Arco Photovoltaic Solar Power Plant
March 29, 2009 – 4:55 pm 
September 10, 1987
San Luis Obispo County used to be home of the world’s largest solar-cell power station.
Built by an oil company in 1983, the view of the Arco solar power plant was an eerie combination of age-old scenes of sheep grazing and science fiction technology.
Every few minutes the silence of the Carrizo Plains would be broken with the whir of 799 solar arrays following the sun. The plant could generate 6.5 megawatts.
For comparison the Diablo Canyon Nuclear Power Plant generates 1,073 megawatts from Unit 1 and 1,087 MW from Unit 2.Four natural gas fired units at the aging Morro Bay Power Plant can generate up to 1002 megawatts but rarely do. The antiquated 1950’s era technology is not cost effective.
The solar plant was a product of government incentives created in the wake of the 1973 oil crisis.
The sudden interest in energy independence had unintended benefits.
A major reason the Soviet Union could not keep pace with President Ronald Reagan’s military build up was that the oil market collapsed as America cut oil consumption. No demand for Russian oil, the ruble falls, no budget.
When oil prices fell the U.S. lost interest in energy policy. Reagan removed solar panels from the roof of the White House and allowed tax credits to dry up for alternative energy.
Now Russia uses fuel as a foreign policy weapon.
Nations like Germany have taken the lead in solar development.
By April 1995 the last of the Carrizo solar panels were being scrapped. Now the wind whistles through a cyclone fence enclosing an empty field.
Today after another oil price spike there are proposals for three new solar plants on the Carrizo north of the Monument.
Photos by David Middlecamp
16 Responses to “Arco Photovoltaic Solar Power Plant”
Dave,
Who operated the plant?
By Nick on Mar 29, 2009
I have read that the newer photo-electric panels are 200 to 300 percent more efficient (produces 2 to 3 times more electricity per square footage) than those old style 1980’s versions used as listed here. So, therefore, such a farm as wide and long as the previous one could generate a full 18 – 21 MW! And its all FREE!!! Sort of.
By Steven Lester on Mar 30, 2009
Thanks for the comments Nick and Steve.
Arco operated the plant for a number of years but they sold it when the tax credits dried up.
Later solar plant owners tried to negotiate a higher rate before the Public Utilities Commission but PG&E argued that the rate payers did not want more expensive power. The plant could not pay for itself and was dismantled.
Before someone launches a ‘free market wins’ comment keep in mind that the U.S. tax payers subsidize oil, gas, nuclear power and ethanol.
PG&E had no qualms flipping the rate payer argument, and winning, when the utility negotiated to be paid higher rates for Diablo Canyon power than they paid for Carrizo Solar.
Nuclear power has helped keep tons of green house gasses out of the atmosphere.Environmental costs need to be factored into our future power development choices.
I’d be curious to know how many tons of carbon dioxide Morro Bay, Diablo Canyon or Arco Solar would have saved or produced over the last 10 years at full operation.
By David Middlecamp on Mar 30, 2009
When the wind picked up on the Carrizo, as it usually did every day, the panel arrays would make all sorts of whistles and moans as the winds whirled among them.
The arrays also collected many tons of tumble weed too. We were hunting rabbit nearby, when the arrays turned to the sun…..scared the poop out of us
By SSG David Medzyk on Mar 30, 2009
I had no idea there was a precedent for putting solar panels on the Carrizo Plains. Thanks for digging this up.
By Sarah on Mar 30, 2009
I did some maintenance work at the facility. They were using electric carts around the facility for some of the personnel. They had mounted 4′by 8′ solar panels on the roof of the carts to charge the batteries. The biggest problem they were having was overcharging the batteries. The electronic devices they were using to regulate charge rates were not adequate.
By Dave on Mar 30, 2009
I have a question for any who know this plant or worked on it. How much water did they use? How long was the well pumped that was located on the property? Thank you for your help.
By Gena on Apr 12, 2009
To my knowledge there was no water needed. There is another part to this story, however. Mirrors used to concentrate light and increase output on the solar panels generated heat, turning the laminate brown and degrading the PV output. I’m surprised that it is difficult to find a mention of this.
By tony woicekowski on Apr 29, 2009
My understanding was they also had to wash the mirror and solar cell surfaces to keep the dust off. A very labor intensive process. I look at the new designs and still have not seen a fix for this dust problem.
By ray on Jun 23, 2009
Hi. This question goes to Dave. I have a keen interest to understand what exactly the mirrors were made of for that Arco solar project. Since you worked on it, would you mind commenting on this? Were they back-silvered glass? Or some kind of metalized film mirror, or what?
Thanks
By David W on Jul 1, 2009
As I understood it the mirrors were tacked on after the original design in a bootstrap effort to boost the output, with the problems that Tony W mentions. My guess is they were garden variety mirrors from a glass shop.
By David Middlecamp on Jul 5, 2009
I had not heard that the mirrors were an after thought. In looking at the plant layout and the tracker design, it seems unlikely to me that would be the case. My understanding was that the “browning” would accelerate and further degrade the laminate. Once removed from the mirror concentrators, the browning stopped. My experience with these panels confirms that. In any event, the giant mirrors were sold off. I believe that Zomeworks in Albuquerque NM had some involvement in the dismantling, perhaps as an investor or project manager.
By tony woicekowski on Jul 18, 2009
I was involved in the dismantling of the solar plant in late 1994. My gandfather built the plant. The story that I was told was that after it was no longer profitable it was sold for 1/10 the cost to build. We took down the large panels and dismanteled them into individual panels, tested, repaired and resold them. As of the last time I was in the area the fenced 160 ace lot was still there. I also understand that the dismanteling company was only required to leave the property flat and level. If this is true, there is hundreds of feet of 5 inch copper cabel still underground. I often wonder if anybody has gone back and dug up the cable? Oh, side note, besides the dust and tumble weeds theyhad a bird problem. We had fun shooting the boom cannon to scare them away. Don’t remember much else except that I wish now I would have bought some of those panels.
By bob lonergan on Aug 1, 2009
I am an electrician I was there in the beginning until almost the end of construction. Sad to see it all torn down.
By Ginger Hume on Aug 28, 2009
Solar Power is so cool. it is clean and renewable energy. when the cost of solar panels goes down, i think every home should be owning a mini solar power station.
By Detox John on Oct 2, 2009