A High-Tech Entrepreneur On the Front Lines of Solar  

Todd Woody (who seems to be writing for half the green business periodicals in the US) has an interview with (solar thermal power company) eSolar CEO Bill Gross at Yale Environment 360 - A High-Tech Entrepreneur On the Front Lines of Solar. Gross talks about how techniques from the software industry are being applied to continuously improve the performance of next generation CSP plants, how the Chinese market is moving much faster than that in the US, how eSolar tries to build smaller plants on private land close to cities to avoid the transmission bottlenecks plaguing remote locations currently and what is needed to make CSP cost competitive with coal fired power.

Bill Gross is not your typical solar energy entrepreneur. In a business dominated by Silicon Valley technologists and veterans of the fossil fuel industry, Gross is a Southern Californian who made his name in software. His Idealab startup incubator led to the creation of companies such as eToys, CitySearch, and GoTo.com. The latter pioneered search advertising — think Google — and was acquired by Yahoo for $1.6 billion in 2003.

That payday has allowed Gross to pursue his green dreams. (As a teenager, he started a company to sell plans for a parabolic solar dish he had designed.) Over the past decade, Gross has launched a slew of green tech startups, including solar power plant builder eSolar, electric car company Aptera, and Energy Innovations, which is developing advanced photovoltaic technology.

But it has been eSolar, backed by Google and other investors, that has been Idealab’s brightest light. In January, the company signed one of the world’s largest green-energy deals when it agreed to provide the technology to build solar farms in China that would generate 2,000 megawatts of electricity — at peak output the equivalent of two large nuclear power plants. And last week, eSolar licensed its technology to German industrial giant Ferrostaal to build solar power plants in Europe, the Middle East, and South Africa. Those deals followed eSolar partnerships in India and the U.S.

ESolar’s power plants deploy thousands of mirrors called heliostats to focus the sun’s rays on a water-filled boiler that sits atop a slender tower. The heat creates steam that drives an electricity-generating turbine. Last year, eSolar built its first project, a five-megawatt demonstration power plant, called Sierra, in the desert near Los Angeles.

This “power tower” technology is not new, but what sets the company apart is Gross’ use of sophisticated software and imaging technology to control the 176,000 mirrors that form a standard, 46-megawatt eSolar power plant. That computing firepower precisely positions the mirrors to create a virtual parabola that focuses the sun on the tower. That allows the company to place small, inexpensive mirrors close together, which dramatically reduces the land needed for the power plant and cuts manufacturing and installation costs. ...

e360: Were there any particular lessons you were able bring from the Internet industry to the solar industry?

Gross: The biggest lesson that we brought was — I don’t know if it was a lesson, but it was a philosophy — which is Internet-enable everything and put monitoring into everything.

So we have a microprocessor in every mirror and we have statistics second-by-second on the status, position, reliability, pointing accuracy — everything — of every single mirror. We structured ourselves almost like an Internet company from the beginning to have logs of everything — every revolution of the turbine, every control from the control room, every Web cam image captured — so we could do data mining and data analysis on everything.

We want the ability to make software upgrades and impact every power plant around the world. That’s probably one of the biggest differences between our technology and all other solar technology. If you [have] a big field of [photovoltaic] panels, those PV panels are there for 25 years. They’ll have that same performance, and there’s nothing you can do to change that.

We can make a software upgrade and every power plant in the world can suddenly put out 3 percent more power potentially. And we found already a number of software improvements that we can make even over the past six months, which significantly boosts performance of an already-constructed power plant. There’s new improvements we can make to the actual hardware, too, but even without changing the hardware there are software changes that can make more power, so we’re really excited about that. ...

e360: At a time when some big solar power plant projects are bogged down in disputes over their environmental impact on desert ecosystems and their water consumption, eSolar so far has avoided such controversies.

Gross: We have a strategy at eSolar to never impact pristine land. And the way we address that is several-fold. First, we have a higher output per acre, so we take a smaller footprint. Second, we’re economical at a smaller size. We can be fully economical at our 46-megawatt size. Those two things combined let us use a small enough footprint that we can locate on private land closer to population centers.

So rather than needing 2,000 acres contiguous to make the economics work — which you almost only can find far away on pristine land or [federal] land — we can locate on only 200 acres very close to a city and we can buy previously disturbed farmland or other properties that’s already been developed so we’re not causing any disturbance to natural habitat. And that’s an important part of our philosophy. It gives us an economic advantage because we’re locating closer to transmission. That’s probably even a bigger factor.

It takes years and years to build the transmission out to the pristine lands. [But] the power plant, for example, in Lancaster [California], is across the street from a transmission line. We didn’t have to build miles and miles of transmission, which takes years and years to get people to approve. ...

e360: Where do you see the next big innovations in solar thermal technology coming from?

Gross: I feel we still need to get almost another factor of two in the reduction of energy costs to potentially compete with coal. We’re already close to competing with natural gas. It depends on the sunshine and the region. Another factor of two is going to require two things to make that happen: Approximately 25 percent of that can be gotten by adding [energy] storage, and 25 percent can be gotten by increasing efficiency and lowering costs by volume production.

We produced 500 mirrors two years ago, 24,000 last year, and this year we’ll produce a million. So we’re going to get a quantity break just by going to a million mirrors from 24,000.

And everything gets more efficient in the supply chains as you get up to those volumes. Anything that we buy in our lives that has dramatic cost reduction has seen a million — a million cars, or a million iPhones, or a million laptops. So far there’s only been thousands of heliostats. So finally this year we’ll cross the million number and that’s when we can get the price reduction to really be competitive with fossil fuels.