Cheap(ish) DIY Solar Power is a Reality

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I just stumbled across a story on CNN’s website from a couple of weeks back about SpinRay Energy, and its do-it-yourself, modular, plug-and-play DeckPower 120 solar panels.

The company is selling–not promising, not developing, but actually selling–solar panels that you can install yourself, one-at-a-time if you’re on a tight budget, and plug into an external mains outlet to supplement the energy you’re receiving from your local power utility. Up to five panels can be installed, and with all five in place, the system generates up to 1000 watts of energy. For every hour that all five panels receive direct sunlight, that’s up to 1kWh of power that you’re not paying the electric company for.

And since the system merely plugs into an outlet–thanks to a small, cellular-phone sized microinverter that converts DC into AC–it’s considered an appliance, and therefore not subject to special permits, and don’t require an electrician to install.

The panels are selling now for $999 apiece, and I did some quick back-of-the-napkin calculations to figure out how much energy–and how much money–that would save me in the long run. I won’t bore you with all the numbers, but with five panels in place on the west side of my patio cover, I would save about a buck a day, and the panels would pay for themselves in about fourteen years (or about 9.5 years if the 30% federal tax credit applies. It seems that it does).

I have to admit, in my area of Alabama, all of our power comes from relatively clean (at least in terms of impact on the global environment) hydroelectric power, so I’m not champing at the bit to drop $5000 on the system, but it’s conceptually exciting, nonetheless. Modular, plug-and-play, DIY solar energy, on the market now… who would’ve thunk it?

The company offers a 5-Year limited warranty on material and workmanship and a 12-Year and 25-Year limited warranty on minimum power output, but, of course, solar companies come and go quite a bit as of late, so there’s no guarantee that SpinRay will be around long enough to honor that warranty.

And there are a few other caveats worth noting: firstly, if the power goes out, the panels shut down, so as not to endanger line workers fixing the outage. Secondly, professional installers aren’t digging this concept one bit, for a number of reasons, so although the DeckPower 120 is considered an appliance and is free from regulation for now, there could be some backlash.

But still, this is a proof-of-concept product that all of us who trumpet green energy should be excited about. Head over to the original story for more info.

Via: [CNN]

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  • tahrey

    A 15-year best-case return on investment? The price of entry may be a bit lower than the typical multi-kilowatt full-roof installation, but the actual price-per-watt is considerably higher. The professionally installed systems on the market right now (which, at least in my area, can be had more cheaply with government grants, or installed at low cost/for free on the understanding that the company gets a cut of or even all of your grid feed-in refund, and you simply benefit from not paying as much of a bill for supply), when actually paid for, offer more like a 10 to 12 year ROI.

    Which is still too much for me. Once it comes down below five figures for a typical setup, and an 8-year ROI (preferably 5, but that may take some time to come to fruition, long enough that it makes more sense to go for 8-ish), then we’ll talk more seriously.

    There’s just so many other things you could do with the money to give a better payback over 15 years (bearing in mind that, until those 15 years have passed, *you’re still out of pocket* … IE the panels won’t actually have *saved* you any money for A DECADE AND A HALF … and their typical lifespan is only about 25 years) that it just doesn’t make any kind of sense to bother with it, unless you fancy being an off-the-grid early adopter and will in fact hook them up to storage batteries and use the bare minimum of electrical power to avoid draining those batteries for the average 16 hours a day that the panels aren’t making a decent amount of power (and average 12+ they’re making none at all).

    And that’s without even considering the effects of bad weather. During a rainy day last week, around midday, I had a look at the energy meter hooked up to a large bank of photovoltaics that have recently been installed on the roof of an outbuilding at work (total floor/flat roof space, oh, maybe 1000sqft, and 33-50% coverage, south facing?)… they were cranking out all of 700 watts. My baseline consumption for the various always-on devices in my apartment is more than a third of that… if my part of the roof was entirely covered with cells, and no-one on the lower floors was sharing, I still would only have broken even on that day without even turning on a light, watching TV, cooking anything, or washing.

    I suppose Alabama almost certainly has more average hours of sunlight and typically better weather than the UK, so perhaps you’ve made allowances for that… but still… think about the other, cheaper things you could do that will save more than $1000 over 15 years…

  • tahrey

    (I mean … $999 divided by 15 … that’s $333 divided by 5 … or $67 a year, AFTER it’s finally paid for itself (quite how you reckoned “a buck a day”… unless that was for the 5-panel, $4995 setup? So, $333 a year?).

    Chicken feed. There are endless savings accounts you can put that money into which will give a better return than that with compounding (if you stuck the money in a mattress for 15 years THEN put it in the account)… or even if you ignore that effect (if you put the money into a 15 year bond straight away).

    Hell, just use it to pay your mortgage down a little more, if you have one.

    Doubling your money over 15 years would require a savings account or bond with a 4.73% annual rate of return, after tax. Doubling it over 30 years would require a much more modest 2.3%, which is really rather low for any kind of long term savings account. My mortgage interest rate is most certainly closer to the former figure than the latter. Shoving a grand (or five) towards it in early repayments would make me considerably richer as I headed towards retirement than buying cheap, poorly installed (as I would be installing them myself!) solar cells.

    Oh, and brilliant how the guarantee only extends to 5 years in terms of outright failure, eh…

    And … OK … let’s be fair … let’s assume it’s a 9.5 year payback period, and that the cells are somehow still working at 100% efficacy after almost 2 decades of probably almost nonexistent maintenance, so you’ve got your investment amount back on top of breaking even after 19 years.

    200% to inverse power of 9.5 is… 7.57% annual return. That’s what it would take for a 10-year bond to double your money in about the same time it would take the panels simply to pay for themselves.

    200% to inverse power of 19 is… 3.72%. So with the subsidy, clear skies and a following wind (and, I suppose, assuming no massive changes in per-kWh electricity bills, either up or down), that’s how good a guaranteed annual return, after tax, a savings account (or what the interest rate on a mortgage you paid down with the $1000~5000) would have to offer to match the good the panels could do for you over almost two decades.

    (Let’s make it 25 years … a typical mortgage term … per-panel, clearing $999 in 9.5 years (or doing the equivalent of it) means ~$105 per year. So after 25 years, the panel will have generated $2629 worth of electricity, or $1630 of profit; 263% of what you put in at the start. If your mortgage interest rate is 3.9% or greater, and likely to stay that way, you’re better off shoving the money into that. Not least because you’ll still be paying it off at the same rate afterwards, but will be several months or even a year ahead of the game having both paid off more of the capital, and ensuring that you’ll pay less interest overall, and once it’s entirely paid off you’ll suddenly have several hundred, if not a thousand-plus dollars extra to play with each month…)