TCS Daily


TCS COP 10 Coverage: Our Low Carbon Future?

By Ronald Bailey - December 15, 2004 12:00 AM

BUENOS AIRES -- "To stop further damage to the climate we need a worldwide 60% reduction in emissions by 2050," declared British Prime Minister Tony Blair in February 2003. Setting aside the question of whether or not catastrophic climate change due to adding extra greenhouse gases (GHG) to the atmosphere is really likely, is Blair's goal feasible?

The World Business Council for Sustainable Development (WBCSD) released a report here in Buenos Aires at the United Nations Conference on Climate Change. It shows that achieving such steep reductions is probably impossible. The report assumed a goal of stabilizing carbon dioxide in the air at 550 parts per million (ppm) by 2050. The current level is 380 ppm. The report further assumed that the poorest people on the planet will want to enjoy the higher levels of prosperity that comes from economic growth fueled by access to energy supplies.

Presented by two oilmen, David Hone from Shell and Mark Akhurst from British Petroleum, the report outlines what it would take to attain those goals. They based their analysis on economic and GHG emission storylines devised by the Intergovernmental Panel on Climate Change's (IPCC) Third Assessment Report that assumed that carbon emissions would reach about 14 gigatons (14 billion tons) annually by 2050. Humanity currently emits about 7 gigatons of carbon (excluding traditional biomass burning of 1gigaton) annually in the form of carbon dioxide. Burning 7 gigatons of the current mix of hydrocarbon fuels produces about 22 gigatons of carbon dioxide.

To keep from building up carbon dioxide to more than 550 ppm in the atmosphere by 2050, no more than the current 7 billion tons annually should be emitted. Hone and Akhurst claim that the goal of doubling world energy supplies while emitting only 7 gigatons of carbon by 2050 can be accomplished using technologies now available.

Although they differ in some details, the WBCSD report relies a good bit on the analysis published in Science by Princeton University engineering professor Robert Socolow and his colleagues. Both use the concept of technological "wedges" which, when fully deployed in 2050, will result in 1 gigaton per year of carbon emissions reductions. Hone and Akhurst stressed that major technological transitions take a long time to implement -- there are no quick, easy and cheap ways to reduce carbon dioxide emissions. To illustrate the point they offer a scenario in which some type of zero emissions vehicle becomes available in 2010. Beginning with the deployment of 200,000 zero emissions vehicles growing at a very unrealistic 20% rate per year, it would take until 2050 before such vehicles outnumbered conventional vehicles.

As an outlandish thought experiment, Hone sketched out a scenario in which all new power generation facilities emitted no carbon dioxide from now on, e.g., use only nuclear power, renewables, and coal power that somehow sequestered the carbon dioxide by perhaps pumping it into empty oil reservoirs. When would carbon emissions begin to decline? In about 30 years. Why? Because the old power plants would still continue to emit before they aged out and were replaced.

Let's take a look at some of what it would take to achieve the WBCSD goal of stabilizing concentrations of carbon dioxide in the atmosphere over the next 50 years. First, new low carbon technologies would need to begin being deployed almost immediately. To reduce projected emissions by 1 gigaton per year in 2050, the world would have to build 1400 new combined cycle gas turbine 1 gigawatt power plants rather than coal fired plants. A gigawatt is enough electricity to power about 400,000 homes. That translates into a growth rate of 2.6% per year -- or building 2 new gas power plants per month for the next 50 years. The International Energy Agency projects a 2.4% rate of growth through 2030.

To avoid another gigaton of carbon emissions by 2050 would require building 700 1 gigawatt nuclear power plants rather than the equivalent conventional coal facilities. That means that the rate of growth in nuclear power generation needs to be 4 percent per year rather than the current 2.5 percent. One more gigaton of emissions could be cut if the world's projected 2 billion vehicles in 2050 got 60 miles rather than 30 miles to the gallon. Another could be curtailed by 300,000 5 megawatt wind turbines. Of course, the wind turbines would need to be deployed in an area the size of Portugal and 5 megawatt wind turbines are only prototypes now. Biofuels derived from 250 million hectares of high yield crops could avoid another gigaton of carbon emitted per year in 2050. This would mean that a sixth of the world's current cropland would be devoted to producing fuel. That can't be good for biodiversity. And building 700 coal-fired 1 gigawatt power stations using carbon dioxide capture and storage would cut 1 gigaton of carbon. Akhurst pointed out that no low-cost carbon dioxide separation technology currently exists and that carbon capture and storage facilities would be nearly the same size as the power plant. The remaining 2 gigatons can be avoided by a combination of increased energy efficiency in appliances and buildings, more mass transit, and some societal changes.

Finally, the WBCSD study included a possible fuel mix for the world in 2050 in which the world's power supply is doubled and emits 9 gigatons of carbon per year. In that scenario, the world will need the equivalent of 3000 1 gigawatt natural gas-fired power plants; 1000 1 gigawatt coal-fired plants; 1000 1 gigawatt coal-fired plants with carbon capture; 1.5 million 5 megawatt windmills; 2500 nuclear power stations; 2000 hydropower stations; 65 exajoules of solar power; 1 billion high fossil fueled vehicles and 1 billion biofueled vehicles; 50 exajoules of biofueled heating and cooling and 250 exajoules of fossil fueled heating and cooling. An exajoule is equivalent to approximately 23.5 million metric tons of oil.

Currently, humanity is fueled by 1000 1 gigawatt coal-fired power plants, 400 1 gigawatt oil-fired plants, 250 gas-fired plants, 350 nuclear power stations, 500 gigawatts of hydropower, 750 million fossil fueled vehicles, 130 exajoules for heating and cooling, 50 exajoules from the burning of traditional biomass.

Doing the math, in order to double the world's energy supplies over the next 50 years, the world will need to build, among other things, the equivalent of 2750 new 1 gigawatt natural gas-fired power stations, 1000 new coal-fired 1 gigawatt power plants with carbon capture, 1.5 million windmills deployed over a bit less than 300,000 square miles, 2150 new nuclear plants, 1500 new 1 gigawatt hydropower stations, not to mention new solar and biofuel technologies.

Recall that Blair and others are calling for emission reductions of 60% by 2050. That would mean that instead of emitting 7 gigatons of carbon in 2050 under the WBCSD scenario, the world would emit only 2.8 gigatons of carbon annually. As the old saying goes, it may be that "you can't get there from here."

Ronald Bailey is Reason magazine's science correspondent. His email is rbailey@reason.com. His book, Liberation Biology: The Moral and Scientific Defense of the Biotech Revolution, will be published by Prometheus Books in early 2005.


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