Caltech Professor Nate Lewis warns that the world will need roughly twice as much carbon-free power by 2050 as all the carbon-based power we have today. In those 40 years, the human population of the planet is projected to grow from 6.6 billion to roughly 10 billion.
The bottom line, according to Lewis' calculations, is that we'll have to go from about 16 terawatts (16 trillion watts) of peak power today, to roughly 32 terawatts by 2050. Lewis makes a good case for why our energy sources going forward must be carbon-free, but even ignoring the climate change issue, we still have a stark problem: energy demands will double in 40 years.
While the 10 billion humans of 2050 can try to meet that demand by burning fossil fuels and building additional nuclear power plants, do we really want to go that route? Leaving climate change aside, is reliance on fossil and nuclear fuels in an era of skyrocketing demand a workable, long-term, energy policy for the United States and the world?
The coal, hard facts
Let's look at coal first. Currently the United States gets more than half of its electricity from coal-fired plants, while 96 percent of the sulfur dioxide pollution from U.S. electricity generation comes from coal plants - along with 93 percent of nitrogen oxide emissions, 88 percent of carbon dioxide emissions, and 99 percent of mercury emissions.
We've been able to control a lot of those sulfur emissions to reduce acid rain, but mercury is a more difficult problem. A 100-megawatt (MW) coal-fired power plant emits about 25 pounds of mercury a year, half of which can travel up to 600 miles from the plant. In 1994, the EPA estimated that U.S. coal-burning plants were emitting 51 tons of mercury a year, and it takes as little as 0.002 pounds a year to contaminate a 25-acre lake so badly that the fish are unsafe to eat.
Oil's well that ends well
We could burn oil instead - at least for now. But, according to a June 2007 edition of the UK newspaper The Independent, the end of oil will come sooner than oil companies project:
BP's Statistical Review of World Energy... appears to show that the world still has enough 'proven' reserves to provide 40 years of consumption at current rates... However, scientists led by the London-based Oil Depletion Analysis Centre, say that global production of oil is set to peak in the next four years before entering a steepening decline which will have massive consequences for the world economy and the way that we live our lives.
As discoverable petroleum reserves dwindle globally, inevitably the price of oil will rise. The trick in this situation, the policy thinkers tell us, is to avoid a scenario in which the price rises quickly, causing economic shocks.
Step on the gas
It appears that we have a plentiful supply of natural gas in North America and that there are massive reserves elsewhere in the world as well. Unfortunately, the sophisticated new extraction techniques that allow us to claim more reserves can be damaging to the landscape; some require explosions to fracture underlying bedrock. Ultimately, though, no one really knows precisely how much natural gas exists until it's extracted, which doesn't exactly sound like a solid foundation on which to build an energy future.
Nuclear meltdown
China has announced plans to build 100 nuclear plants that will produce a total of at least a gigawatt of power. But that's only one-tenth of a terawatt!
And, according to a 2008 report by Synapse Energy Economics, the total construction cost for each recently built 1,100-MW nuclear plant has been running $5,500/kW to $8,100/kW - or between $6 billion and $9 billion, bringing the total price tag for those upcoming plants to somewhere between $600 billion and $900 billion. Times 10 to get to one terawatt. And then add however many terawatts you think we'll need on top of that for a prosperous 2050.
The total cost of nuclear power is breathtaking, even if actual generating costs are low, and time is an issue. In the United States, construction of a nuclear plant takes at least a decade or two from initial planning to licensing and operation.
Renewable alternatives
On the other hand, renewable energy sources - biomass, wind and solar - have attractive advantages. According to the Union of Concerned Scientists, biomass "supplies almost 15 times as much energy in the U.S. as wind and solar power combined - and has the potential to supply much more."
Fermentation, the process of making alcohol, is a big item on the Great Plains, where corn is being converted into ethanol and mixed with gasoline. A 2002 U.S. Department of Agriculture study found that the energy one can recover from ethanol is only a small amount greater than the energy needed to produce it, but research breakthroughs may change this situation.
Wind energy is increasingly competitive with fossil fuel-generated electricity. According to the American Wind Energy Association, "State-of-the-art wind power plants can generate electricity for less than 5 cents/kWh with the Production Tax Credit in many parts of the U.S., a price that is competitive with new coal- or gas-fired power plants." Meanwhile, according to the website Solarbuzz, solar energy costs need to drop from the present 30 cents per KWh to around 10 cents per kWh, "which would allow solar technology to compete more strongly with other renewables and capture a significant share of the electricity market."
Unlike biomass or fossil-based energy systems, the exciting thing about wind and photovoltaic energy (direct conversion of sunlight to electricity) is that there are no fuel costs whatsoever. Both wind and solar generally pay back the energy used to create them in a just few months; turbines and collectors can be erected incrementally, on an as-needed, pay-as-you-go basis.
Accelerating innovation
At Research Corporation for Science Advancement, the science foundation that I lead, we have chosen to begin the first round of a new major research funding program around solar power.
The program, called Scialog ("science" and "dialog" combined), seeks to jumpstart major breakthroughs in the science and technology underlying issues of high national importance with an initial focus on the conversion of solar energy to electricity and fuels. It will provide catalytic funding to early career scientists in U.S. academic institutions who are proposing high-risk/potentially high-reward research that has the potential to make transformative advancements in the efficiency, durability and cost of solar energy conversion systems.
This $8-million-plus, three-year first round of Scialog represents a bold experiment by RCSA and its current partner, Science Foundation Arizona, to accelerate the pace of scientific innovation. The aim is to assemble collaborative research teams and connect them with resources from government, private enterprise and foundations to bring the latest discoveries in research to fruition in new solar technologies and industries.
Caltech's Nate Lewis, chair of this first-round of Scialog, has said that solving the world's looming energy crisis is the most important thing we humans can achieve, because so much of who we are and what we hope to become is dependent upon ensuring adequate sources of energy. At RCSA, we agree. We also believe that doing so without exacerbating global climate change and needlessly damaging the planet is a terribly important thing to get right.
The author is president and CEO of Research Corporation for Science Advancement (www.rescorp.org), America's second-oldest foundation, begun in 1912, and the first dedicated wholly to science.