel is SO radioactive (meaning having lots of energy) then we could harnass it - we just don't know how (i think).

    Until we get warp power - a blended solution will be needed - but it can work.
  • Re:$400 a month? (Score:4, Interesting)

    by MrSteve007 ( 1000823 ) on Wednesday January 14, 2009 @01:27PM (#26451479)
    A couple points.

    1. At that latitude, the angle you mount your panels for operation would be steep enough for most snow to slide off. Also the dark color of the panels means that the snow will melt off there first. Although the snow may eventually build up at the base and block the rest from sliding off.

    2. Amount of Sun. It's all about the solar insolation measurement. The feds have been logging this data for 30+ years and averaged the amount of annual sunlight in several areas in each state. []

    The above link is a good chart for this. The average for cities in New York is about 3.5, which equates to right around 3.5 kWh daily output for each installed 1,000 watts of generation capacity. That isn't the best, but it still is plenty. Germany has the largest number of installed PV arrays, and they are just as, is not more cloudy than New York.

    I operate a 10 kw solar PV array in perpetually cloudly Seattle. We're going to see a payback of right around 10 years. Solar works just fine for us, although we do expect greatly reduced output in the winter months. The longer days during the summer, due to the high latitude, helps make up for some of that though. [] My array.

  • by ducomputergeek ( 595742 ) on Wednesday January 14, 2009 @01:51PM (#26451997)

    And that's in the winter. It's a lot more in the summer because of AC. Granted our building faces south and in the winter time gets a lot of solar time when the sun is out.
    Granted we're a business and we run several servers in house 24x7 for development, testing, and backup and about 25 PC's.

    We put up as much solar as we could given our amount of roof space last October. We've seen our electric bill go down to around $700 - $900 per month. It's basically cut our bill in half. Now we had the cash on hand to invest in the technology, plus there were some tax write offs that made it advantageous to do so before December of 2008.

    But we viewed it as a wise investment that freed up over $1000 a month in cash flow. That's about a $1000 per month we can spend on additional development. It doesn't sound like much, but it was enough to offer 2 paid internships this spring semester at the local university.

    Will the investment still take 5 - 7 years to pay for itself? In raw dollars, yes. But there are intangibles as far as I'm concerned. We've found two really good interns for this spring semester. Just over winter break they were able to take a piece of one project and get it to a working beta. It was the final piece of the puzzle to finishing that product that is now on the market and we've already got 20 installs lined up totaling about 1/3rd the cost of the solar panels.

    Granted, we knew what our limits were. We did it not to be green and save money. The cash was either going to be given out as dividends (we are employee owned) and taxed or retained as earnings and taxed.

  • Re:$400 a month? (Score:3, Interesting)

    by FishWithAHammer ( 957772 ) on Wednesday January 14, 2009 @02:31PM (#26452707)

    Please don't conflate "conservative" with "neoconservative". I am the former; "conservatives = Republicans" is the latter.

    I wrote in "None of the Above" on my Presidential ballot because I couldn't in good conscience vote for either Presidential candidate, voted Republican for my senator (because her Democrat challenger proved very incompetent in the House), and voted for a Democrat for the House of Representatives because her Republican challenger is a moron.

    I dislike Gore for his hypocrisy, not because of his party affiliation.

  • by Doc Ruby ( 173196 ) on Wednesday January 14, 2009 @03:40PM (#26453907) Homepage Journal

    You're right about the future value / interest calculation. I mistakenly used the paydown for a $37K 30 year mortgage to cost $136K in interest. The proper calculation [] shows that $37K would earn about $136K over 30 years at only 4.43% annual compound interest. Which is a little lower than the low mortgage rates today, so financing it with a mortgage is a net loss, but not a big one, with no (annual) cash flow impact. Better than leaving that equity in the home not working for you.

    But the real investment of $58K (according to the article, not $55K) gets about $21K subsidies repaid within a year or so, atop the energy savings. Yes, various people in large amounts have to pay those subsidies (tax rebates, etc), but they are paid. If everyone were just directly buying unsubsidized systems like this one, the economy of scale (and increased R&D improving operating ROI) would probably at least equal the 31% subsidy. The purpose of the subsidies is to jumpstart the massification of the industry. That's how we get the "green feeling" before we're fully green.

  • by MrSteve007 ( 1000823 ) on Wednesday January 14, 2009 @06:50PM (#26457153)
    Our building's insurance didn't increase after the installation, as its included by the insurance agency as 'equipment', just the same as the heating and cooling system. It didn't change the property tax for us at all, since the facility is already worth a few million, and land values have been going down in the area.

    Annual maintenance costs for us have just been an hour or two of squeegeeing every 6 months. Other than that, it just hums along next to silently every day. The furnaces at the building require more maintenance.
  • Basically, you're right that consumption reduction isn't a necessary part of this story. Loyd simply wanted to take advantage of the freely available thermonuclear energy stream we get from the sun every day. But cutting his consumption of energy from the utility company is a key motivation here. By reducing his overall energy consumption, he will increase the percentage of his energy usage that is funded by his solar installation, reducing his dependency on the grid.

    As someone who has also experimented with a solar installation over the past 6 months, I can attest that a funny thing happens regarding your attitude towards energy consumption when you start getting some of your energy from the sun: It makes you hyper-aware of your overall energy consumption and much more aggressive in saving energy wherever you can.

    My solar installation is micro-scale compared to the Loyd's: I started out with one PV panel hooked up to one deep-cycle battery off of which I ran an inverter to power handful of small devices in my office running on AC adapters (modem, router, phone chargers, etc.). The whole thing was under $500.

    While my initial motivation was like Loyd's (supplement my energy sources), my little experiment has made me extremely protective of the energy I get from the sun; I don't want to run any devices more than necessary lest I drain my battery, to maximize the solar-based energy. As a consequence, I'm much more aware of which devices really need to be on or off and which are energy hogs. I'm also more conscious of energy drains that aren't hooked up to my panel (lights) as well as non-electricity based energy (central heating).

    End result: My Dec 2008 monthly energy bill was $200 lower than Dec 2007. I can attribute only a fraction of these savings to the energy I get from my micro-solar set up. The bulk of it came from the energy consumption awareness imparted by having a solar installation.

    Btw, I intend to write up the details of my do-it-yourself micro-solar home installation. Keep an eye on [] if you're interested. (I just updated DNS for this domain, so it may take a few hours/days to resolve.)

  • by niktemadur ( 793971 ) on Wednesday January 14, 2009 @07:34PM (#26457943)

    I remember reading about solar shingles a few years ago, how it was supposed to be the next wave of solar power for the home, the price was lower for installation, etc. I did read that they were a bit less efficient, but you were able to cover a much larger area of your roof for the price, thereby more than offsetting the disadvantages.

    Fast forward to today, everywhere I look people are still installing solar panels and I haven't seen a single new article, blog or discussion about solar shingles. Was the technology flawed?

    I'd love some feedback on this, because there's a possibility I might build a home in the foreseeable future, and I'm definitely intending on going solar for both electricity and water, maybe even a heat pump. Proper insulation is a given, energy efficiency appliances, passive solar design. I'd love to shoot the works on this project.

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