Created on Friday, 23 July 2010
This week, I'll examine some of the current automotive technologies aimed at reducing our dependence on fossil fuels and that help reduce the harmful exhaust emissions generated by automobiles.
By far, the most successful and recognized application of "green technology" is the hybrid gasoline-electric vehicle. Many manufacturers have introduced hybrid models into their lineups. Others are fast-tracking new products to compete in this growing segment.
This hybrid design combines a fossil-fueled power train with an electric storage and propulsion capability. Modern hybrid models are designed to switch efficiently between battery-power and gas-power propulsion.
Generally, when gas power is being used, the batteries are automatically recharged. Some designs recover energy from friction when braking, and this, too, is converted to electricity and stored.
Another promising technology is the plug-in hybrid all-electric vehicle. Within two years, Nissan and General Motors (and others) are planning to introduce mass-produced, plug-in electric vehicles.
With a plug-in electric (which produces zero emissions), an onboard battery can be recharged by plugging it into a normal household current, or at a designated recharging station.
Until now, battery storage capacity has severely limited a vehicle's driving range. Recent breakthroughs in battery composition and design promise to solve this impediment.
This raises questions about the recharging facilities needed to accommodate mass acceptance of the technology. Such an infrastructure doesn't yet exist. Another concern is recharging time. Today's drivers may not want to wait for batteries to recharge, even for short periods,
Ethanol, produced from corn or sugar cane, is a fuel option that is slowly gaining traction. It is clean burning and, when blended with gasoline, improves octane and lowers tailpipe emissions. Most fuel sold in North America contains some ethanol, usually 5 to 10 per cent (E5 or E10).
Some manufacturers produce and actively market "flex fuel" vehicles that will run efficiently on E85 or blends of fuel, containing gasoline and up to 85% ethanol. Older vehicles can be easily and cheaply converted to run on ethanol-based gasoline.
In Brazil, 95 per cent of the automotive fuel consumed in that country is locally produced ethanol. The benefits include almost zero pollutants and no dependence on foreign oil.
Biodiesel fuel (made from vegetable oil or animal fat) is another technology that is being actively promoted as an alternative to traditional fossil fuels.
It can be blended with straight diesel fuel and serves to reduce carbon monoxide, sulfur dioxide and other pollutants. The two big advantages of biodiesel are that it's renewable and it produces longer engine life.
Perhaps the cleanest alternative fuel is hydrogen, which produces almost zero emissions. Many years of promising research have resulted in very limited applications of this technology; thus far, it is uneconomical for mass production.
Natural gas is another clean fossil fuel, which has been used for many years on some commercial vehicles and delivery vans. Once again, specialized refueling outlets are required.
Other investigations of green applications for the automotive world include solar, magnetic and even nuclear propulsion.
Currently, any discussions about alternative energy sources usually include the internal combustion engine (IC). This standard engine type has been around for more than a century, and I don't see it being replaced soon.
In future, the IC will continue to be adapted to use various types of fuel, or used in conjunction with another source of power (electric motor).
If the IC engine remains the standard engine type for most cars and light trucks for the foreseeable future, it would make sense that automakers would seek to improve the IC engine performance and its fuel economy.
In fact, most automakers are pursuing that goal, experimenting with hardware and software modifications that will eventually enhance IC engine performance significantly.