Imagine that every car in America was an Electric Vehicle (EV) powered by a electric battery like the Tesla’s (Nasdaq: TSLA) Roadster. Imagine also that each and every car was powered with solar energy. Here’s a question: what amount of land would you need to generate the solar energy to power every electric vehicle in America? And how would that solar acreage compare with the land surface that the oil industry uses to drill today?

I did the numbers and the answer will surprise you.

Part of the angst with the recent BP (NYSE: BP) oil spill in the Gulf is that many think we are addicted to oil and therefore can’t stop drilling. U.S. Presidents since Nixon have proclaimed our addiction to oil and after announcing their plans for energy independence oil demand has gone up. I have a different view.

We’re not addicted to oil. We are addicted to driving.

It is highly unlikely that as a society we’ll stop driving anytime soon. The good news is that we can drive as we have been while not polluting the Gulf, import oil or use oil at all. The way to do it is to shift the way we power our cars – from gasoline to electricity – and power those cars with the sun. I have previously predicted that the last commercial Internal Combustion Engine Vehicle (gasoline car) will be built around 2030.

So assuming all cars in America are battery electric vehicles and we drove exactly the same number of miles we do today, let’s calculate how much electricity we would need to power all of them.

Electric Vehicle Battery Power

Americans drive around 3 trillion miles (4.8 trillion Km) per year, according to the U.S. Department of Transportation (1). How much electricity would be consumed driving all those miles?

I assume that Lithium-Ion battery can power an electric vehicle for about 4 miles (6.4 Km) per kilowatt-hour (kWh). This is slightly lower that the advertised mileage of three battery electric cars as shown on the following table.

So 3 trillion miles divided by a mileage of 4 miles per kWh means that Americans will need 750 billion kWh annually for driving.

Now let’s calculate the total land needed by solar power plants to generate this much electricity in a year.

Solar Land Needs

The total power generated for a given land area will be given by the following formula
Power Generation = Land Area * DNI * Sunlight-to-power efficiency
(see the definitions and my assumptions below):

I’m using 15% efficiency and a DNI of 2,000 kWh/ m2/yr (see notes below for more).

Resolving for Land Area we get:
Land Area = Power Generation / (DNI * Sunlight-to-power efficiency)
= 750 billion kWh/year / (2,000 kWh * 0.15)
= 2,500,000,000 m2
= 2,500 Km2
= 965 square miles

So here’s the number: 965 square miles (2,500 Km2). That’s less than 1,000 square miles!

What this means is that a solar square with 31.1-mile sides (50 Km) could generate all the energy that would power every single car in America (assuming they were all electric vehicles.)

Ted Turner’s ranch in New Mexico is about 244 square miles – so he alone could generate enough electricity to power 25% of all cars in America. A solar plant the size of King Ranch in Texas with its 1,289 square miles could generate all of America’s electric vehicle power with 30% extra electricity to spare – maybe export it to Mexico?

The solar number is 1,000 square miles. Let’s compare this number with what the oil and gas industry uses today to power our gasoline cars.

Oil & gas land use

According to the U.S. House of Representatives, oil and gas companies lease 74,219 square miles (47.5 million acres) of land in the United States to drill oil. They also lease a further 44 million acres (68,750 mi2) for offshore drilling (1). Adding these two numbers we get that the oil and gas industries lease 143,000 square miles from the U.S. government—to meet just about a third of America’s transportation needs.

So to power just about a third of our cars, oil companies need 143 times the land that solar would need to power every single car in America (assuming they were all electric vehicles.)

Needless to say, oil drilling leaks and spills damage more land and water than the above numbers reveal. The BP (NYSE: BP) Gulf Oil disaster has damaged tens of thousands of square miles beyond its drilling permits. As of June 2010 the U.S. National Oceanic and Atmospheric Administration (NOAA) Fisheries Services had closed an area around 80,000 square miles of water from commercial fishing.

The BP Oil Spill alone is eighty (80) times larger than the desert land that solar CSP plants would need to power every car in the United States (assuming they were all electric). And no one has ever heard of a solar spill.

The conclusion is simple: oil is not just dirty – oil is a land and water hog. Solar is more than 100 times more land efficient than oil – without the pollution.

What does this mean to entrepreneurs?

When the most abundant source of energy on earth (solar) is also is 100 times more resource efficient than the competitor (oil) the message is clear: the transition from oil to solar to is going to happen. It’s just a matter of when not if. As the car industry also transitions to electric vehicles keep in mind this solar number: just 1,000 square miles of solar plants in the desert can power all the (3 trillion) vehicle-miles driven every year in America. That’s what I call “Solar Trillions”!

Definitions, Notes and Sources

Battery Electric Vehicle range and mileage like gasoline car mileage will depend on many factors, including the car itself (weight, quality), driving conditions (city, highway, traffic, weather), driver, and so on. Furthermore, not all Lithium-Ion batteries are made equal. The number I came up with was based on a decidedly unscientific sample of three battery electric vehicles (Tesla Roadster, BYD E6, and Nissan Leaf) from three different countries (US, China, and Japan). I used 4 miles per kWh of battery.

DNI = Direct Normal Incidence radiation. DNI depends on the location. I’m assuming the solar plants are built in desert land in the U.S. Southwest, which generally have high DNI. A solar plant in Barstow, CA, may receive more than 2,700 kWh/m2/yr while Las Vegas, NV, or Tucson, AZ, receive about 2,560 kWh/m2/yr. I used 2,000 kWh/m2/yr.

Sunlight-to-power efficiency = What percent of the solar radiation (DNI) is converted to power. This number also depends on the technology used. Thin film photovoltaic might convert less than 10% while Dish Sterling CSP efficiency may be closer to 30%. Solar CSP with Combined Heat and Power (CHP) can have an efficiency of 75%-80%.

However, you need extra land for things like roads, power block, offices, and so on. I used 15% efficiency. Expect this number to go up over the next few years as new innovations, learning curve, and scale advantages kick in.

Sources:

(1) “The Truth About America’s Energy: Big Oil Stockpiles Supplies and Pockets Profits,” A Special Report by the Committee on Natural Resources Majority Staff,” U.S. House of Representatives, Committee on Natural Resources, Rep Nick J. Hall – Chairman, June 2008

I was interviewed by Robert Linton on the Green Numbers Radio Show. Here are some excerpts and links to the interview.

Radio interview, Part 2

Robert Linton –There’s a worldwide water crisis right now. Tony, could you tell us the real relationship between solar and water?

Tony Seba – Sure. Water, as you may know, is very tightly linked to energy. You need energy to produce, transport, and clean water and you need water to produce energy. For instance, in California 19% of our electricity is used to transport water from one place to another.

Desalination, meaning production of clean water from seawater, has gone up 10,000 percent over the last forty years. In part, this is because there’s been growth in areas which already have a water crisis. Desalinating, cleaning water, is very energy intensive.

Saudia Arabia and other Gulf countries, for instance, burn about 1.5 million barrels of oil per day to desalinate water. This is about $120 million dollars per day to desalinate water.

Clearly, burning fossil fuels to power these desalination plants is not financially or environmentally viable. And so solar desalination is the only way to desalinate and clean water for the future.

RL: Wow, that’s amazing. You’ve spoken about the clean energy economy and it will transform other industries. Specifically, say, for example a data center, with their service, and trying to keep them cool, or maybe with a company with a sun chip as a food manufacturer. How can clean energy help transform those industries?

Tony Seba: One of the interesting opportunities that I explored and I found was that of solar air conditioning, solar chilling, which, when you think about it, people do a double take…“What do you mean solar, which is heat and chilling which is cold?” But in fact, to run a chiller, you need hot water, not just electricity but also hot water, and most of the energy that’s used in data centers… two thirds of it… two thirds of a data center’s budget goes into air conditioning, into chilling. So if you put these two things together, you use solar energy to heat the water, and then you use a chiller with that solar hot water to chill data centers. And that is one way in which solar energy will transform not just electricity generation but also will transform data centers and so on.

You mentioned food production. Frito Lay has a plant right here in California that produces SunChips and SunChips used to be made with gas and of course saying “Gas Chips” would not sell a lot of chips, but now they’re being heated with solar power. There’s this technology called parabolic troughs which concentrates the sunshine and it generates steam, which heats the oil, which fries the chips, and that technology is in use today.

RL: You know with solar energy, I know there’s going to be a huge impact as far as how it will affect life in the developing world. Say for example in the Marshall Islands in July of 2008, they had a blackout. How would solar help prevent that from happening in the future, could you talk about this incident?

Tony Seba: Yes, one of the big opportunities that I found, I call “island-scale solar” and the example of the Marshall Islands is one of them. The Marshall Islands went bankrupt in July of 2007 because the whole island is powered by diesel fuel which comes from oil. And in July 2008, oil hit a peak of $147 per gallon. These islands could not afford to buy the oil, so they went dark. And that’s not the saddest thing. The saddest thing is that these are sunny, perfectly sunny islands in the South Pacific and they were paying for diesel power two to three times what they could be paying for solar energy. And there are thousands of islands around the world that are in the same predicament… sunny islands that are paying two to three times for dirty power, what they could be paying for solar power.

And not only that, I can tell you there are millions of villages around the world that are pretty much like islands in the sense that they’re not grid-connected. Just to talk about India, there’s half a billion people who live in half a million villages that are not grid connected. And this is a problem, but solar power does not need a grid, so you can power all these half a million villages in India for less than what they are paying today for diesel or kerosene.

RL: You know, Tony, a lot of my listeners are investors… could you tell us about the one or the two trillion dollar opportunities that our listeners may not have heard of, or maybe some market opportunity that you see that really scaled to market?

Tony Seba: Absolutely. The book has many, but let me give you two, and we started the conversation about two multi-trillion dollar opportunities. One of them is solar air conditioning. The peak rates that we pay for electricity in the United States are when the sun is heating the most. So we’re paying for air conditioning, for instance, 40 cents, 50 cents, and the new rate in California is $1 per kilowatt hour, when you could perfectly have a solar air conditioner which is basically solar receivers on top of your house with a chiller that can generate pretty much electricity for free. And this is a multitrillion dollar opportunity. You can use solar chillers, like I said, for data centers, for houses, for buildings, for warehouses… There’s going to be a massive transformation that’s going to generate solar chilling.

Another one is what I mentioned, village-scale solar which involves villages around the world that are not grid-connected which can generate their own power with solar. Just to give you an example, just to tell you how exciting this is for me, I taught this course, the “Clean energy Market and Investment opportunities” course last Fall at Stanford and at least (to my knowledge) half a dozen folks who took that course went on, basically left their jobs, to start solar-related clean-energy companies, and one at least, has got offers from investors to invest in them. This is only after a few months. It’s so exciting that it’s already happening so quickly.

RL.: How do you compare this emergence with Silicon Valley in the past, and also, Tony, is America leading the way for the clean energy revolution?

Tony Seba: That is a good question. We are building great technologies, we in Silicon valley we are used to building technologies and putting them in the market, in companies and so on. In the past, we really did not need anyone else to do this, so we built Cisco, Apple and Intel, Google and so on. But clean energy, energy itself, is very different, because in energy, the biggest driver, the main driver, is government policy. Energy companies have been subsidized and are being subsidized by one account, 200 billion dollars go into subsidies for fossil fuel energy, coal, oil, and nukes every single year…

RL: It doesn’t make sense anymore.

Tony Seba: It doesn’t. But not only that, the laws and the rules, the land use regulation are stacked in favor of incumbents of fossil fuel energies. So we need the right policies from Washington, from Sacramento, from the government, to make clean energy happen. And I’m not talking about subsidies to solar, I’m talking about the need to stop subsidizing the fossil fuel industry, which, by the way, is the largest industry and the most profitable industry in the world. In that sense, Silicon Valley is not really leading the clean energy economy. Countries like Germany that have had the right policies over the last 10 to 15 years have created a couple hundred thousand clean energy jobs, and they lead, for instance, in solar photovoltaics.

RL: Tony, I’d like to thank you for coming on my show today. I would like to welcome you back when you come back, I know you have a trip overseas to look at some prospects for investments. When you get back I’d like to have you come back on the air. I really appreciate you coming on today, and all my listeners, definitely pick up his book, Solar trillions, you can go to tonyseba.com to look at his website. Tony, thank you very much.

I was interviewed by Robert Linton on the Green Numbers Radio Show. Here are some excerpts and links to the interview.

Radio interview, Part 1

Excerpts:
Robert Linton – This is Robert Linton, your host for Green Numbers Radio Ask the Experts Show. Tony, for you new book Solar Trillions, what is the premise?

Tony Seba: Well, Robert, thanks for having me on the show today. The premise is simple: the clean energy economy will provide the largest wealth-building opportunities in history. The world will spend $382 trillions in energy over the next 40 years and every aspect of this industry is up for grabs: from generation to transportation to energy storage to use. And Solar Trillions shows seven of those business opportunities that are worth trillions as the title says.

RL: Outstanding. I know you spent a lot of time researching for this book. Could you highlight some of the major findings in this book as far as solar?

Tony Seba: Sure. In researching the book I looked at energy starting from the year 2050, so forty years from now and then I backtracked.

RL: How did you pick the year 2050?

Tony Seba: 2050 because a power plant is a forty year investment, so every investment that we make today is going to last forty years. I looked at the science of energy (where do sources come from?), I looked at the technology aspects of energy (How are we going to store it, generate it and use it?). And the findings are fascinating, actually:

1) No other primary source of energy can scale like solar can. Nothing comes even close. Just to give you an indication, just one hour of sunshine can power the whole planet for a whole year. Therefore the 21st century will be powered mainly by solar.
2) The architecture of energy will change radically. By this we mean the way we transform, generate, transmit, and use energy in 30 years will be totally different from the way we do it today. This is what some call “Electricity 2.0”.

Then, when I put together these two findings, I realized how gigantic these opportunities are going to be and it’s going to be mostly solar.

RL: Wow, that’s amazing. You know there are a lot of myths right now regarding solar power. Could you dispel some of those myths based on what you found in your research and actual facts?

Tony Seba: Certainly. The first big myth is that solar power is too expensive. The truth is that for more than two, maybe three billion people around the world, solar is already cheap. They mostly get their energy from kerosene or diesel and pay up to $2 per kWh. By comparison, in America pay about 10 cents. There are a couple billion people paying $2, so by comparison, solar is about 20 cents today. So it turns out that solar is already cheaper by 50 to 90% for a couple of billion people.

RL: Especially if you take away the incentives that they give to the fossil fuel industry.

Tony Seba: Exactly, that doesn’t take into account all the subsidies and so on. Another myth is that solar has an energy storage problem, meaning that it doesn’t really work when the sun goes down. And the fact is that there is a solar plant in Spain that has 7 hours of storage. This technology is called molten salts, it’s cheap and environmentally safe and it means that they general solar power for 7 hours after sundown, which is pretty cool, huh? And Spain is building a solar power plant that is going to be open 24/7 which basically demystifies all these things have been said about solar.

And another one that I want to tell you about is the myth that solar power = equal = solar panels on a rooftop, which is what we see. In fact, most of the solar power that’s ever been generated comes from a technology called Concentrating Solar Power (CSP), which uses mirrors, not PV, out in the desert. And just to give you an indication, the Economist (the magazine) recently said that this is a single solar CSP plant being built in the Mojave Desert that is going to generate more than all the solar panels that were purchased in the US last year.

RL: In your book, Tony, you compare the clean energy economy to the information economy. They sound so different, but how are they related, though, because there are some parallels between them.

Tony Seba: Yes, and the way I see it today, 2010, equals the computer industry in 1980, thirty years ago. And I’ll tell you what I mean by that. Thirty years ago, the computer model was a big mainframe out there, and users (who were “dumb”) were here. Data was scarce and was controlled and expensive. Then, the PC (personal computer), the Internet and the cell phone came around, and totally transformed the architecture of computing and created new trillion-dollar industries or many. And now pretty much anybody can use, transform and store data, which thirty years ago was unthinkable.

Similarly, in energy today the model is that you have the big mainframes, the big power plants out there, and the “dumb” users in here. So the technologies that are being built right now are similar to what the PC and the Internet and the cell phone are for information, so that in thirty years, energy will be cheap, energy will be social, pretty much anybody will be able to generate, transform, use and store energy just the way that we can with data.

RL: In your book, you wrote about the creation of a clean energy economy. What do you mean?

Tony Seba: That’s a great question since there seems to be no clear definition; it means different things to different people. In principle the clean energy economy encompasses all economic activities from sourcing energy to generation, distribution, storage, and use of energy. Since basically all aspects of our economy consume energy, you can define the clean energy economy any way you want. In the book, I focus on 7 aspects of clean energy, and that includes the whole value chain of these opportunities, including solar, large-scale solar, island scale, clean water, the smart grid, and so on.

RL: So they have to scale to the trillion dollar market before you consider them in your book, is that correct?

Tony Seba: Yes, what I did in the book is I asked myself three questions:
1) Is this source of energy clean?
2) Will it scale… scale to massive proportions, trillions of watts per year? And
3) Is it now or will it soon be financially viable?
And those were the questions that I asked myself. Wind and solar by the way get high grades. Most other sources fail at one or all three.

RL: Water is one of my pet-peeves as far as how we misuse it. And most of the time, we actually only look at water when it comes from the spigot, but given the fact that we are facing a water crisis, it’s unusual to hear about clean water, in the same conversation as energy and especially solar, can you tell us about that?

Tony Seba: Certainly, water is a huge issue. And in my opinion, while a lot of people talk about peak oil, I think that peak water will be here before peak oil, from Australia, to the Middle East to Africa, even America, water is going to hit massive crisis proportions.

RL: Hold that thought, we need to take a commercial break…..

Listen to Part 2 of this interview – Click here…

Imagine a world where you can buy electricity from your choice of vendor (not the utility) at prices that can be negotiated with the vendor. Kind of like shopping at eBay or Amazon. Want to buy a week’s worth (1,000 kWh) of power from SebaSolar at 9 ¢/kWh? Just click here. How about switching to WindyWelly for the weekend (300 kWh) at 8.5 ¢/kWh? Click! Wait, NeoGeo just announced it has a ‘fire sale’ at 7 ¢/kWh for next Tuesday through Thursday. Click!

Well, imagine no more. This electricity world exists today. To see this new architecture of energy at work I went to Wellington, New Zealand.

Powershop is a unit of Meridian Energy, the largest electricity generator and retailer in New Zealand. “The vision of Powershop is to be like eBay for electricity,” says CEO Ari Sargent. “Any electricity generator in New Zealand, including Meridian’s competitors, can offer their own brands of electricity at different prices and different times.”

I think it’s also a bit like the iTunes Store since nothing really gets shipped. Just as iTunes moves electrons Powershop moves electricity.

Many countries require their electric utilities to buy the clean power generated by residential or commercial solar or wind installations. The utilities in turn resell this power back to other consumers. That is probably Electricity 1.5. Powershop goes beyond that. In the Powershop architecture, I could build a small 1-MW solar power plant and offer the “SebaSolar” brand on the Powershop Store. I could sell this electricity directly to consumers at prices that I set—not the utility.

This means that today New Zealand consumers probably have the most choices any electricity user has anywhere in the world.

Powershop has built a plug-and-play technology architecture. While Meridian Energy is the only one currently selling power (under different brands) on this website, anyone should be able to sell power to anyone else. Just as iTunes transformed the world of music, this could be a transformational technology in the power industry.

Powershop’s revenue model is more like an internet company than the energy industry: Take a percent of each transaction. They don’t charge “connection fees” like many utilities (cable and telephone companies included) or transaction fees. Transactions are as simple as can be.

New Zealand, a country the size of California with a population smaller than that of the San Francisco Bay Area, has created a relatively open, competitive power market that offers consumers choice and some of the lowest electricity rates in the developed world.

Welcome to Electricity 2.0!

[Note: this Op-Ed was published by the San Francisco Chronicle Sunday May 23, 2010]

Most energy-industry accidents are small, so we don’t notice them. But every so often we wake up to really horrifying spectacles: the 1989 Exxon Valdez oil tanker accident, the 2008 coal ash mega-spill in Kingston, Tenn., the 1986 Chernobyl nuclear disaster – or the BP oil spill in the Gulf of Mexico.

Regulation, innovation, increased spending on safety and more care about lives and the environment all can help, and they have. Still, anyone who thinks there won’t be another hideous accident in those shiny new “clean” coal power plants or “beyond petroleum” offshore oil rigs or “clean and safe” nuclear plants is in denial.

To paraphrase former President George W. Bush, “we’re safer, but not safe” from industrial accidents. The good news is that by 2020, we can make offshore oil a thing of the past. Not by regulating or outlawing dirty energy, but by making it obsolete. Two technology trends point the way to the end of oil.

One of these trends is the downward cost curve in electricity storage – car batteries. Battery-electric vehicles are five times more energy-efficient than gasoline-powered ones. They also are five times cheaper to operate and maintain. Today you can “fill up” an electric car for about $5. Compare that with your sport utility vehicle.

The main reason electric cars are not popular is that batteries, which account for 50 percent of the cost, are expensive. Today’s lithium-ion battery costs about $1,000 per kilowatt-hour of electricity storage fully installed. The Tesla Roadster, for instance, is a $100,000 luxury car with a 53-kilowatt-hour lithium-ion battery. Tesla Motors CEO Elon Musk says batteries fall in price 8 percent per year.

But Elon’s Law looks increasingly conservative. China’s BYD Auto recently announced an electric car with a 48-kilowatt-hour battery priced at $40,000. This means the battery would cost around $500 per kilowatt-hour – which puts BYD years ahead of the curve.

Every major European and Japanese auto company has announced development of new electric cars. And just last week, Tesla Motors announced a partnership with Toyota Corp. to build electric cars in the recently closed Nummi plant in Fremont. Add all the industry and academic research and investments in electricity storage startup companies, and we can expect the cost curve to be pushed further down.

So electric cars are likely to be priced just about the same as gasoline ones by 2020 and cost five times less to maintain and operate. This is when the mass migration from gasoline cars to electric cars will start.
I expect the last commercial gasoline-powered car to be produced when batteries cost $100 per kilowatt-hour – by 2030.

But if we use electric cars while their power comes from coal or nuclear, all we have done is shift the pollution and the risk of industrial accidents onto other dirty energy sources. Coal produces worse pollution than does oil.

Luckily, the other key technology trend is the ever-faster drop in the cost of solar power. We expect solar costs to drop 80 to 90 percent over the next decade. This means that by 2020, unsubsidized solar power will be cheaper than subsidized coal, oil and nuclear.

Photovoltaic technology is improving fast – in cost, efficiency and form. Dow Chemical (NYSE: DOW) recently announced that it will launch a line of solar photovoltaic shingles. Just by replacing our old roofs with solar shingles instead of the asphalt kind, we soon could be generating solar power for less than 1 cent per kilowatt-hour. (The average American pays 10 cents per kilowatt-hour, while in California we pay up to 46 cents.) At this cost, you’d be able to “fill up” your electric car for 53 cents. Goodbye oil spills.

To move the solar-power needle faster, we need to build large-scale concentrating solar power plants. According to the Economist, a single plant being built by BrightSource Energy in California’s Mojave Desert will generate more power than all the photovoltaic panels installed across America last year. Furthermore, by going clean, America can save $1 trillion per year in fossil-fuel energy costs.

We have the technologies to make oil obsolete. But the transformation of our infrastructure will require Washington to help with proper policies. Let’s make the gulf spill our energy Sputnik moment. The choice is ours.

Solar Power Tower is one of the most important  technologies of the emerging clean energy economy.  I believe that over the next few years power towers will be one of the fastest growing and most important forms of solar energy generation.

Last year I went to sourthern Spain to visit PS10 the world’s first commercial solar power tower.

PS10 (Plataforma Solar 10) is located within Abengoa Solar’s Solúcar Solar Park, located about 16 miles (25 km) northwest of Seville.  The complex is as ambitious a solar project as exists anywhere in the world. By the time Abengoa Solar is finished building Solúcar it will have a capacity of 300 MW and generate enough electricity to power a city the size of Seville.

The PS10 tower has a height of 330 feet (110 m) PS10 tower and has a generating capacity of 11MW. Launched in the fall of 2006, it generates 24.3 GWh of electricity per year—about enough to fully power 5,500 homes.

Concentrating Solar Power

When most people think about solar power, they think of photovoltaic (PV) panels on the roof of a house or building. PV converts photons directly into electricity. PS10 and other CSP (Concentrating Solar Power) plants use the sun’s energy to generate power in a different way. It uses the sun’s heat to heat a fluid (water) to generate steam which then drives a turbine to generate electricity.

If you’ve ever used a magnifying glass or better yet a concave mirror to focus sunlight and burn a hole in a piece of paper, you get the idea. Use thousands (or millions) of square meters of mirrors (not PV panels!) to reflect that same sunlight on a single point, and you can heat a fluid flowing past it up to several hundred degrees Celsius and use that superheated fluid to drive an industrial-scale turbine.

Mirrors not PV

The mirrors are called heliostats.  Heliostats can be of any size but Abengoa engineers decided to use 120 m2 (1,292 ft2)  mirrors -  sides measure  10 m (30 ft) by 12 m (36 ft). The more mirrors the more sunshine is focuse on the tower and the more power it can generate.  PS10 has 640 heliostats for a total mirror surface of 74,800 m2 (800,000 ft2.)

Tony Seba PS10 Tower and Heliostats.

At PS10 they use water as the main transfer fluid.  Water goes up one side of the tower and gets heated to about 250 ºC (500 ºF) and pressurized to 40 bar (580 psi) as it runs through the receiver on top of the tower.  The receiver is actually composed of four large panels set in a semi-circular fashion inside a square ‘hole’ or ‘cavity’ on top of the tower.  Each one of these panels is 5.5 m (18 ft) wide and 12 m (39 ft) tall.  The cavity is 11 m (33 ft) by 11 m (33t), slightly larger than one helliostat.

Once the water is super-heated within this cavity it goes down on the other side of the tower where it generates electricity the old fashioned way: by driving a turbine.    (Large fossil fuel- and nuclear power plants use the same principle: heat water to run a turbine which generates electricity. The main difference with power towers is that they use the sun as fuel. )

Thermal Energy Storage

PS10 also has about 1 hour of energy storage.  This means that this solar plant can deliver steady power to the grid even when there are cloud covers or high winds that interrupt the steady generation of steam.  In fact, when I visited PS10 high the plant operators had to shut down the heliostats for a few minutes due to high wind conditions.

The plant kept generating power despite this drop in solar energy input.

PS20, the taller tower in the video, opened a few months after my January 2009 visit.  It is 50% taller (165 meters or 540 feet) and users 1,255 heliostats (about twice as many as PS10). PS20 has nearly twice the heliostat mirror surface and a generation capacity of 20 MW or about twice the generation capacity of PS10.

Future of Solar – Desert Power

The smaller towner between PS10 and PS20 is a research tower.   Dubbed Eureka, this tower allows Abengoa Solar to experiment with materials and technologies at ever higher temperatures – beyond 1000 ºC  (1832 º F).   The higher the receiver temperature the more power a tower can generate with the same solar input.   Compare this with surface temperature of the sun which is about 5505 °C (9941 °F) .

As we move forward to a clean energy economy, Solar Power Tower will generate a increasing part of our power around the world.  This technology works best in high solar radiation desert-type conditions. There are new solar power towers being built or planned around the globe – from the Mojave desert in California to the Sahara desert; from Spain to Israel; from Australia to South Africa .

Want to lower your utility bills or even get energy for free? Companies like Dow Chemical are developing solar shingles and other innovative technologies to turn your home into a personal power plant. Energy will be essentially free.

Three decades ago information was expensive and scarce. Data processing was autocratic, monolithic, and centralized. There were big mainframe computers ‘out there’ and ‘dumb’ users here. The personal computer, the internet, and mobile telephones changed all that.

Today information is essentially free.

San Francisco Building - Power Plant of the Future (© Tony Seba)

Scarce data turned into the Internet torrent and now data is so abundant that the first company who helped us intelligently filter this onslaught of information became the most successful company of the last decade: Google. Today information technology is distributed, grid-independent, and scaleable. Now billions of people with a mobile phone, personal computer, and internet connection can generate, store, process, and publish data. The basic architecture of information technology changed.

Energy is where data was three decades ago.

Today energy is expensive and scarce. Energy is autocratic, monolithic, and centralized. There are large power plants and refineries ‘out there’ and ‘dumb’ users here. We dig deeper into the ground, further out the oceans, or blast mountain tops altogether to get access to limited, increasingly expensive, and dirty sources of energy. But new energy generation, storage, transmission, and usage technologies are going to change this architecture of energy and turn it on its head. Energy will be abundant, clean, decentralized, and embedded.

Better yet, energy will be essentially free. Here’s an early example of a technology that will get us there.

A Personal Power Plant In Every Home

Recently the Dow Chemical Company (NYSE: DOW) announced that it was getting ready to go to market in 2011 with a new line of products: Solar Shingles . Solar shingles are basically shingles that are manufactured with embedded photovoltaic technology.

While many think of photovoltaics in terms of flat roof solar panels, there is a whole new market opportunity in a concept called “Building Integrated Photovoltaics” or BIPV. Dow Chemicals estimates this market will grow to $5 billion in just 5 years . As its name implies, solar photovoltaic technology is being designed to be part of the fabric of residential and commercial buildings. Companies like Suntech Power already have a number of BIPV products . Photovoltaic glass, for instance, replaces a conventional windowpane, or, in the form of clear glass tiles or bricks, supersedes conventional architectural glass in awnings, skylights, and clerestory panels.

Roof shingles and windows that generate electricity? It’s got to be expensive, right? Dow Chemicals estimates that roofs built with their shingles will cost twice as much as a standard asphalt roof. However, Tom Faust, CEO of Corte Madera, CA, BIPV startup Redwood Renewables may be a step ahead.

I asked Mr Faust to estimate the costs and benefits of solar tiles to a ‘typical’ Southern California home. He told me that Redwood can provide a non-subsidized fully installed 5kW system on a 2,000 square foot roof for a cost to the end user of $20,000 – $25,000. “Compared to an asphalt shingle roof without solar at around $15,000 – $20,000, Redwood¹s complete solar roofing system comes at a $6,000 premium to a non-solar roof. A homeowner using 8,000kWh annually over a 15-year span would incrementally pay under $0.09 ¢/kWh for the integrated solar system.”

This means that the effective (incremental) cost of electricity with solar shingles would be less than 1¢/kWh. Note that the “average” American pays about 10 ¢/kWh. Hawaii residents pay up to 52.17 ¢/kWh . In California the peak summer A6 rate is 46.77 ¢/kWh . Now visualize those summer power bills go down 90% from $300 to $30!

As BIPV follows the downward technology cost curve, solar tiles, solar bricks, and solar windows will approach (maybe beat) the cost of traditional tiles, bricks, and windows. BIPV homes will not just sit there: they will be personal power plants. The energy they generate will be essentially free.

Microsoft’s original mission circa 1980 aimed to “put a PC in every desk and in every home” which at the time looked naïve if not positively crazy. When IBM entered the PC market in 1981 they gave the industry credibility and helped energize the whole market. In the end it was ‘startup’ companies like Microsoft, Intel, and Apple who put a PC in everyone’s home. In doing so they helped liberate information and make it free.

Now Dow is doing an IBM in the BIPV world. Many established and startup companies are vying to build the personal power plants in everyone’s home. Eventually they will liberate energy and help set it free.

On May 14, 2009, the San Diego Regional Water Quality Control Board announced that it had approved a $320-million desalination plant with capacity to provide 50 million gallons (200 million liters) of clean water per day when completed in 2012 . In a state known for its sometimes acrimonious opposition to desalination plants (on environmental grounds) the decision to build the San Diego plant was unanimous. As of mid-2009 there were 20 more desalination plants waiting approval in California. Clean Water has clearly become a huge issue in the Golden State.

Clean Water, Dirty Power

Water desalination is energy intensive. Desalination plants follow the traditional energy pattern: most of the energy comes from burning fossil fuels and thereby emitting CO2 and dumping other forms of pollution into the environment – including water streams.


While the desalination plant press releases don’t mention the energy component,  every desalination-plant investment has to be coupled with parallel investments in power plants. According to the World Bank, “the typical ratio of power to water was 50MW: 22,500 m3/day water.”  The San Diego desal plant will produce 200,000 m3. Following that ratio, the San Diego desalination plan would need the equivalent of a brand new 444-MW power plant to provide the energy for cleaning the saltwater.

Burning coal to clean water seems dysfunctional, to put it mildly. According to the Union of Concerned Scientists, the “typical” 500-MW coal plant generates 193,000 tons of sludge, 125,000 tons of ash, and 10,500 tons of nitrous oxide (NO2)—the equivalent of half a million old cars on the road. . All of that garbage goes on or in the ground somewhere. If it is buried it may end up seeping into the groundwater, which gets polluted with toxic waste, including mercury and arsenic. That of course would decrease the supply of clean water and spur the development of more desalination plants. Dysfunctional indeed.

Clean water needs clean energy. Burning fossil fuels to clean seawater or brackish water is unsustainable and unaffordable in the long term.

Entrepreneurs who find ways to lower the energy use to desalinate water and those who find ways to clean water with clean energy have a huge opportunity ahead of them.

Sources:
“Desalination Plant is Approved,” The New York Times, May 14, 2009, http://www.nytimes.com/2009/05/14/science/earth/14aquifer.html?_r=1&scp=3&sq=desalination&st=cse

World Bank, “Seawater and Brackish Water Desalination in the Middle East North Africa and Central Asia,” Final Report, December 2004

Union of Concerned Scientists, http://www.ucsusa.org/clean_energy/coalvswind/c02d.html