The Rice Solar Energy Project will produce enough electricity to meet the demand of 60,000 households—about 150 megawatts—beginning in 2013. Click here for a full-size version of the diagram. Courtesy of SolarReserve.

In a world energy landscape dominated by coal, gas, oil, and nuclear, renewable energy sources such as wind and solar don’t stand a chance if we can’t find a way to store energy when the sun doesn’t shine and the wind doesn’t blow. In my last blog entry, I wrote about storing electric energy in a battery made of paper and nanotech ink (see The Paper Battery Chase). But it isn’t necessary to store electric energy. We can create hydrogen, using electricity generated from photovoltaic panels, and then use the hydrogen to fuel a fuel cell, which recreates the electricity. The Leaf Community in Italy is experimenting with this process. And energy changes forms in other ways. We can store heat from the sun and use it to create electricity in the dark. As in any energy storage and conversion process, if we can do it without losing too much energy in the process, we can add another tool to our renewable energy toolbox.

I add a little salt to the water when cooking spaghetti—it raises the boiling point so that you can cook the pasta more quickly, although I’m not sure it makes a big difference. Mostly I add salt to make the spaghetti taste better. The properties of a liquid salt—a mixture of sodium nitrate and potassium nitrate—are a little different. This liquid salt will store heat up to a temperature of 1,000⁰F, which is much higher than the boiling point of water, 212⁰F at sea level. The Pacific Gas and Electric Company, (PG&E) has contracted with SolarReserve LLC to store energy using liquid salt. The Rice Solar Energy Project will produce enough electricity to meet the demand of 60,000 households—about 150 megawatts—beginning in 2013.

The Rice Project uses a large circular field of mirrors to reflect light onto a central tower. Liquid salt is circulated through the tower and, once heated, it is stored in an insulated tank. When the sun goes down the liquid salt will still be able to heat water well past the boiling point to create steam, which can be fed into a conventional steam turbine to produce—Walla—electricity. The liquid salt, now cooled, is stored in another tank and is ready to begin the process all over again.

Take that coal, gas, oil, and nuclear!

This 1928 home in Albemarle County, Virginia recently
underwent a renovation through the EarthCraft Virginia
existing homes renovation program. After the renovation,
electricity use dropped by 24% and energy costs dropped
by 42%.

Home Energy Magazine is celebrating its 25th anniversary with a special May/June issue. We're taking the opportunity to look back at the past several decades of energy policy in America, and look ahead to what may come. Here's a sneak preview of some of what we're thinking.

Alan Meier, Senior Executive Editor, and Steve Greenberg, Technical Editor, among others, lived through the first energy crisis precipitated by the Arab oil embargo in 1973 and its aftermath. They remember the sudden interest in energy efficiency and renewable energy; the proliferation of solar water heaters on the roofs of homes that broke down quickly, had no one trained to fix them, and have become rusted monuments to the best of intentions gone wrong; the sudden and short lived gain in the average car’s fuel efficiency. They also recall some major successes: the huge and lasting increase in appliance efficiency, especially refrigerators; the success of the Energy Star program; and California’s progressive Title 24 building standards.

Alan, in a yet-to-be-published editorial, has been musing on what will happen after the billions of dollars from the American Recovery and Reinvestment Act (ARRA) have been spent on building and retrofitting more efficient and sustainable buildings. Will it be the same three steps forward, two steps back pattern that we’ve seen before? Not so, according to Alan, if we:

Steve came up with some powerful images to stimulate our thinking about the future of energy efficiency:

We've been on a ramp with a rather gradual (and usually upward, with notable exceptions) slope. Suddenly the ramp gets so steep it looks like a wall. If we make it to the new, much higher level, what does the terrain look like? Do we go off a cliff, completing a boom and bust cycle the likes of which we've never seen? Or is there a reasonable ramp down to a sustainable level?

I lived through the lines for gasoline, though I couldn’t yet drive. I've observed the resulting interest in miles per gallon instead of horsepower; the return to a horsepower-mentality; and the recent switch back to a concern about miles per gallon. My family had a great experience with our new-fangled heat pump in the early 70s. My Dad, an engineer and all-around handy man, first got me interested in how houses and cars work during that time. I guess I vote for a steep, but not impossible ramp up in efficiency, followed by a less intense, slow and gradual climb that continues for a long time, with sudden jumps due to new, undreamed of (or only just dreamed of) technology. The pressure will come from high energy prices and people starting to feel the real effects of global warming and unhealthy air. I don't think these things will change anytime soon.

Areas where the oil spread after the spill. See this map and others.

And November's the month last year when the Cosco Busan crashed, leaking 53,000 gallons of black goo into San Francisco Bay.

So biologists will be particularly attentive this November, one year after the oil spill, to see if there's a noticeable dip in the numbers of herring in the Bay, or the number of migratory birds that alight here.

The number of birds harmed by the oil spill is not really known. More than 2,000 birds were killed – but those are simply the birds that were identified, not the total number. Since many dead birds in remote areas were never found, and since predators took away many of the hurt birds, the estimate for the total number of birds harmed by the spill is many times higher than that. So researchers are conducting experiments to determine a provable, scientific estimate of the number of birds killed or harmed by the oil spill.

According to California Fish and Game scientist Julie Yamomoto, it only takes a spot of oil the size of a nickel to harm a bird. It's not just uncomfortable, she says, it's actually lethal – because the oil is like a hole in a wetsuit, and birds that have been oiled become hypothermic. And they also lose buoyancy, so birds can actually sink and drown in the ocean.

All the experiments and data on habitats, fish, birds and other wildlife will be compiled into something called the Natural Resource Damage Assessment.

It's nicknamed NRDA (pronounced "nerd-a") and that's pretty apt. It's a little wonky, to say the least. The data is supposed to be completed by the end of next year, and then the NRDA report is expected to be compiled and submitted sometime in 2010.

Listen to the Oil Spill Anniversary radio report online.

You may listen to the "Chevron's Plans" Radio report online, as well as find additional links and resources.

Amy Standen is a Reporter for QUEST and Radio News at KQED-FM.