Washington Utility Proves Home Solar and Wind Too Pricey?

February 4th, 2011 by Susan Kraemer

The Northwestern plains are widely considered to have the best conditions for wind power in the US. But a fourteen month pilot project at Inland Power and Light, in Spokane, Washington, set up to compare solar and wind installations proved surprising. The solar panels produced about five times as much power per dollar as the wind turbines.

“Solar,” Richard Damiano, the utility’s chief engineer told the The Spokesman-Review “is trouncing wind.”

The utility set up a “bank of solar panels” and “a 35 foot wind turbine” as an experiment to show which was better, in order to help their customers decide what to install on (or near) their homes.

The experiment indicates that for a similar investment of about $23,000 in Washington state, solar produces five times as much power as wind. The solar panels produced 15% of the electricity of the average home, according to the utility. The wind turbine would produce only 3%.

However, the article does not note the actual power rating power rating of either the “bank of solar panels” or the “35 foot wind turbine.” As a result, it is impossible to check that the comparison is actually kilowatts-to-kilowatts.

But what struck me was how poorly both did. Almost unbelievable.

If the utility’s figures are accurate, after spending $23,000, less than 15% of the electricity could be supplied???

To a Californian like me these figures look unbelievably low. Our own house is producing solar at 6 cents a kilowatt hour, averaged over the 36 year life of the array. We got a SunRun PPA (power purchase agreement) at a guaranteed rate of 12 cents a kwh for 18 years including inverter replacement (and then you keep the system after that for free).

For $10,000, 80% of the electricity our house needs – 550 kwh a month – and maintenance, replacement and inverter replacement – are covered by a 3.15 KW array. (We chose to pay all 18 years of the PPA upfront, because we wanted to have no ongoing bills at all, but most people choose to spread out the PPA payments like with an utility electric bill.)

Since our solar will continue to produce free electricity after that for at least another 18 years, that averages to 6 cents a kwh, if you average the production for just a 36 year life.

I am at a loss for why their results are so different. Spokane, Washington has only half an hour less insolation a day than California. The same 30% Federal tax credit is available. Perhaps it is that California is one of nine or ten states where renewable energy companies like SunRun and SolarCity are allowed to compete with electric utilities for your business.

With such an exorbitant cost in Washington for such a miniscule fraction of the average electric bill, It would be interesting to get another pilot study, that is not run by a utility.

Image: Travelpod

SusanKraemer@Twitter

Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.

About the Author

Susan Kraemer writes at CleanTechnica, CSP-Today, PV-Insider , SmartGridUpdate, and GreenProphet. She has also been published at Ecoseed, NRDC OnEarth, MatterNetwork, Celsius, EnergyNow, and Scientific American. As a former serial entrepreneur in product design, Susan brings an innovator's perspective on inventing a carbon-constrained civilization: If necessity is the mother of invention, solving climate change is the mother of all necessities! As a lover of history and sci-fi, she enjoys chronicling the strange future we are creating in these interesting times. Follow Susan on Twitter @dotcommodity.

Anonymous

Susan, nice article…it inspired me to write one of my own where I did some analysis. I even got the utility to respond to my requests and give me the actual numbers from their tests. The reason their solar results are so far out of line from what you are seeing in your home in CA is they are basing the average electricity consumption/year at 18,000 kWh (their customers heat with electricity), where you are using about 6,600 kWh/year.

Let me know what you think!
http://blog.mapawatt.com/2011/03/27/residential-clean-energy-solar-vs-wind/
- http://cleantechnica.com/author/susan Susan Kraemer
  
  Oh, my God, what a lot of electricity! Don’t they have any insulation??? They should add solar hot water, and heat their homes with radiant heating. Or keep the electricity but feed a Steffes thermal energy storage unit, for heating using off peak power at night. That is such a waste!
MD

I live South of Spokane, near Pullman WA, we’d do quite well with solar, though in my area we have almost constant wind near the “Breaks” which is on the rim of the Snake River LC Valley, Iberdrola renewables is in our area too, they have test wind mills up. For solar, the best thing to setup in our area is a solar powered hot water system, I did an experiment with a car radiator, I was able to get it to crack in mid july, simply filled it with water, capped it and left it in the back yard on top of the shed… sure enough, gets hot enough to pop the radiator and make steam…
- http://cleantechnica.com/author/susan Susan Kraemer
  
  Cute experiment!
darth

How do you use on 550KwH per month? I avg 3x that and I have put in numerous efficiency upgrades (hvac, washer, fridge, lights, insulation) (i have a big house)

so what produces 80% for you would only produce %30 for me. I wonder what they use for their average use home?
- http://cleantechnica.com/author/susan Susan Kraemer
  
  Actually 550 kwh is the statistical average in California. It is partly the mild winters here compared to states like Minnesota with long cold winters and if they have houses with electric heating. Is that your case?
  
  But also, states like Wyoming with no building codes cost far more to heat and cool than states like California with Title 24 energy efficiency building codes requiring efficient buliding.
  
  Because of that code, our house was built with double pane windows, reflectant roof deck paint, passive solar design, very good insulation. Then recently we have gradually replaced all the incandescents with cfls, or LEDs, the washing machine and fridge are efficient.
Pingback: Washington Utility Proves Home Solar and Wind Too Pricey? – CleanTechnica : GreenEnergyGroup – Tips and Resources for using wind and solar
Bill Woods

To start with, they’re talking about the first two weeks of January, when Spokane’s solar production is less than half its annual average — ~2 vs. ~4.5 kW-h/m2/day.
http://www.nrel.gov/gis/images/map_pv_us_january_dec2008.jpg
http://www.nrel.gov/gis/images/map_pv_us_annual10km_dec2008.jpg

By contrast, for the East Bay, the figures are ~3.5 vs ~5.5 kW-h/m2/day. [Eyeballing the maps, YMMV]

Secondly, I think they’re using the real cost, not counting the federal (and Calif?) subsidies.
Pingback: Tweets that mention Washington Utility Proves Home Solar and Wind Too Pricey? – CleanTechnica: Cleantech innovation news and views -- Topsy.com
Ken Clive

Perhaps the cost of permits to put up those turbines and panels was too high? I wouldn’t be surprised if the city of Spokane opposed the construction of what they think are unsightly solar panels and wind turbines (they tend to forget that coal plants look worse lol).