Detroit Rocks for Solar Power Incentives Too

Susan Kraemer

Wow, couldn’t happen to a more deserving city/state. Detroit really paid hard for the hard landing at the end of the age of fossil-fueled behemoths. Detroiters had no power over the Big Three to make autos efficient.

One suggestion, Solar Fred: instead of saying rebates are $2.40 a watt, call it $2,400 a kilowatt, because then people understand it better as a serious chunk of the thousands that they will spend on the solar system. Also, because, from my experience, people get confused with monthly tariff payments when it’s just a dollar or two. The rebate is a lump sum upfront. And it comes to thousands.

[...] Like all Americans, Detroit homeowners would get the new 30% tax credit, which would reduce cost another $6,900, leaving an out-of-pocket cost of just $6,000, according to calculations by Solar Fred at Solar Power Rocks. [...]

Dan Hahn

Great suggestions Susan, thanks!

NonScalable

If that production incentive can stay in-place for 10 years then that last $6000 is paid off. That leaves some 15 to 20 years of free electricity for the investment cost of a battery bank and charge contoller.
More than likely the production incentive will go up as fuel increases in price; that means the power company (over the next 10 years) may turn into a ‘network maintainer’ more like an IT industry rather than electricity supplier.

ECD Fan

Solar works great in cold weather, but it works horribly under snow and produces 1000 kWh/kW a year at best in locations such as Detroit (for comparison, solar can get to 1700 kWh/kW in Arizona). So, add another wasteful spending to the long-suffering Michigan ratepayer/taxpayer!

Tor a.k.a. "Solar Fred"

ECD, don’t know where you get your figures from, but we got ours from a fairly reliable solar software that estimates an average of 462.5 kWh produced per month (5550/year) for a 5kW DC STC system in Detroit. We believe this software is based on PV Watts, the clunky but industry standard created by the NREL. Because this solar software is well respected in the solar industry, we’re going to stand by those figures.

ECD Fan

To Solar Fred:

The default PVWatts assumes a derating factor of just 0.95 for snow/soiling. If you read the documentation, you will learn that 0.95 is not realistic for the Great Lakes Area and other snow-inflicted areas. Here is what NREL says about about Minnesota, for example: “Snow remains the longest when sub-freezing temperatures prevail, small PV array tilt angles prevent snow from sliding off, the PV array is closely integrated into the roof, and the roof or other structure in the vicinity facilitates snow drifting onto the PV modules. For a roof-mounted PV system in Minnesota with a tilt angle of 23 degrees, snow was observed to reduce the energy production during the winter by 70%; a nearby roof-mounted PV system with a tilt angle of 40 degrees experienced a 40% reduction.”

The fact is, the 31.2KW crystalline PV system at the Great Lakes Science Center (
http://www.glsc.org/energy/renewable.php ) delivered just 16,475 kWh in 2009 and 22,355 kWh in 2008, or 528 kWh/kW and 717 kWh/Kw, respectively (according to fatspaniel). A rooftop a-Si installation at Rochester, MI ( http://www.oakland.edu/solar ) delivered about 900 kWh/kW per year for a few years before it died last year (according to the homegrown remote monitoring system). As you see, the real world agrees with my “1000 kWh/kW a year, at best.”

Relying on calculators, especially without understanding the assumptions embedded in them, is a sure way to poor investments and financial ruin.

Tor a.k.a. "Solar Fred"

Even considering all of your assumptions are correct, ECD Fan, and I’m not saying they’re not, a $2400/kW rebate ain’t chump change, so you will get a significant up front rebate, PLUS whatever you can get out of the 11 cents/kWH production credit, PLUS the 30% tax credit AND any tax write-off from the mortgage loan. Oh, yeah. And the solar portion of your electricity needs costs you nothing beyond the loan payment.

And don’t forget that winter is only a quarter of the year! So yeah, there are going to be snow days, but don’t forget spring, summer, and fall to account for that 4.2 hours of average sunlight. That’s a real assumption too. The seasons, I mean. On the other hand, if you want to keep paying higher and higher coal-fired electric rates over the next 25 years and kick the environment in the ass at the same time, that’s your choice.

Bottom line, Solar is a great investment in Detroit and perhaps the rest of Michigan if the experimental Feed-in-tariff becomes a regular program. Far, far from being a sure way to financial ruin. Enough said.