Global Warming, Prop 87 and Investments in Silicon Valley
A few weeks ago, Stanford held their Global Climate and Energy Project workshop - three days of presentations on how we can innovate on global energy technologies to significantly reduce greenhouse gas emissions. The talks ranged from solar energy technologies to bioenergy storage to carbon mitigation / capture / separation / storage, plus a plethera of poster presentations. The key issue is a simple one - we've got to replace our energy needs - particularly coal - with carbon-free technologies to keep atmospheric CO2 under 550ppm. And that means changing our way of doing business and our way of selling lifestyles.
The solar question is simple - can we economically create a solar cell that is efficient enough (e.g. 15-20%) and dense enough to capture solar radiation? Professor Alan Heeger of UC Santa Barbara recently did a talk at PARC on the use of simple printing technologies to produce "plastic" electronics like sheets of solar cells through the use of "insulator-to-metal transition in conjugated polymers including the emergence of gate-induced metallic state in field effect transistors" ("Plastic Electronics and Optoelectronics, PARC, 9/1/06). Martin Green and Gavin Conibeer of the University of New South Wales (Australia) proposed using polycrystalline silicon thin films using silicon quantum dots to "stack" the cells, increasing efficiency up to 50%+, which is pretty amazing given most of the expensive solar cell processes produce cells that have about 20%+ overall efficiency at best (and yes, I know you can claim higher efficiencies for single wavelength conversion but let's be pragmatic). There are lots of solar advocates, and we really should be using our daylight hours to feed into the grid instead of taking from the grid. However, the solar guys are intensely disliked by the petroleum, coal, and other traditional energy supplies - after all, the solar guys want to displace their market with solar power and not make the fossil fuels market more efficient. It's a wonder I didn't see fistfights ensue.
The physics of radiative energy capture is pretty simple, but the practice given weather, sun angle, season and so forth tends to bring down the numbers. But if everyone could charge up their hybrid or electric car from solar power captured every day with a specialized device instead of add to their electric bill, I think we'd see a lot of consumer sales. I think solar is beginning to close the gap, and the market will be on reducing our dependence at the gas station and not necessarily "getting off the grid". Think what a difference in CO2 emissions that single shift would make.
There's a current big push towards biomass and ethanol conversion - Tom Friedman made a case for us sending our petrodollars to small third world countries to create ethanol out of their waste sugar cane instead of paying OPEC. He thinks we might as well use our dollars to alleviate real poverty in the world to maintain our love for SUVs instead of arming terrorist dedicated to our destruction, and cites Brazil's use of ethanol as an example we should emulate (40% of all fuel used by cars in Brazil use ethanol - for an interesting analysis of how Brazil is successful and the USA has a ways to go to meet this number due to our incredibly consumptive lifestyle, see Milton Maciel's article Ethanol from Brazil and the USA).
Right now, ethanol from corn (which would benefit the conservative lightly populated mid-American states at the expense of liberal heavily populated coast states) is the happy pill sold to alleviate all our fuel ills, thus keeping the petro companies, refiners, and distributors of fuel all in the loop (God forbid people start making their own energy - it will be the end of the oil companies). They don't want alternatives - they want to control your addiction. Friedman doesn't seem to think this is bad if we buy our ethanol from cheap third world sources and consider that money global poverty alleviation grants, but most politicians want us to buy very expensive ethanol from their backers and controlled through their distribution - which means it's too expensive even for SUV lovers.
Ethanol is what we call a migration strategy - we all know the old fossil fuels gambit we've used for a century will peeter out within the next 50 years (Dubai runs out of oil in 2012, and is hoping to become an entertainment and business mecca, which given the turbulence of that neck of the desert means they are very optimistic). Vinod Khosla sees it as a necessary migration strategy for a population that won't take responsibility for its own energy needs (go solar, get a hybrid) and will just have to have their fuel fix. Like the earlier stem cell research proposition, his Prop 87 initative wants Californians to take the lead in this area (without the feds) and pump $4B into alternative energy technologies (his investments are in alternative energy startups, so he isn't an unbiased observer or do-gooder). Richard Newton, Dean of Engineering at UC Berkeley, recently invited Vinod and Professor Ted Padzek, Civil Engineering, to a debate over the merits of ethanol, and according to Matt Marshall of VentureBeat "he came down in favor of Khosla". Why? Well, because Vinod invests in innovation - not the status quo - and he believes that ethanol is just the first step in getting ourselves out of petroaddiction. "While ethanol is critically important for the first step of the process of displacing oil, even Khosla doesn’t believe that ethanol is the final answer. Ethanol will, though, help break the back of the traditional distribution model of petro-chemicals. And then, if you can produce a higher order hydrocarbon, like butanol, you can solve the rest of the problems".
Unfortunately, Stanford didn't have much on this very topical issue, although there were a few interesting discussions of biological catalysts (yeasts, cyanobacteria). I would have liked to see more, simply because we've got a huge $4B bet on the ballot that will influence California's and the US direction for the next 20 years.
But when all is said and done, ethanol and solar probably wouldn't be enough - the third world is heavily dependent on coal (China is covered in coal dust, with major health problems growing daily) to power their economies. They don't want to invest in new technologies (neither do first world countries BTW - we have to make them do it with regulatory demands which are currently out of vogue among the "get rich at any cost" set). So we also have to create CO2 mitigation and storage strategies for coal production that are economic and feasible and we have to do them soon.
One of the most fascinating talks of the workshop was from Dan Shrag of Harvard University on "Carbon Sequestration in Deep Sea Sediments". He observes that ocean uptake is the earth's slow (limited by the mixing rate based on the earth's rotation, tides, winds, and so forth - it is the earth after all) but predictable mechanism for absorption of CO2 (80-90%). We can't increase the rate, but can we store it safely in the meantime? Many other proposals suggest we store in aquifers and mines, but cannot ensure it will not leak (monitoring is expensive as well, as anyone in IT knows). Geochemical processes are expensive, require lots of water, and produce waste products for disposal. Direct injection in the ocean is precluded by the slow rate of ocean absorption (more than 50% comes right back out, and local acid pockets are created dangerous to marine life). Finally, compensating with biological uptake mechanisms like forests (trees like CO2, remember) is just too small to handle all the stuff we're dumping into the atmosphere.
Dr. Schrag proposes a different approach - store CO2 in deep sea sediments. At high pressure and low temperature, CO2 is denser than sea water - optimally around 3000 ft (lower and you get geothermal heating effects). At around 4000 ft, CO2 hydrates impede permeability. So if we inject it into the ocean sediment below this limit, CO2 will float upwards, combine with hydrates, then condense for dissolution (it can't rise any higher). Of course, this means we place it along the coast (and not near active faults please).
The remarkable thing about Silicon Valley is how various disciplines combine together to create new and innovative solutions to our growing problems. For too long these groups have contended among themselves as the "best" solution to our theoretical energy deficit and global warming. But it is clear that, as we face actual temperature increases, changing (and damaging) weather patterns, political and cultural turmoil and war over diminishing fossil fuel resources, and a growing population demanding ever more energy, these groups need to band together. We need all of these solutions, and we need them now.