My friend Lauren Feeney has a fascinating interview with Ray Kurzweil, the noted inventor and AI enthusiast best known for his predictions regarding the coming technological Singularity, at PBS.org. Drawing on his “law of accelerating returns,” Kurzweil predicts that revolutionary advances in solar energy, e.g., the doubling of productivity every two years, will allow us to painlessly transition from fossil fuels in twenty years:

Today, solar is still more expensive than fossil fuels, and in most situations it still needs subsidies or special circumstances, but the costs are coming down rapidly — we are only a few years away from parity. And then it’s going to keep coming down, and people will be gravitating towards solar, even if they don’t care at all about the environment, because of the economics.

So right now it’s at half a percent of the world’s energy. People tend to dismiss technologies when they are half a percent of the solution. But doubling every two years means it’s only eight more doublings before it meets a hundred percent of the world’s energy needs. So that’s 16 years. We will increase our use of electricity during that period, so add another couple of doublings: In 20 years we’ll be meeting all of our energy needs with solar, based on this trend which has already been under way for 20 years.

People say we’re running out of energy. That’s only true if we stick with these old 19th century technologies. We are awash in energy from the sunlight.

Lauren pushes back against Kurzweil’s optimism:

Feeney: You talk about what will happen instead of what might happen. But there are so many obstacles to dealing with climate change — political gridlock, consumer apathy. Are you concerned that these things might not happen because of obstacles like these?

Kurzweil: My main thesis, which I call the law of accelerating returns, is not affected by the kind of things you are referring to. The exponential growth of computation is measured in many different ways continued through the entire 20th century, completely unaffected by the little things like World War I and II or the Great Depression. It was not affected at all by the recent economic downturn. This exponential growth of solar energy has continued through thick and thin.

As the cost per watt of solar falls significantly below coal and oil, people are going to go to that for economic reasons. It won’t be a political issue.

My view is that the only way renewables will succeed is if the price really does go below that of coal and oil, as Kurzweil predicts. [I see that I've been unclear here. Allow me to elaborate: there are two ways for renewables for the price of renewable energy to become lower than that of coal and oil. The first is for technological advancement of the kind Kurzweil describes to drive down the underlying cost of renewables. The other less sustainable way is to employ subsidies. The rest of my paragraph intended to cast doubt on the viability of the subsidy strategy. I had assumed that this was clear, but it evidently was not.] Subsidizing renewables on a grand scale might make a dent in the affluent countries, but (a) demographic change will put considerable pressure on the public sector and (b) energy use will increase most rapidly in non-affluent countries that are even less likely to subsidize clean energy sources. One could argue that we need large-scale public investment to accelerate the development of breakthrough energy technologies of the kind Kurzweil anticipates, but it does seem as though the kind of technologies Kurzweil has in mind have significant commercial potential, thus suggesting that investors and entrepreneurs have a fairly strong incentives to pursue them even in the absence of large-scale public investment.

It should go without saying that Kurzweil’s predictions could prove wildly overoptimistic, as Lauren suggests. But I’m not so sure about Annalee Newitz’s gloss on the same interview:

There’s something deeply weird about comparing iPhone improvements to solar adoption, which isn’t just facing technical barriers but corporate and governmental ones.

Is the government actively working against the adoption of solar energy? As for corporate barriers, I’m not clear on what Newitz is referring to — I assume that many firms would embrace cheaper-than-coal solar energy. She might mean that oil and gas interests are working against large-scale public investments in this field, but that presumably wouldn’t prevent solar-centric start-ups from continuing to make bets on cheaper-than-coal technologies.  

I hope that Kurzweil is right. I had the great pleasure of meeting Saul Griffith, the environmentalist and inventor who has pioneered, among other things, high-altitude wind power, and my sense is that he would scoff at Kurzweil’s predictions, seeing them as complete puffery. Many of my green friends are convinced that existing political systems will break under the pressure of the kind of environmental dislocation that is already “baked in the cake,” even in the absence of an increase in emissions. When I broached the subject of air capture technology and its potential uses, one friend laughed, noting the extraordinary energy expenditure required. Joanna Borns wrote the following in Popular Mechanics in 2009:

Skeptics of the technology point to carbon emissions coming from ACCESS and similar devices themselves. Because it uses electricity from the grid to separate gas from the solution, the prototype barely breaks even in CO2savings. Global Research hopes to run future models on solar power, which would take fossil fuels out of the equation. The price of capturing the CO2 is also high, predicted to cost several hundred dollars per ton once commercially developed. “In the long term, the price will come down to $30 per ton,” Lackner says, “but this will not happen overnight.” 

Ultracheap solar energy would, of course, solve this problem.