Big solar, little solar

Which renewable technology holds the key for a sunnier (and more democratic) energy future?

Desert solar farms like the Ivanpah facility (above) need miles of transmission lines. Rooftop solar panels (below) don't.

At a business conference this past May hosted by Wired Magazine, Bill Gates, the billionaire chair of Microsoft and an influential philanthropist, offered his two cents on solar energy. "If you're going for cuteness," he told Wired, "the stuff in the home is the place to go. It's really kind of cool to have solar panels on your roof. But if you're really interested in the energy problem, it's those big things in the desert."

Those big things in the desert are solar farms, designed to concentrate energy from the sun using arrays of mirrors or parabolic troughs spanning vast swaths of land. They're green versions of the types of power plants big energy companies have always relied on — centralized, dependent on transmission lines, and requiring billions of dollars in investment. Some rely on water from desert aquifers for cooling, cleaning, and steam generation. Yet the plants can replace electricity that traditionally has been derived from burning coal, representing a significant advancement away from fossil fuels.

It's too early to say whether California's energy future will follow Gates' maxim that rooftop solar is "cute" while desert solar represents the serious stuff. Others have argued just the opposite, and momentum is building on both fronts. Gov. Jerry Brown has endorsed the idea of installing 12,000 megawatts of rooftop solar, and was expected to bring stakeholders together in late July to discuss how to accomplish that goal.

At the same time, large-scale desert solar is attracting billions in investment, and big-name companies such as Bechtel, Chevron, AECOM, and Pacific Gas & Electric Co. are engaged in its development. The California Energy Commission approved nine desert solar-thermal projects last year, capable of producing 4,100 megawatts.

As California moves toward fulfilling a mandate of generating 33 percent of electricity from renewable power sources by 2020, there's bound to be a political edge to solar development too. Giant utility companies profit by sending power along their transmission lines from desert solar farms to the grid. On the other hand, if energy-conscious customers generate more power than they use with rooftop solar panels, the utility company has to cut them a check. So there's little incentive for utilities to encourage customer-owned, distributed generation of renewable power.

Jeanine Cotter, CEO of San Francisco-based Luminalt, a small solar installer, says it takes her work crew about a day and a half to mount new panels onto a rooftop. "That will produce power for that home for the next several decades," Cotter notes. "It's a rapidly deployable technology that is durable and will last a long time."

Cotter practices what she preaches. "At my house, if you turn on all the appliances, you can look at the meter and see that we're still relying on PG&E to bring us power," she says. Cutting down results in the meter showing that the panels are producing electricity for the grid.

Self-empowerment is a major draw for proponents of rooftop solar. "The choice is pretty clear: pay for the ongoing cost of remote central-station renewable power or pocket the savings of locally-generated renewable power," Al Weinrub of the Sierra Club writes in a pitch for decentralized solar generation in a January 2011 report. "Businesses with large rooftops or parking lots can become small power companies that feed electricity into the grid. Community cooperatives can pool the rooftop area of their neighborhoods to form, for example, an East Oakland Power Company." The revenue could be rolled into job creation and more green-energy development.


True that ‘large scale solar is attracting billions in investment’. But only because the government has promised these profits through massive ARRA grants (free money), and risk-free (read low cost) loans guaranteed by the government. The companies investing are motivated by profit and profit alone, and they would not otherwise be interested.
Then, as you point out, roof-top solar essentially competes with utility companies for generation and distribution of electricity. Knowing this you can understand why the utility companies don’t like roof-top solar.
Several entrepreneurial companies here in California have found a solution for homeowners who can’t provide the up-front investment to put solar on the roof. These companies pay for the installation, lease the equipment to the homeowner who then pays a monthly fee to the solar company. The net is a lower total bill.
The net of all this is that the government has picked a technical solution -- big solar in the desert. Being fundamentally political, governments are not good at engineering. A government’s job is to create an economic environment that will let entrepreneurs figure the best way to do something.
Meantime, we are grievously wounding our western open space heritage, like a spendthrift heir running through an inherited fortune. We will all be poorer for this, economically and socially.
And by the way, it is looking more and more like photovoltaic is becoming the dominant big-solar technology, mainly for cost reasons. This will leave Ivanpah, committed to steam and turbines, a dinosaur in the desert.

Posted by Budlong on Jul. 14, 2011 @ 10:44 am

Bill Gates may have an expertise in computer operating systems and building a mega-corporation, but he has no expertise in alternative energy or in problem solving outside of his field, and without his big money his opinion would not get any attention. Two cents is a fair estimate of its worth.

Second, government officials always support big projects. Big projects mean they accomplish big things (whether good or bad). More importantly, it involves big money (taxpayer money). A politician who steers money to a corporation will get a percentage of the money back either in campaign contributions from the corporation, or by becoming a highly paid lobbyist or member of the board of directors of the corp. after leaving elected office. It is important to understand this.

Readers who want and unbiased and well documented discussion of alternative energy can go to: or read Community Power at

Posted by justfacts on Jul. 15, 2011 @ 2:10 pm

The Obama Administration has turned out to be one of the historically worst administrations for protecting the environment. They are making precedent setting policy that is rolling back 40 years of environmental protection. They have fast tracked big solar developments taking up to 5 to 6 square miles of desert at a time, much of it in critical wildlife habitat. They are turning out to be very good republicans.

If you examine the current situation regarding solar applications on public lands, you will notice that all of the big solar applications on desert land that are I under review now are for large 6 to 7 square mile photovoltaic (solar panels) facilities. The concentrated thermal plants (big mirrors) are white elephants and the federal money they need is gone. Photovoltaic plants are cheaper to build, but are still much more expensive than conventional power sources.

If you are using solar energy to be "green", it is utterly stupid to put these panels out there on tortoise habitat when all of the rooftops in Las Vegas have nothing on them! They could have just as easily pumped stimulus money into a feed in tarrif. Solar panels don't care if they are on you roof or in wildlife habitat.

What is very sad is that most of the environmental organizations have sold out the southwest desert habitats. A whole coalition of them are promoting a bunch of Solar Energy Study Zones being reviewed by the Feds. The end result will end up being about half a million acres of public lands that will end up having a one step approval for big developers to clear land and build millions of photovoltaic panels in pace of tortoise habitat. (they will just dig up the tortoises and move them). Why wouldn't environmental groups want these developments in disturbed areas first?

Posted by BighornNV on Jul. 16, 2011 @ 8:20 am

@BighornNV: how do you know that or in other words, are there any public site with these informations? would be great to provide the source, thanks!

Posted by Matt Reeves on Feb. 22, 2012 @ 12:58 am