[The Vector] Vehicles and Energy 101
As transportation takes the lion’s share of our oil consumption, illustrated in the chart here (compliments of WTRG Economics), it is worthwhile clarifying some of the various terms defining innovations and types of vehicles you may see, which we will write about in Vector.
- Alternative-fuel vehicles do not burn gasoline – they are powered by other sources such as electricity, propane, ethanol, etc.
- Fuel-flex vehicles run on gasoline and another source, such as ethanol.
- Hybrids combine two propulsion systems, typically electric with a gasoline or diesel engine that acts as a generator when the battery runs low. Often these cars are referred to as Plug-in Hybrids due to the electrical system that is charged by plugging in to the electrical grid.
- EV or Electric Vehicle refers to pure electrical vehicles.
A short summary of fuel types:
- Biodiesel has been a grass roots oil replacement, but there are issues when used in lower temperatures (it thickens and needs an additive). Typically biodiesel is biodegradable (depending on the source), it releases 75% less carbon, and can be used in diesel engine vehicles, but can smell quite bad. However, depending on the source, it may or may not be good for the climate or the environment. For instance, imported biodiesel derived from palm trees of the Brazilian rain forests was found by the European Union to be twice as bad for global warming than petroleum diesel. Most biodiesel companies are outside the U.S.
- Natural Gas is mostly comprised of methane, burns cleaner than other fossil fuels, and is cheaper. Natural gas is also plentiful in the U.S., and many (like T. Boone Pickens) have been advocating for conversion of large trucks and fleet vehicles to natural gas – vehicles in which electric or other alternative fuels would not be strong enough. Pickens believes we can reduce oil imports dramatically, increase jobs, boost the natural gas industry at home and enhance energy security by carrying out a conversion plan and has supported several legislative plans on the dockets now. Congress will soon be considering H.R. 1835 and Senate Bill 1408 which address the issue of using natural gas for large vehicles.
- Propane is the most used gas alternative in the U.S., including more than 200,000 fleet vehicles. It is a by-product of natural gas, but many say a downside is the exhaust is polluting and prices are too similar to gasoline (unlike natural gas.)
- Ethanol has been a favored fuel used by Midwestern farmers and others. It is usually corn-based in the U.S., mixed with gasoline and used in fuel-flex vehicles. While there are more than an estimated 2.5 million fuel-flex vehicles in the U.S., only a small portion actually use ethanol because it is not widely available. I am not a fan of corn-based ethanol. 99% of corn is fertilized by products made from fossil fuels; corn erodes soil 18 times faster than it can reform; a gallon of ethanol requires 785 gallons of water (says an Arizona State University study in 2007) while a gallon of gas takes 2.5 gallons of water; it takes a lot of energy to produce ethanol; increase in corn prices from ethanol demand can spill over to the food supply, which affects grocers, farmers, consumers (meat and poultry prices can increase); and this can affect poorer countries who need corn.
- Hydrogen is an end-product that needs much energy to make it, and there are technical challenges in making, storing and transporting it. The U.S. Dept. of Energy had been a proponent of hydrogen for a while, but there are few hydrogen-filling stations and it has seemed to lose momentum. Hydrogen fuel cell cars are available on a limited basis – fuel cells depend upon a chemical process (using hydrogen and oxygen) to supply power as opposed to batteries that are recharged with electricity.
- Battery power used to complement gasoline engines (plug-in hybrids), or pure battery cars (EVs), seem to be the most feasible and have garnered much support and promise. Public demand for the Prius has exceeded expectations over the last few years, and a number of carmakers are getting on the bandwagon. Obviously, the more renewable energy can power electricity, the better for the overall picture since electricity use could increase to charge the batteries. Advances are being made in research and development of batteries, which should help progress this type of vehicle. Critics usually cite that a charge length is not good enough for all drivers, but if the typical driver commute is less than 35 – 40 miles per day, it is feasible. There is need for charging stations and infrastructure, of course. Solar powered battery-electric cars are another, cleaner option.