The power world is dominated by coal, gas and nuclear, with some large hydropower in selected spots. Most people believe that it is likely to stay that way for some time. But there are more and more stirrings of a science-driven revolution, a transformation in how we generate our power. There is something deeply unpopular about each of our current big sources of electricity, nothing that has in any way upset society's love of electricity, but just the way we get it.
OK, I accept that for most people the way we get our electricity is by flipping a switch, and it is very much an 'out of sight, out of mind' provision. Still, if you are living in a big Chinese city, (and there are a lot of them), even if you can't see the power plant you can certainly see the air, and that ain't good. And even if you are pretty oblivious to concerns about climate change, you might at least have heard about Russia cutting off winter supplies of gas to some of its neighbors in disputes over prices. Or heard a lot of confusing and contradictory rhetoric around the desirability of new nuclear power plants. More about the science behind that another time.
Now in this world of claim and counterclaim, it is interesting to see just how change has occurred in some places. In 2008 wind power (onshore) in Spain generated more electricity than coal for the first time, though still behind gas and nuclear. In 2009, there were many days when wind was the leading generator of power in Spain. And given a reasonable regulatory regime, the levelized cost of onshore wind power is as low as that for gas, and cheaper than everything else. So I think we have arrived at a point, at least for onshore wind, where a second form of renewable energy has taken its place among the big generators. Moreover, it is less geographically specific than large hydro.
I make this point in part to split apart the mass of technologies that are called 'renewables', because they are very different. Some are commercial on utility scale and able to compete reasonably well at wholesale prices, others are very far from that. Some are amenable to use at small scale (for example rooftop solar PV or solar hot water) and others are only sensible at megawatts and above. Some of these technologies need scientific breakthroughs (which will almost certainly happen) to get to commercial competitiveness, while others can only drive down costs based on better engineering and manufacturing.
I want to pick this apart with some examples. The cost of the active module of solar photovoltaics has been falling rapidly. This is a combination of exploitation of research in materials science over the past 30 years, and application of manufacturing techniques, much of them learned from the semiconductor industry. And this is not incremental improvement. Rather costs have fallen by as much as 75% in just a few years. Of course the active PV material is just a part of the finished generating kit, so the levelized cost of power from solar PV has not fallen as quickly. Nonetheless, when your most costly component drops in this way, it gives impetus, motivation, for getting the costs of everything else down. And this will happen, and I believe happen quickly, over the coming three-five years. So solar PV is science driven, and manufacturing enabled. We are not finished with the scientific progress either. There are results just coming out of the leading nanotechnology laboratories, outcomes of research over the past decade, that promise another step change of lower cost and higher efficiency for PV.
These nanotechnology developments are also important for lighting. Solar power is light in and electricity out. LED lighting is electricity in and light out. The same devices, or very nearly, can do both. It seems clear to me that in a decade or less all of our lighting will come from LEDs, and most of these will be the products of our basic materials science investment in nanotechnology and nanofabrication.
Another area where science promises to play a leading role is next generation biofuels, biochemicals, and biomaterials. This is the third wave of biotech, following from pharmaceuticals and agriculture. It promises to take us way beyond ethanol derived from corn or sugar cane. And in so doing has the ultimate promise of addressing our energy challenges and the problem of accumulation of waste from urban societies. We must reduce the volume of waste, but to the extent that the waste we do generate can be feedstock for our energy needs, that is a good outcome. Bioscience holds the promise of making that outcome a reality.
Biofuels are not a risk free area. When energy crops are involved, we of course have to price in the risks of disease, weather, and the fickleness of nature in to our energy costs. And the science here is still developing -- yes there are commercial products making their way to market, but we still have a decade of development ahead of us. I know many people think of any kind of biofuels as competing with food for scarce land resources. But in the last year I have been listening to a lot of scientists who work on agricultural productivity, and they all have the same message: We can develop plants that double the production from the same land area, with little or no increase in fertilizer demand. If so why haven't you done this already? Because there just has not been the demand for it.
But why concentrate just on fuels? Chemicals and materials require volumes with higher values, and there is a big effort to make more of these from biological feedstocks rather than petrochemical ones. A good mantra here is to use biology to make things that are hard to make by chemistry.
So if solar PV and biofuels/biomaterials are science driven renewables, what are the engineering/manufacturing driven ones? Wind, wave, tidal (tidal stream and tidal range), 'utility scale' solar thermal. This is rotating machinery, deployed in sometimes difficult conditions, but it is all about engineering rather than science. And that means cost reductions will be eked out over years of experience, rather than step changes resulting from new science.
Some doubt the value of encouraging this sort of revolution to occur, and worry about increasing the cost of electricity. I don't. We have the opportunity to accomplish several desirable goals -- reduce greenhouse gas emissions, eliminate fuel price volatility, increase the diversity of our energy supply and improve energy security, and create new manufacturing jobs -- while we create the energy infrastructure for the 21st century. Push the science, refine the manufacturing, deploy at scale that which is ready, and set high standards for the next generation of technologies. It's as simple and as difficult as that.