(This is Part 6 of a series. Go back to Part 5.)
1d. Reducing carbon emissions
The world is not running out of oil. It is running out of cheap, easily accessible oil. If we count Canada's oil sands, Venezuala's heavy oil and other reserves, the world has enough oil for at least a few decades.
The problem is that the oil is getting harder and harder to access. The low-hanging fruit was exploited a long time ago. Now, in order to find new oil, oil companies are having to drill much deeper and in much more hostile climates, such as deep water drilling or politically volatile areas. And in spite of this intense effort, discovery of new oil fields peaked decades ago and has been declining ever since.
Another way of saying this is that oil is becoming more expensive, not just in terms of money, but even more important, in terms of energy return on energy invested (EROI). That is, it takes a lot of energy to extract the energy locked in oil tars, oil sands, deep water drilling and so on, and that increased energy investment reduces the energy return.
Natural gas is cleaner than oil but will also face the same problems as oil—declining discovery and production coupled with increasingly difficult and expensive extraction. Hydropower is a good way of generating electricity, but it's been developed already. There simply isn't very much additional hydropower that can be brought onstream. Not to mention that hydropower is dependent upon a resource—water—that will probably be as scarce and valuable as oil one of these days.
Nuclear power has its own problems, first of all that it creates huge amounts of nuclear waste that nobody knows what to do with. Not to mention that fission reactors can produce uranium and/or plutonium—used in nuclear bombs—thus worsening problems of potential nuclear proliferation into dangerous hands.
Biofuels are all the rage now, but are they really a good solution? It seems to me that the biggest drawback to biofuels is that their EROI (energy return on investment) is so low. By the time you count all the energy that went into planting and growing and fertilizing and distilling the plant and so forth, you're getting back not much more energy than you put in. Additionally, it's using up resources—fresh water and good cropland—likely to be increasingly scarce on a heat-stressed planet.
Alternative energy is surely the wave of the future, but it will still play a marginal role for at least the next couple of decades. For one thing, it is still considerably more expensive to produce than energy generation from fossil fuels.
More important, however, is the fact that these technologies will take considerable time to scale up. For example, to provide the electricity currently generated in the United States, wind power generation would have to increase by approximately 80 times. To do the same thing with solar power would require an increase of approximately 1400 times the current solar power.
A consideration of such tremendous numbers suggests the conclusion that solar, wind and so on will not be able to come anywhere near to replacing our current fossil fuel usage anytime soon. Alternative energy will be an increasing player, certainly—but still a marginal one—for some time to come.
For these reasons attention is increasingly turning to coal. One of the interesting things about coal is that there is lots and lots of it. It's estimated that there is enough coal in the world to supply the planet's energy for at least a century and possibly two. Moreover, coal is located abundantly even in areas that possess little other fossil fuel, such as Germany or South Africa. The U.S. possesses 27% of world reserves.
The problem, of course, is that coal is extremely high in carbon and pollutants. An electrical generating plant running on coal is giving off twice the carbon dioxide of a plant running on natural gas—not to mention many times the amounts of sulfer, particulates, nitrogen oxide and so on. A car running on synfuel made from coal, because of the tremendous energy that went into making that fuel, is effectively giving off twice the carbon dioxide and pollutants as a car running on gasoline.
Nevertheless, because of good supply and because coal is relatively cheap, it's estimated that coal consumption will increase by 71% in the next 25 years. Coal-fired generating plants are being built at a fantastic rate all over the world. For example, the U.S. plans to build 153 new plants in the next eight years. The Chinese are building the equivalent of a giant 1000 megawatt coal-fired plant every week.
Of these hundreds of plants being built, only a handful are planning to reduce the carbon dioxide that will be spewed into the air. This must change, and soon, because otherwise it will be almost impossible to prevent the carbon concentration in the atmosphere from reaching
triple the pre-industrial concentration. That is a level where the planet would almost certainly be experiencing widespread crop failures from extreme global heating.
Pollutants such as sulfur, mercury and particulates are, more and more, being removed from the exhaust of coal-fired plants. This isn't terribly difficult to do. The real problem is carbon dioxide—preventing the large amounts of CO2 given off by the burning of coal from entering the atmosphere.
The key to using coal, thus, lies in finding ways to sequester the carbon dioxide given off from coal combustion so it doesn't enter the air. The best approach to doing this so far is called "integrated gasification combined cycle," or IGCC. In this process coal is not directly burned but rather turned into a gas first and then burned. This allows for much easier separation of the carbon dioxide so it can be sequestered.
An IGCC coal plant is currently 15-20% more expensive to build than a conventional one, which is why IGCC aren't generally being built. This is an area where the governments could and should step in to provide strong financial incentives for the building of IGCC plants.
Recently the Intergovernmental Panel on Climate Change, a UN body of worldwide scientists, estimated that 2 trillion tons of CO2 could be stored in old oil and gas wells and other geological formations. That is about 80 times the current global output of carbon dioxide, so ample storage for CO2 sequestration would seem to exist.
The single most important measure for encouraging various energy efficiency and green technology efforts, including the building of IGCC plants, is to put a price on carbon, either in the form of a tax on carbon or in the form of a cap-and-trade system for carbon emissions, or both.
A market in carbon-emissions trading has begun in Europe, and several northeastern states are starting one in the U.S. According to estimates, an inital price of $100-$200 a ton should be enough to encourage IGCC plants. What has been missing so far is political will at the federal level to implement this and other necessary measures. In my opinion, what is needed most now is courageous and farsighted political will.
(This is the end of Part 6. Go to Part 7.)
—jim sloman, for 12.11.06
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