There is no question that we need to wean ourselves off of fossil fuels. The argument has been driven by at least three distinct considerations: the increasing scarcity of fossil fuel resources, the geopolitics of oil, and the impact of fossil fuels on the environment. These very different motivations create the possibility of consensus for action among people with very different viewpoints but the evolving world of energy is making such consensus increasingly difficult to achieve.
Unquestionably, the most significant factor affecting the transition away from fossil fuels is that their scarcity turns out to have been highly overrated. Coal, which is used to generate over 80% of the world’s electricity, is plentiful in many countries. Many estimates measure our coal resources in hundreds of years. Natural gas, with the advent of shale gas extraction techniques such as hydrofracking, has become an abundant resource in many parts of world and is widely promoted as the bridge fuel to the future.
Even oil, for which dire warnings about “peak oil” have often been sounded, appears to be more plentiful than earlier thought. Enhanced recovery techniques, unconventional sources such as tar sands and shale oil, and even coal liquefaction, all add up to no real reduction in our supply of oil for a long time to come. According to the International Energy Agency, the United States will overtake Saudi Arabia as the world’s leading oil producer by about 2017 and will become a net oil exporter by 2030. We are hardly about to run out of oil in this country. That is good news on the geopolitical front but a complicated situation on the environmental front.
Meanwhile, coal is still by far the most plentiful and cheapest fossil fuel we have. For that reason, it is widely used here and abroad and its use is growing steadily. According to a study by the World Resources Institute, well over a thousand new coal-fired power plants have been proposed, the great majority of which are in China and, to a lesser extent, India. These countries have enormous populations that are making a rapid transition to modernization and, as a result, have rapidly expanding energy use that is largely being addressed by plentiful coal.
Unfortunately, coal is inherently more polluting and more carbon-intensive than other fossil fuel sources. Coal-fired power plants are, in fact, the largest contributor to the greenhouse gases associated with climate change. Oxford University professor of energy policy, Dieter Helm, persuasively makes the case in his published papers and his recent book “The Carbon Crunch” that the expansion of coal-fired power plants is the single largest problem driving global climate change and that unless it can be stopped, there can be no real progress in averting disaster.
The coal industry and its advocates invoke “Clean Coal” as the solution. What it refers to is the use of Carbon Capture and Storage – or CCS – to separate the carbon dioxide emitted in the combustion of coal or in coal gasification processes, capture it, and inject it into deep underground storage facilities or otherwise prevent it from entering the atmosphere. Such a process is likely to be costly and complicated, but coal is so inexpensive that one could spend quite a bit on CCS or other schemes for pollution control and it would still be affordable. The problem, however, is that CCS has not yet been developed on any sort of commercial scale or sound economic basis. Billions of dollars are being spent on ongoing research into clean coal technology, but as yet there is no consensus on when or even whether it can be widely implemented. In any case, it will not be ready to prevent the vast amount of additional emissions that would come from the new coal-fired power plants that are currently proposed nor does it reduce the emissions of existing coal-fired plants.
The discovery of abundant natural gas in shale formations in recent years has been hailed as a potential game changer for greenhouse gas mitigation. This is because carbon dioxide emissions from burning natural gas are only half of those produced by coal to get the same amount of energy. Dieter Helm argues that natural gas is the interim solution for getting away from coal until such time as renewable energy can take on the lion’s share of the load.
The potential for high-volume production of natural gas using hydrofracking and other modern techniques is not only seen as a way to move away from coal-fired power plants but is even proposed as a way to replace gasoline and diesel in cars and trucks. Natural gas already powers many buses and fleet vehicles (reducing carbon dioxide emissions by 30%) and represents an alternative to electric vehicles that avoids many of the current shortcomings of that technology. From the standpoint of carbon dioxide emissions from both power plants and from vehicles, natural gas really is a cleaner alternative.
More recently, however, natural gas is starting to be cynically described as a “bridge fuel to nowhere” because of the impact of methane leakage.
Natural gas is essentially composed of methane and extracting it always results in a certain amount of leakage into the atmosphere no matter how it is done. Hydrofracking in particular has an especially high leakage rate. The actual rate is not well known because the gas industry is not very forthcoming on the subject. Studies in recent years suggested that up to 4% of the methane produced in these gas fields leaks into the atmosphere. Additional reports of much higher leakage rates were recently presented at an American Geophysical Union meeting.
A number of studies in recent years have looked into the effects of this methane leakage from gas extraction on the climate. Tom Wigley of the National Center for Atmospheric Research was among the first to sound the alarm a couple of years ago on the impact of increased methane emissions resulting from high volume hydrofracking. Methane is a much more potent greenhouse gas than carbon dioxide. It remains in the atmosphere for far less time than carbon dioxide, but while it is there it is extremely effective at trapping heat.
These studies have seriously weakened the argument that natural gas can serve as a bridge fuel between coal and renewables. The idea has been that natural gas can serve as a primary fuel for perhaps 50 years or so until such time as renewables are sufficiently plentiful and economical. Models have shown that reducing carbon dioxide emissions by replacing coal with natural gas reduces the rate of climate change over the long term (i.e. 100 years). However, it is essential for such models to take into account the methane leakage problem. Because of the relatively short lifespan of methane in the atmosphere, it is important to look at the impact on climate over a time period of perhaps 20 years rather than a century. Models based on leakage rates from 3 to 8 percent yield the net result that for even the low end of the range, global temperatures actually rise faster when coal is replaced by natural gas extracted by hydrofracking. Substituting natural gas for coal may reduce carbon dioxide emissions, but it might actually accelerate global warming.
There may be ways to dramatically reduce methane leakage in natural gas extraction, but the potential problem has to be acknowledged and made a high priority. One can draw analogies between coal’s problems and those of natural gas, but the differences are important. In the case of coal, there is an unwanted byproduct of its use (carbon dioxide) that is escaping and that somehow has to be captured and stored out of harm’s way. In the case of natural gas, it is the fuel itself that is escaping so that if it can be captured, it can just be sold for a profit. There is not an unwanted waste product to deal with. Perhaps that makes the problem less burdensome for the industry.
Clearly, the continued use of fossil fuels involves many tradeoffs. Clean coal technology could alter the equation completely if it becomes available but the growing use of coal is not waiting for that to happen. Hydrofracking presents multiple potential problems with respect to water contamination and air pollution as well as methane leakage. All of these problems have to be dealt with successfully in order for hydrofracking to be a sensible technology. These technical problems require technical solutions, not political solutions. Clearly, the stakes are very high.
All the issues facing the continuing use of fossil fuel share the common feature that the amount of money at stake is huge and there is a constant struggle between maximizing profits and mitigating effects on the climate. There is much talk about making money by going green, but cleaning up fossil fuel emissions is not cheaper than allowing them to escape. Industry has to be forced to clean up their act. Left to their own devices, they will put off until tomorrow the emission-reducing activities that they can implement today.
The abundance of fossil fuel resources leaves us in the position that governments around the world have to use their coercive powers to steer fossil fuel use in the right directions. Energy policy, regulation and monitoring may be unpleasant to many but without them, there is little chance that we will make any real progress on climate change.
From a climate perspective, the “right answer” is to eliminate fossil fuel usage entirely and go straight to renewables. Unfortunately, this is not yet a practical strategy. The major renewable technologies of wind and solar power are both intermittent in nature and cannot address all the needs of the grid. At least they can’t until a viable energy storage technology is available on the required scale. The changeover to renewables can’t happen fast enough to avoid the consequences of the world’s growing energy usage. We are stuck with fossil fuels for some time to come. It is easy to say that we simply cannot afford to keep using fossil fuels the way we are, but it is an entirely different matter to ask people to drastically reduce their energy use in the meantime to address climate change.
The path to reducing our carbon emissions is a difficult one. There are no simple solutions. Each “silver bullet” that we find has consequences that are not necessarily ones that we want. The collected wisdom of the energy community for quite some time has been that we need to do many things at once to combat climate change because only the cumulative effect of multiple efforts can make a real difference. No one thing can solve the problem and there is no truly painless solution. Perhaps if there can at least be consensus on that much, we can get on with what needs to be done.
Randy Simon has over 30 years of experience in renewable energy technology, materials research, superconductor applications, and a variety of other technical and management areas. He has been an officer of a publicly-traded Silicon Valley company, worked in government laboratories, the aerospace industry, and at university research institutions. He holds a PhD in physics from UCLA. Dr. Simon has authored numerous technical papers, magazine articles, energy policy documents, online articles and blogs, radio scripts and a book, and holds seven patents. He also composes, arranges and produces jazz music. He can be reached by comments to this blog or privately through Member Email.