(Updated 8/4/09; Original 2/6/06). Everyone can make a difference in achieving energy independence and a more healthy future. Consider these ten technologies the next time you select a vehicle for your fleet or personal use. All ten are important to clean transportation.
The less weight that you carry the better the miles per gallon. If you use a big SUV like the GM Envoy XL 2WD, your official EPA mileage is 15/19. Your mileage may vary (as in less distance, more bucks). If you use a much lighter GM Chevrolet Cobalt M-5, your EPA mileage is an improved 25/34. Less weight requires a smaller engine which burns less fuel. In their book Winning the Oil Endgame, Lovins, Datta, et al. report: “A panel of the National Academies’ National Research Council (NRC) found that…applying traditional, modest, incremental improvements, including only minor reductions in weight and drag, mpg gains of 14 to 53% would raise prices by $168 to 217/mpg.” At today’s prices, the payback for a vehicle buyer is less than three years.
3. Tires With Low Resistance
One reason that I get great gas mileage with my Toyota Prius is that it uses low rolling resistance tires. There tires also work surprisingly well when we go skiing in Tahoe, driving (carefully) on snow and ice. You can improve mileage with your current vehicle by keeping the tires fully inflated, thereby lowering rolling resistance and increasing mileage.
4. Powertrain Efficiency
Manufactures have been improving engines and transmissions for over 100 years. Engines are now made with many improvements including improved timing, fuel mix, less resistance, and variable value timing. They continue to improve mileage with new engines that can shut-off valves when not needed. For example, the Honda Accord Hybrid’s V6 engine features a Variable Cylinder Management system (VCM) that can deactivate three of the engine’s six cylinders during cruising and deceleration. Also used is the continuously variable transmission (CVT) which closely matches the transmission ratios with the optimum rpm range of the engine for better fuel efficiency. Look for vehicles with better miles-per-gallon due to use of advanced powertrains.
Hybrids store braking, downhill, and extra energy in advanced batteries and then supply the energy to an efficient electric motor. As a result, a smaller internal combustion engine (ICE) or fuel cell is used and run less often. The result is a big savings in fuel and far less emissions. An added pay-off of many hybrids is that they are computer programmed to turn-off the engine when it idles too long, and then automatically restart it when needed. Auto Express reports that Toyota insiders have admitted to a new 100 mpg hybrid with lean-burn 1.8-litre turbo engine and efficient lithium ion batteries.
How Hybrids Work
6. Plug-in Hybrid
At a recent conference, Toyota President Katsuaki Watanabe spoke about his dream of building a car that could cross the United States on a single tank of gasoline. He spoke of the future potential of plug-in hybrids, without formally committing Toyota to build these as commercial vehicles. He did state that Toyota is increasing its research and development in plug-ins. My wife and I share two cars. On a given day, one of us never drives over 40 miles alone. With plug-in hybrids, one of us would travel all day on electricity from the grid that is stored in batteries. When we occasionally need range, a plug-in hybrid would automatically engage the engine if the batteries got low.
When you fill your current vehicles, the odds are good that part of the fuel mix is from plants rather than oil. Energy independence is moving forward. Most California gasoline runs cleaner because it includes 5.6% ethanol. Most new gasoline engines can support 10% ethanol without modification. GM and Ford are selling hundreds of thousands of vehicles which can support E85, a blend of 15% gasoline and 85% ethanol. Soon, most cars in Brazil will run on ethanol, reducing its dependency on oil and adding jobs to its sugarcane industry.
Diesel engines are the standard for heavy vehicles, such as trucks and buses. Biodiesel is a blend of diesel, which is processed from oil, and fuel from biological sources such as soy or food waste. Blends of 5, 10, and 20% biofuel are popular because they run in most current diesel engines. Look for wide use of B20 in heavy vehicles.
Natural gas helps achieve energy independence because it is not refined from oil. CNG burns cleaner than gasoline, ethanol and biodiesel. CNG is popular with cities and other fleets with low-emission programs. The next time you take a taxi at an airport, it may well be running on CNG. These vehicles get priority at airports. CNG is CH4. It is mainly hydrogen. In fact, most early adapters of hydrogen vehicles are CNG fleet owners.
Over 2,500 people daily ride hydrogen vehicles in California, using 8 hydrogen buses and over 130 hydrogen vehicles. Next time you are in the Bay Area or Palm Springs, ride on a hydrogen bus in-service at AC Transit, Santa Clara VTA, or Sunline. Hydrogen is used in fuel cells with the only emission being water vapor. It runs at near zero-emissions in advanced engines. Hydrogen fleets are cleaner than the vehicles they replaced. The 30-plus hydrogen fleets in California get their hydrogen from several sources including solar power electrolysis of water, delivered hydrogen from steam reformation of natural gas and onsite reformation. In the future, they will also get hydrogen from pipelines, waste hydrogen, biologically processed, and from wind.