by Steve Clark, Founder of Citizens for Clean Energy 1989 (changed to the singular “Citizen” when no one seemed to care during the ’90s), now affiliated with Clean Energy Action
|Biofuels: alternative, or red herring?|
There are many easy sacrifices we could all make that would save energy and reduce CO2. Unfortunately, many of these things will only make the transportation system "less bad", while what we really need is to get "good and clean" if we are going to keep the planet habitable.
If biofuels can make operating our cars carbon neutral, are they the answer? Let's first look at the concept of an alternative fuel. If there were alternative fuels that were available in quantities of scale, with equivalent energy and available at a reasonable price, that is what the oil companies would be selling us. It doesn't exist. However, the problem with making personal transportation green doesn't lie with the fuel. It is the Internal Combustion Engine (ICE) that is the problem. We don't need another liquid to dump through an inefficient ICE vehicle. We need a "new" vehicle. Most people don't understand energy efficiency. I recently came across someone who claimed the ICE vehicle was efficient. He wrote, " . . . modern engines are already very efficient. The maximum effective efficiency of a Carnot cycle engine is around 75%, which many modern engines at least approach. If it still burns fuel, it can't get much more efficient than a small high-compression engine (ala turbo diesels or the like)." He is absolutely wrong. Mechanical efficiency is high, but thermal efficiency in an internal combustion engine is low. "For a heat engine operating between 300°C and 100°C, with a DT of 200 degrees, this maximum efficiency would be: Efficiency = 200/(300 + 273) x 100 = 34.9% (more on this here).
Thermal efficiency is the percentage of energy taken from combustion that is actually converted to mechanical work. In a typical engine, the thermal efficiency is only about 26%. Most engines are about 94% mechanically efficient. This means that for a stock production engine, only 20% of the power in fuel combustion is effective.
But, in the real world of stop-and-go driving, we are operating our vehicles at only about 10% efficiency. If you take it one step further and include the well-to-wheels analysis; with oil exploration, extraction, shipping, refining, military protection of oil resources and other externalities, and then consider that what we really want to move is our own 150 pound bodies (not the three-ton automobile), the efficiency is quite a bit short of 1%.
The point is that maybe we should first question the whole nature of the personal automobile. This is probably a step too far for the average person, but it might begin to give us an idea of what is possible. At present, there are several prototype vehicles that get in excess of 1000 mpg. They won't get the whole family and the boat to the lake, but they will provide for personal mobility most of the time.
Given the current state of the automobile, there is no possible way that biofuels will ever provide more than a small portion of the energy needed by such an inefficient technology. The real answer to the problem of the personal vehicle is not an alternative fuel – it's an alternative technology for moving vehicles.
That technology is finally becoming available: the electric vehicle (EV). EVs are 90%+ efficient. This solution is known as a convergent solution, one in which everyone who thinks about it eventually comes to the same answer. And there are some very smart and influential people who are creating the next generation of vehicles. Two examples are the Tesla Roadster and the Think Nordic. Even General Motors' executives have finally admitted they will have to cut their ties to the oil companies and take the car out of the environmental equation by changing to electric drives.
One way to think about efficiency is to understand that what you really want is mobility, not gasoline. Stop thinking in miles per gallon (mpg) and start thinking in Miles Per Dollar (MP$). If your car gets 30 mpg and gas is $3/gal, you are getting 10 MP$. An electric car can get better than 10 times that amount, or 100 MP$ at present utility rates, and even with dirty coal power it still cuts CO2 per mile driven. But now the possibilities get really interesting.
I recently read an article saying that solar electric panels or photovoltaics (PV) are a homeowner's hedge against future increases in the cost of electricity. By powering your EV with PV you have a hedge against gasoline, a much more volatile energy cost. You will never worry about any future increase in the cost of mobility. Sunshine falls on your roof, it is stored in your car and you get your mobility for free. You have eliminated the supply chain that brings you carbon fuel. We will never have to fight wars over the sunshine or worry that someone will restrict our access to the supply. This is an advantage you cannot get with any other transportation technology.
There are many other advantages to the EV, such as no oil changes or tune-ups, and no more car exhaust polluting the air we breath. Therefore, our communities will be cleaner and healthier places to live. As you can see, there will be some big losers when this technology becomes widely available. To everyone who wants to reduce their carbon emissions and leave a cooler planet for future generations, the benefits are undeniable.