Green Tech

Solar power, it turns out, can mean more than just clean electrons and home hot water systems.

Chevron on Friday disclosed plans to use solar thermal technology from BrightSource Energy to enhance oil recovery from an aging well in central California.

BrightSource Energy's demonstration facility in Israel's Negev Desert, where an array of heliostats, or moving mirrors, concentrate light onto a tower to make steam.

(Credit: BrightSource Energy)

The system will use 7,000 mirrors on Chevron-owned land to reflect light onto a tower to make steam. The steam will be pumped underground to heat up heavy oils and make them easier to extract, according to a Reuters report. Right now, Chevron uses natural gas to make steam.

Concentrating solar power has emerged as one of the most cost-effective solar technologies for utility-scale solar projects. Using mirrors or reflective troughs, sunlight from desert areas is concentrated onto a liquid that makes steam. In a power plant, that steam turns a turbine to make electricity.

Production on the plant in Coalinga, Calif., is slated to begin by the end of 2010, Chevron executives told Reuters. Chevron Technology Ventures, the company's venture arm, is an investor in BrightSource Energy.

BrightSource Energy's main business continues to be utility-scale solar. But another young solar company, Ausra, shifted its focus from building solar power plants to using its solar thermal technology to make a system for different industrial processes.

eSolar's demonstration plant in Lancaster, Calif.

(Credit: eSolar)

eSolar is doing what so many other solar start-ups wish they were already doing: feeding electricity into the grid.

The 2-year-old concentrating solar company on Wednesday will host an event in Lancaster, Calif., to celebrate the opening of a demonstration facility that's converting the sun's desert heat into electricity.

At five megawatts--enough to supply about 1,500 homes or up to 4,000 during peak hours--it's making a modest contribution to overall electricity generation. But the Lancaster plant has been crucial to proving that eSolar's technology produces cost-effective electricity and can be replicated, said company CEO Bill Gross.

Concentrating solar power systems concentrate sunlight to make steam, which is converted into electricity through a turbine. eSolar's plant is the first to use a single tower to make steam, which is slightly more efficient than traditional reflective trough technology, according to Gross. It uses thousands of computer-controlled mirrors to reflect the light onto the tower.

He said the plant produces power at less than the retail rate for electricity in California, which is 13 cents per kilowatt-hour.

The company has signed deals to supply its technology and projects to energy project developer NRG Energy for plants in the southwest U.S. and ACME in India. Gross said those projects are expected to break ground later this year.

For a full interview with Bill Gross, see this Q&A.

While the Obama administration has expressed increasing hopes that wind power will play a key role in America's future energy system, one of the world's leading scientists is ruling out the technology.

Jack Steinberger, the 1968 Nobel Prize winner in physics and director of CERN's particle-physics laboratory, spoke at a conference of Nobel laureates at the 350-year-old Royal Society in London last week.

His conclusion: "Wind is not the future," according to the London Times.

Jack Steinberger

(Credit: Nobelprize.org)

Steinberger says Europe should cancel its big wind plans and that solar energy is the future.

Historical resources in the energy-hungry world are being depleted, he said, predicting that fossil fuels, coal, and oil will be gone in 60 years. But the solution, he asserted, is not wind power.

The reason? Wind power still requires backup power when the wind isn't blowing, and that decreases its contribution to emissions reductions.

On the other hand, solar thermal power--where collectors concentrate sunlight using mirrors and lenses to produce electric power and heat--is already economical and can handle the storage problem, he said. The heat produced can be stored, enabling solar thermal plants to produce electricity during hours without sunlight.

Steinberger now wants funding for a big pilot project.

The idea is to link solar thermal power from Northern Africa to Europe via high-voltage undersea cables. The proposed 3- to 3.5-gigawatt power plant would cost an estimated $32 billion to build. Steinberger believes that 80 percent of Europe's energy needs could be met by solar thermal power plants in the Sahara by 2050.

In the U.S., which has the world's largest installed base of wind power, the Obama administration has pinned high hopes on wind, with Secretary of the Interior Ken Salazar recently expressing hope that wind power could replace coal.

Meanwhile, the 1976 Nobel Prize winner in physics, professor Burton Richter of Stanford University, agreed that solar energy is a promising new technology, but speaking at the Royal society conference, did not want to rule out wind as a future energy source.

At Abengoa Solar's facility in Spain, mirrors heat a liquid in a tower, on right, that produces steam to make up to 20 megawatts of electricity.

(Credit: Abengoa)

Abengoa Solar of Spain on Monday reported successful tests of its second solar tower in operation, in which the sun's heat is used to make electricity.

The 531-foot solar tower, located near Seville, Spain, features a number of improvements on the first design and has exceeded the anticipated output. Called PS20, the installation is the largest in the world with a capacity of 20 megawatts, enough electricity to supply 10,000 homes, according to the company.

A solar tower configuration uses a field of heliostats, or mirrors, to concentrate sunlight onto a receiver held in the tower. The heat creates steam which turns a turbine to make electricity. The PS20 project has 1,255 of these heliostats, with each heliostat having a surface area of 1,291 square feet.

Concentrating solar thermal technology has been used in desert areas in Spain and the southwest U.S. for decades and is seeing a resurgence as utilities seek out cost-effective solar power.

The traditional solar concentrating power uses rows of mirrored troughs that follow the sun over the course of the day.

Solar tower technology is considered the successor technology to mirrored troughs and is being pursued by a number of solar companies, including renewable energy powerhouse Abengoa and California start-ups BrightSource Energy and eSolar.

Abengoa Solar said that this installation improved on the first solar tower in Spain with better control systems and solar thermal energy storage system.

Utility Southern California Edison on Wednesday announced a giant solar energy contract with BrightSource Energy, which could eventually result in powering 845,000 homes with the sun's energy.

Through a series of seven projects, SCE intends to purchase up to 1,300 megawatts of electricity from BrightSource Energy's solar towers that use heat to produce electricity.

Although the companies didn't provide a price tag for the deal, it's one of the biggest solar energy contracts to date in the U.S. and a validation of solar tower technology. The project still needs to be approved by regulators and financed.

BrightSource Energy's demonstration facility in Israel's Negev Desert where an array of heliostats, or moving mirrors, concentrate light onto a tower to make steam.

(Credit: BrightSource Energy)

The first project from the deal is scheduled to be a 100-megawatt installation in Ivanpah, Calif. which could be operating in early 2013, supplying 286,000 megawatt-hours of electricity per year, or enough for 65,000 homes.

Concentrating solar technology uses reflective troughs or mirrors to concentrate light onto a liquid to make steam. The steam then runs a traditional electricity turbine.

The technology, best suited for desert climates, is being revived in places like California which have a mandate to produce 33 percent of their electricity from renewable sources by 2020.

BrightSource Energy uses mirrors to reflect sunlight onto a tower to heat water which makes steam. The Google.org-backed company, which has roots with developers who did solar thermal projects in the 1980s, says that its air-cooling process preserves water, an important consideration for desert projects.

Several concentrating solar companies were founded in the past five years, but the credit crisis and economic downturn has made it very difficult to finance these expensive projects. One BrightSource Energy competitor, Ausra, has shifted its business strategy away from giant solar power plants.

California utility Pacific Gas & Electric is expected to announce a large solar deal, which will involve solar photovoltaic panels, some time this quarter.

New Jersey utility Public Service Electric and Gas Company on Tuesday announced that it has applied for a $773 Million Solar Energy program to make 120 megawatts of electricity.

Updated at 10:00 a.m. PT with comments from Ausra providing more detail on its strategy.

Because of a lack of financing, solar-technology company Ausra has dropped plans to make massive solar-thermal power plants in favor of smaller, cheaper units.

Ausra President and CEO Bob Fishman told different news outlets this week that the company has been forced to change its business strategy in response to the credit crisis. The company is also laying off staff as part of the reorganization, according to reports.

Ausra's pilot solar-thermal power plant in Australia.

(Credit: Ausra)

The change is a clear sign of how the credit crisis and the current structure of government incentives are hurting the business for large-scale renewable-energy projects.

Backed by top-flight Silicon Valley venture capital firms, Ausra has designed equipment for concentrating solar-power plants. Specially shaped glass plates reflect light to create heat. The heat makes steam, which then drives a turbine to make electricity.

Several new companies have formed with different designs for concentrating solar power, or solar-thermal energy, with an eye toward building power plants in the southwest. California utility Pacific Gas & Electric has contracted with Ausra and others to buy electricity from these planned projects through a contract called a power purchase agreement (PPA).

But Fishman said the financing simply isn't there for solar-power plants that rival the size of coal or natural-gas plants.

"What a lot of people thought when they went out and signed 500- or 900-megawatt power purchase agreements was that it was easy to go from a 1-megawatt demo plant to a 900-megawatt project,'' Fishman told the San Jose Mercury News. "That's simply not reality. The finance market will not support it."

Instead, the company intends to make and run small to midsize power-generating facilities--on the order of 50 megawatts, he said. The company will also emphasize its business of licensing its technology to other project developers and utilities.

Ausra vice president of communications Katherine Potter said that the company still thinks that the business for large-scale solar power is viable. But the company is adjusting to the market conditions by focusing on equipment sales.

The company could, for example, sell a solar field as part of an existing coal or natural gas power generation facility. The solar power delivers electricity at peak times during the day, offsetting a utility's carbon emissions.

Financially, it's easier to do because utilities can deploy Ausra's equipment in six to 18 months, Potter said. By contrast, Ausra's deal to provide 177 megawatts worth of solar power to PG&E will take a few years just to get through the permitting process, she said.

Investors and solar executives say that, even with strong demand, a lack of money to finance projects means that other solar start-ups will either shift strategies, scale back plans, or go out of business.

Renewable-energy investments get a 30 percent federal tax credit. The recession means that fewer corporations expect to have a tax bill to offset, which means that there's a dearth of "tax equity" available to invest, according to financiers.

Last week, PG&E CEO Peter Darbee said the California utility will invest in solar-power generation directly because of the tax equity problem. By building and operating its own solar-power generation facilities, rather than working with a project developer, PG&E can benefit from the tax credit.

Solar power is one of the most heavily invested areas within clean tech, making it a crowded field. Because financiers are being particularly conservative, new technologies will likely have trouble being deployed at a large scale this year.

"I think it's going to be a brutal, brutal year for solar, and a lot of companies will go out of business," said Andrew Beebe, the CEO of Suntech Energy Solutions, which develops solar-power facilities for corporations and utilities. "A lot of mistakes were made. Now is the time of reckoning, and it's going to be ugly."

Update on October 13, 2008 6:30 a.m. PT: Corrections to the SkyFuel's relationship to NREL and it's projected cost of delivered electricity.

Even with the teetering economy, solar companies are bullish that tapping free energy from the sun is a solid financial move.

SkyFue on Friday is hosting an event to unveil its solar power plant system: a parabolic trough made from reflective plastic. Colorado Gov. Bill Rittner will speak at the event, held at SkyFuel's research center in Arvada, Colo.

SkyFuel's parabolic trough, made with reflective plastic rather than mirrored glass, a design which it says lowers the overall cost.

(Credit: SkyFuel)

Parabolic troughs have been around for decades and are considered the incumbent technology in concentrating solar thermal power plants, which are suited for hot desert climates like in Spain and the U.S. southwest.

Reflective troughs concentrate sunlight onto a liquid which is converted to steam, which turns a power generator.

SkyFuel's enhancement on the basic shape is a trough that uses silver encased in plastic, rather than mirrored glass. Although silver is certainly an expensive material, using plastic cuts down on the overall cost, according to Chris Huntington, vice president of business development at SkyFuel. The company's founder tested the designs extensively with the National Renewable Energy Lab in Colorado.

He said that the cost of an installed solar power plant using its equipment is about 25 percent less than existing parabolic troughs.

The company estimates that it can profitably deliver electricity below the concentrating solar power benchmark of 15 cents per kilowatt-hour. That's the price of other solar thermal technologies, but still more than a natural gas or coal power plant.

Using a solar trough installation at an existing power plant, where there would not be the need to purchase a steam turbine would lower the cost significantly, Huntington said.

Several solar thermal companies have sprouted up in the past five years, with different designs such as Ausra's Fresnel lens glass reflectors or eSolar solar power tower.

Demand is driven by state-level renewable portfolio standards. Utilities in California, for example, need to purchase 20 percent of their electricity from renewable sources by 2010.

Huntington said the company expects to have a small installation of its SkyFuel system--on the order of 2 to 10 megawatts in size--in the next year and then larger installations after those pilots.

Having a less cutting-edge design than other firms is an advantage in a tight funding market, Huntington said.

Click on the image to see a photo gallery of different concentrating solar technologies.

(Credit: Ausra)

"The cost of borrowing is going up everywhere and there will be a tighter credit market. But if any money is going to be spent on CSP (concentrating solar power) plants in the near future, I think it's going to be on tried-and-true systems like the parabolic trough," he said.

The company is already working on the second generation product that will include storage through a Department of Energy grant. It probably won't be commercially available for at least three years, Huntington said.

Rather than heat up oil or hot water, the parabolic troughs will heat up tubes of molten salt. That salt can be stored to make electricity even after the sun goes down.

BrightSource Energy has raised $115 million, a hefty vote of confidence for its solar power tower technology that converts heat to electricity.

Investors included Google.org, the philanthropic arm of Google, as well as VantagePoint Venture Partners, BP Alternative Energy, Statoil Hydro Venture, and Cargill subsidiary Black River. Existing investors DBL Investors, Draper Fisher Jurvetson, and Chevron Technology Ventures also participated in the Series C round.

A drawing of a power tower where a field of heliostats concentrate light on a tower that houses a steam turbine.

(Credit: BrightSource Energy)

BrightSource designs and operates solar power plants aimed at utilities that need to invest in renewable energy. Pacific Gas & Electric said in March it will purchase up to 900 megawatts from BrightSource solar power plants. It plans to start construction in 2009.

Solar thermal systems are considered cost-competitive with natural gas power plants, particularly for "peak" power which typically happens in the afternoon. They work best in desert environments; existing plants are in the Southwest U.S.

Using mirrors or lenses, sunlight is concentrated onto a liquid which makes steam that turns an electricity turbine.

The most traditional solar thermal technology is a power plant designed around a series of mirrored troughs. BrightSource, by contrast, uses a field of heliostats, or mirrors, to reflect light onto the top of a tower where a steam turbine is.

BrightSource senior vice president for marketing and business development Charles Ricker, who spoke on a panel at a clean technology investor conference in New York on Tuesday, argued that troughs will be phased out in the coming years in favor of other systems.

Power towers are more efficient and require less capital to make than trough solar thermal systems, he said.

The primary driver behind solar thermal technology, which works best in desert areas, is California where some utilities need to make renewable energy part of their power generation mix.

The state's renewable portfolio standard is set at 20 percent by 2010 and 33 percent by 2012, Ricker explained.

To date, BrightSource has raised $160 million.

That ancient, inefficient heating/air conditioning system in your building might be worth something someday.

Pacific Gas & Electric CEO Pete Darbee said in a briefing with reporters Tuesday that the utility is working with government officials to see if there is a way to create a fund that gives building owners financial incentives to replace old compressors, pumps, and other building equipment with new, energy-efficient versions.

Building owners want to get rid of this old equipment, he explained, but the capital requirements are a big hurdle. The program could be structured in a way so that it could be funded partly through the utility bills paid by the customer.

The program would, in some sense, be similar to the residential energy rebate programs PG&E has run for years. Under those, PG&E gives cash rebates to homeowners who replace old washers and dryers with new ones. The utility has also underwritten programs to get consumers to replace incandescent bulbs with energy-efficient compact fluorescent bulbs.

Energy efficiency is the top priority in PG&E's effort to reduce greenhouse gas emissions. For one thing, energy conservation is less taxing on the environment than even getting more power from renewable sources of energy like solar panels.

Energy efficiency is also far cheaper. Technology for energy efficiency costs about 3 to 4 cents per kilowatt-hour, Darbee said. Harvesting energy from a renewable resource might cost 10 to 15 cents a kilowatt-hour or more. Rooftop solar panels have historically hovered around 40 cents a kilowatt-hour, he said. Energy efficiency standards implemented in California in the '70s also show that the programs work--energy consumption per capita has stayed relatively stable in the state since then but have risen substantially in other parts of the nation. Efficiency allowed California not to build 24 power plants in the last 35 years, he argued.

"The fact that you don't use power is the best strategy," he said.

Darbee, who has helped put PG&E at the forefront of greening utilities, spoke at length on a number of topics. Here are some of the highlights.

--PG&E is examining ways it can own its own solar thermal plants. Solar thermal plants--large, sprawling complexes that generate megawatts' worth of electricity from heat from the sun--are far more cost-effective than solar rooftop panels. "With solar farms, you can get down to 10 cents a kilowatt-hour," he said.

Technically, PG&E can build a solar thermal plant now, but it wouldn't qualify for the investment or production credits. That would put PG&E at a 30 percent cost disadvantage. Thus, if it can get that law changed, PG&E might build its own plant. Right now, the utility signs contracts to buy solar thermal-generated power from third-party companies like BrightSource Energy.

Why would it want to build and own solar plants? Solar thermal plants cost millions of dollars, and the start-ups trying to build them don't have the same capital as a major utility. A hiccup in the regulations or electricity demand could become a terminal setback for a start-up. PG&E could ride out such storms.

--He's not wild about a California ballot initiative to get 50 percent of the state's power from renewable sources. "There may be a time when 50 percent seems reasonable, but right now it seems too far out of reach," he said. Nonetheless, it could be possible to raise it from the current 20 percent level to 33 percent in the future. It depends on the state of renewables and the transmission grid.

--Nuclear power will likely make a comeback in the U.S., but the resurgence mostly might occur in the Southeast and other regions where renewables don't work as well. Besides, resistance among segments of California's population could make it difficult to build more nuclear plants there.

"Demand for power is so great in the U.S. that nuclear should play a role," he said.

--Plug-in hybrids could help promote wind power. A lot of wind power gets generated at night, but since few are awake to use it, it goes to waste. With plug-ins, that power could be used to recharge batteries. The utility is also working with Google and others on technology that would identify cars on the grid. With this, drivers could plug in their cars at work, and then sell power stored on their batteries back to the utility for peak prices. You'd buy at night when power is cheap and sell it in the day when it's expensive.

--He likes the idea of wave power, but building something that can survive the ocean won't be easy, "How do these technologies hold up in the Pacific when things get really nasty?" he posed. "What is clear is that you have constant motion in the ocean."

Correction: This story was corrected to reflect the day the briefing was held. It was Tuesday, April 30.