ROBERT SIEGEL, HOST:
From NPR News, this is ALL THINGS CONSIDERED. I'm Robert Siegel.
Tomorrow, the National Academy of Sciences will release a report on the need to anticipate and cope with abrupt changes in the world's climate. Risks of a nasty surprise are growing as carbon dioxide builds up in the atmosphere. Most of it comes from fossil fuels, and dealing with those emissions is no easy task. The world would have to reduce carbon emissions from coal, oil and natural gas 80 percent by mid-century to sharply reduce the risks of climate change. And nations are far from that ambitious path. But technologists do see a way, at least for the United States to achieve that goal. NPR's Richard Harris takes a look at what it would involve.
RICHARD HARRIS, BYLINE: The National Renewable Energy Laboratory sits on a hill overlooking Golden, Colorado and the suburbs that sprawl all the way to downtown Denver. The researchers here at this government-funded lab are in the business of dreaming about a clean energy future.
KEITH WIPKE: Oh, there it is. So when I start this up...
HARRIS: Keith Wipke, for example, drives an experimental car fueled by hydrogen.
WIPKE: So that's water dripping out of the tailpipe, and that's all that comes out of these vehicles. True zero emission vehicle from the tailpipe.
HARRIS: The lab makes its own hydrogen using solar panels and wind turbines. No fossil fuels are involved in powering this car. Inside one of the lab's efficient, solar-powered buildings, Dave Bobela and Kevin O'Neill are part of an army of researchers trying to develop new solar technologies. The cost of solar cells has plummeted in the past few years, and they're working on next-generation technologies to keep that momentum going.
KEVIN O'NEILL: And then what about sliding your substrates in and out? Are you doing long glass rods?
DAVE BOBELA: The push-pull rod, yeah.
HARRIS: People have been hoping for clean energy for decades. And for decades, the world has relied overwhelmingly on the much cheaper fossil fuels. Coal and oil and natural gas made up 82 percent of total energy 25 years ago, and they still make up 82 percent of world energy today. To find out what it would take to budge from that mark, I sat down with Douglas Arent. Our eyes adjusted easily to the low light in a meeting room which was illuminated only by reflected sunlight.
DOUGLAS ARENT: You've experienced some of the building, huh? Some of the cultural changes.
HARRIS: Arent co-authored a major study to look at a piece of this challenge. It asked whether the United States could rely on wind and solar and other renewable energy supplies for at least 80 percent of our electricity by the middle of this century.
ARENT: You know, our results from a technical nature show that you could meet demand every hour of the year with up to 80 percent of it coming from renewable resources.
HARRIS: Not to say it would be easy.
ARENT: There's lots of challenges of getting there. The grid would have to be much more flexible. I think the utility model of the future would have to look different. And, of course, in the ideal case, our economically ideal case, we would build much more transmission.
HARRIS: That vastly expanded transmission grid would help pull wind and solar energy from thousands of miles away. So a windy day in Wyoming can make up for a calm day in California. Those new transmission towers could prove too expensive or they could generate local opposition. If that happens, Arent says we'd need to find a way to store a huge amount of renewable power so it can be used when it's needed.
ARENT: What we found was that there were many different pathways and that there wasn't a red flag that said it was impossible, at least at the level that we looked at it.
HARRIS: This renewables-only report makes one huge assumption. It says we would need to meet all our future demand for more and more electricity by tightening our belts and using electricity more and more efficiently in our homes and gadgets and machines. So no additional power would be generated for our growing nation. That's a tough goal. Interestingly, the price of generating power from wind or solar turns out to be a comparatively small concern in Arent's analysis.
ARENT: In many instances and in many markets, renewables are in fact competitive today.
HARRIS: There are about a dozen optimistic reports that suggest our energy future can be built exclusively with renewable sources like wind and solar. But many other reports say not so. Renewables alone can't go the distance.
At Stanford University, Sally Benson heads the Global Climate and Energy Project. She challenges her students to think of reducing emissions from all energy sources, not just electricity but transportation fuels, gas furnaces and industrial processes.
SALLY BENSON: And the big class project is to - basically to design a transition scheme that allows us to get from where we are today to an 80 percent reduction in emissions. But I also say, well, you know, you have to think about the industry, you know, you can't lose jobs, and we have to have enough energy so that, you know, people aren't freezing and, you know, going without lights and so forth. So it has to be sort of a reasonable scenario.
HARRIS: Remarkably, she says, the classes eventually reach a conclusion that mirrors what a lot of expert panels have found when they look at this problem. You can do it, but it takes a lot more than using less energy and relying on renewable sources.
The solution the students inevitably arrive at requires steady, reliable and large-scale sources of clean energy. That means capturing carbon dioxide from fossil-fuel plants and burying it underground and also producing a substantial amount of nuclear power.
BENSON: So it's definitely an all-of-the-above strategy. You have to do all of them at a really significant pace, and you need to be reducing the carbon emissions every year at a pace of about 2 percent per year. And you need to be reducing your energy use by an equivalent amount.
HARRIS: And the cost? Well, we would eventually double the investment we're making on energy infrastructure today.
BENSON: It's big but - I mean, obviously, we spend a lot of money on other things today, and some of that would need to be diverted towards, you know, a cleaner energy infrastructure.
HARRIS: Clearly, the prospect of higher energy prices is a challenge for an economy that craves cheap energy. But Benson says those higher prices would still be a small fraction of the total economy.
So are you feeling optimistic about a transition to a clean energy economy?
BENSON: I think there's lots of good news on the technology side, and I think all the smartest engineers and scientists at universities around the world are - not all - many are focused on this challenge. And the students love this. This is what they want to devote their life to. So from that perspective, I am quite optimistic.
HARRIS: Benson's amazed that more than 10 percent of her colleagues on the Stanford faculty are doing at least some work trying to resolve the clean energy problem. And surrounding Silicon Valley is also full of entrepreneurs looking for ways to cash in.
BENSON: What I'm not optimistic about is what seems to be our total inability to make any decisions, or the society to work together, to some of these long-range, challenging problems.
HARRIS: And, she says, the longer we wait on this one, the harder it gets. Richard Harris, NPR News.
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