Ben Cipiti, Sandia National Laboratories
December 24, 2007 | 53 Comments
For the past thirty years our country has become increasingly more aware of the effects our energy use has on the environment. At the same time, it is clear that our dependence on foreign oil is having significant consequences to our economy and our national security. Yet despite alternative technologies, we still get most of our energy from the fossil fuels. We know we have a problem, but the challenges of moving away from the established technologies and infrastructure are monumental.
Many of us want to know what we can do to make a difference. Yet with so much varying information about energy alternatives, it has become difficult to choose which technologies really make sense and which will be a waste of research dollars. We have become skeptical of anything that the so-called "experts" tell us — and rightly so as many of the experts have their own motives.
The use of ethanol is the best example. The major criticism of ethanol revolves around the excessive energy inputs required to grow, harvest, and convert corn or other crops into fuel. A number of studies are available that show a slight net energy gain and a slight decrease of pollution with ethanol use. (see http://www.transportation.anl.gov/pdfs/AF/265.pdf) But if we then find out that those studies were funded by the Department of Agriculture, we have to question the work. Other studies written by those without a special interest show a net energy loss with the use of ethanol and a pollution increase compared to oil. (see http://petroleum.berkeley.edu/papers/Biofuels/MyBiofuelPapersTop.htm)
It has become surprisingly challenging to find truly un-biased studies. Researchers are always fighting for more funding, so they tend to paint their work in the best possible light — seldom is the entire story told. Clean energy options need to be examined from a number of perspectives including environmental impact, economics, the domestic resource base, public acceptability, and reliability.
If ethanol is not a net energy producer, and if there is no pollution difference from oil, then why should we head in that direction? Reducing dependence on foreign oil is an admirable goal, but even converting our entire corn crop to ethanol would only displace about 15% of our oil use. A great deal of money in the form of research dollars and subsidies has been poured into ethanol, but it will not achieve our goals of drastically reducing pollution and eliminating dependence on foreign oil.
Hydrogen has also received significant funding recently, but the hydrogen economy has many flaws that need to be considered. The technology for producing, transporting and using hydrogen in fuel cells is still a few decades off. Efficient production of hydrogen can only occur with very high temperature heat which eliminates all of the renewables except for concentrated solar. But the single biggest problem with the hydrogen economy is that it will be incredibly wasteful of energy resources (and very little attention has addressed this issue). Consider that hydrogen first must be produced in a power plant, and then the hydrogen gets converted to electricity in a fuel cell to power an electric motor. The overall process of producing, compressing, transporting and finally using hydrogen has many efficiency losses. Why not eliminate the middle man and go straight to electric vehicles?
It turns out that when compared side by side, an electric vehicle economy will be more than twice as efficient as a hydrogen economy. In other words, the hydrogen economy would require building twice as many new power plants as compared to converting to electric vehicles. And whereas hydrogen production only makes sense with high temperature nuclear or solar heat, the electric vehicle economy can use any source of clean energy — including all of the renewable technologies.
Electric vehicles are not without their share of difficulties. Battery technology still needs to improve, both in terms of performance and cost. But electric vehicles have a development path already established. The commercial success of hybrids is leading to cost decreases that will soon lead to the plug-in hybrid. With more widespread use of plug-in hybrids and with the emerging technology of rapid charge batteries, it is likely that we will soon see an all-electric vehicle that is desirable to a majority of the population.
Solutions to our energy problems do exist, but it will take a variety of technologies to reach our goals. Of the alternative transportation options, electric vehicles coupled with increased use of renewables and other clean sources of energy will be the most efficient way to reduce pollution and eliminate dependence on foreign oil. We need to look at all of the issues to concentrate funding on the solutions that make sense.
Ben Cipiti received his bachelor's degree in mechanical engineering from Ohio University and PhD in nuclear engineering from the University of Wisconsin-Madison. He currently works at Sandia National Laboratories in Albuquerque, New Mexico, with research interests in energy economics, fusion energy, the nuclear fuel cycle and nuclear material safeguards. He is also the author of The Energy Construct.