Thursday, March 31, 2011

100% of world's energy from renewable sources by 2030

I think I found my utopia!
In light of the recent tragic events in Japan and the still unresolved nuclear crisis, there has been a lot of talk about the safety of and the need for nuclear energy. Intuitively I have negative feelings about nuclear power - there is something about radioactivity that is terrifying, and while plants appear to be safe and useful, when things go wrong, they go really really wrong. Lunch with my two coworkers, one Japanese, the other British (and a nuclear power proponent) has been very interesting and informative over the past few weeks. The consensus seems to be that we NEED nuclear energy and that it's the cleanest, most sustainable option out there right now.
So when I heard on the radio that a study determined that 100% of the world's energy can come from renewable sources by year 2030, I didn't really believe it. But having read the study, I now feel like I have a vision of what I would like the world to look like in the future, and a hope that is attainable after all.

The article, "A Plan to Power 100 Percent of the Planet with Renewables: Wind, water and solar technologies can provide 100 percent of the world's energy, eliminating all fossil fuels. Here's how" was published in October 2009 in the Scientific American. The authors are Mark Z. Jacobson, a professor of civil and environmental engineering at Stanford University and director of the Atmosphere/Energy Program, and Mark A. Delucchi, a research scientist at the Institute of Transportation Studies at the University of California, Davis. The plan uses only WWS energy (wind, water or solar) and would be divided thus:

Wind supplies 51 percent of the demand, provided by 3.8 million large wind turbines (each rated at five megawatts) worldwide. Although that quantity may sound enormous, it is interesting to note that the world manufactures 73 million cars and light trucks every year. Another 40 percent of the power comes from photovoltaics and concentrated solar plants, with about 30 percent of the photovoltaic output from rooftop panels on homes and commercial buildings. About 89,000 photovoltaic and concentrated solar power plants, averaging 300 megawatts apiece, would be needed. Our mix also includes 900 hydroelectric stations worldwide, 70 percent of which are already in place.

How much energy would we need and how much will be provided by WWS?

Today the maximum power consumed worldwide at any given moment is about 12.5 trillion watts (terawatts, or TW), according to the U.S. Energy Information Administration. The agency projects that in 2030 the world will require 16.9 TW of power as global population and living standards rise, with about 2.8 TW in the U.S. The mix of sources is similar to today’s, heavily dependent on fossil fuels. If, however, the planet were powered entirely by WWS, with no fossil-fuel or biomass combustion, an intriguing savings would occur. Global power demand would be only 11.5 TW, and U.S. demand would be 1.8 TW. That decline occurs because, in most cases, electrification is a more efficient way to use energy. For example, only 17 to 20 percent of the energy in gasoline is used to move a vehicle (the rest is wasted as heat), whereas 75 to 86 percent of the electricity delivered to an electric vehicle goes into motion.

What about cars, planes, appliances?

In our plan, WWS will supply electric power for heating and transportation—industries that will have to revamp if the world has any hope of slowing climate change. We have assumed that most fossil-fuel heating (as well as ovens and stoves) can be replaced by electric systems and that most fossil-fuel transportation can be replaced by battery and fuel-cell vehicles. Hydrogen, produced by using WWS electricity to split water (electrolysis), would power fuel cells and be burned in airplanes and by industry.

Among the hurdles to overcome are: financial, material and political. Financially, this will cost about $100 trillion, world wide, not including transmission. The authors feel that this money will be recovered by the energy companies through the sale of the energy. As far as materials are concerned, there are some minerals involved in the current wind and solar technology that will need to be mined and efficiently recycled (such as neodymium for wind turbine gears, lithium for batteries and tellurium and indium for solar cells). One hope is that new designs and innovations will make these materials less necessary - neodymium free wind turbines are already being designed. Politically, there are many more factors at play. Oil companies will not sit quietly by as their empire is dismantled. A great amount of collaboration is needed between countries in transmission of the energy - Luxembourg, for example, will need to get it's hydroelectric power from Germany and what about poor countries, and those who do not get along with their neighbors (Middle East? Africa?) Also, I wonder, what will happen to the Middle East when no one cares about their oil anymore?

As far as I'm concerned, none of this will happen till we run out of oil (which may be as soon as 2035), but then I see no reason why at least the developed nations can't switch to 100% renewable energy. It would of course be best if we started the transition now, spread out the infrastructure costs over 40 or 50 years for example, but I don't think the oil companies will let our politicians do anything progressive.

A large-scale wind, water and solar energy system can reliably supply the world’s needs, significantly benefiting climate, air quality, water quality, ecology and energy security. As we have shown, the obstacles are primarily political, not technical. A combination of feed-in tariffs plus incentives for providers to reduce costs, elimination of fossil subsidies and an intelligently expanded grid could be enough to ensure rapid deployment. Of course, changes in the real-world power and transportation industries will have to overcome sunk investments in existing infrastructure. But with sensible policies, nations could set a goal of generating 25 percent of their new energy supply with WWS sources in 10 to 15 years and almost 100 percent of new supply in 20 to 30 years. With extremely aggressive policies, all existing fossil-fuel capacity could theoretically be retired and replaced in the same period, but with more modest and likely policies full replacement may take 40 to 50 years. Either way, clear leadership is needed, or else nations will keep trying technologies promoted by industries rather than vetted by scientists.

Somehow knowing that it's possible, makes me feel better about the world my daughter will be born into. So some happy news at last!

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