ALT-13 Alternative Fuel Sources
In the 1970s we faced high fuel prices and run-away pollution. Alternatives were explored, but fuel became cheap again and Americans once again turned to large, heavy and inefficient vehicles. Now prices are rising again and with them a new threat- global warming. It's time for change, and this time it's happening. We are increasingly seeing Hybrid vehicles, electric vehicles and the use of bio-diesel. The long-overdue clean-up of conventional diesel fuel means that we may at last start seeing ultra-efficient European diesel vehicles with milage comparable to the current generation of Hybrid vehicles on American streets.
Other solutions, like telecommuting and increasing the availability and efficiency of public transit systems, are the key to the future in the long term but we have to face it; Americans are not going to give up their cars any time soon. The flexibility and freedom offered by private vehicle ownership and the fact that since the end of WWII we have designed our communities around the idea that everyone will have a car will dictate our future for at least the next few decades. So what are the options?
LSVs- Low speed VehiclesThese are vehicles capable of road speeds up to 25 mph designed to be driven in local communities for shopping, errands and the like. They range from glorified golf-carts to small autos carrying 2-4 passengers. They are electrically powered and typically have a range of 20-40 miles. The advantage of these is that they can be very light weight as they are not subject to the same safety restrictions as normal road-going vehicles. They also use conventional, off-the-shelf technologies. The disadvantages are that they do not include many of the features of 'real' cars, have very limited range and speed and are restricted to use on roads with speed limits of no more than 35 mph. They are also relatively expensive, easily costing as much as a gas-powered sub-compact.
All-Electric DriveBattery-powered vehicles come in a variety of shapes, sizes and levels of performance. They share many of the problems of LSVs. Usually they have limited performance and a useful range of under 50 miles. If you live in a cold climate this will be made worse by the need to run a heater. A new trend is towards cycle-cars; three wheelers. In most states these are technically classed as motorcycles, allowing them to by-pass many of the safety standards of conventional cars so they can be made lighter and thus more energy efficient. Many of these Light Electric Vehicles have a limited top speed of 40-50mph, but they cost no more than an LSV and are much more versatile. Electric vehicles like the Tesla offer good range (up to 200 miles is claimed) and 'real-car' performance but are extremely expensive in part because of their use of hi-tech battery packs that use expensive materials in their construction. Capacitor-based storage systems from companies like Ireland's EEstor offer real hope for all-electric cars. They use fewer exotic materials and have enormously greater storage density. Ranges of 300-600 Miles per charge may be attainable with these systems but they are still several years away. The other problem is the electricity that these vehicles use has to be generated some where. If we are forced to rely on current infrastructure this simply means that we will be exporting the pollution from the cars to the power stations.
Gas-Electric Hybrids and 'Plug-in' HybridsThe best short-term solution that is already on the market is the Hybrid. These are gasoline-powered vehicles that use an electric motor to 'assist' the conventional motor and increase mileage. The best of them also have a continuously-variable transmission so that the motor mostly runs in it's most efficient power-band. The Toyota Prius is the best-known of these. Many owners will 'hack' these vehicles allowing them to run as all-electric vehicles for short journeys and be plugged in to household current to recharge the battery pack. Inevitable manufacturers will begin offering vehicles with this sort of operating cycle, increasing the cars usefulness and fuel economy while lowering emissions. GM has introduced a new plug-in hybrid concept- the VOLT. This is a plug-in hybrid that is primarily an electric-drive vehicle with a high-efficiency gasoline powered generator on-board to recharge the battery-pack in motion. This differs from conventional Hybrids in that there is no direct connection between the gasoline engine and the driven wheels. Drive is all-electric all the time. This offers all-electric drive for shorter trips, and for slightly longer trips can offer fuel economy up to 150 miles per gallon. Trips of up to 600 miles are reported to return mileage comparable to current conventional Hybrids. The car can be plugged in to recharge or placed in charge mode while stationary to charge from the 12 gallon tank while not being driven. If allowed to come to the market this type of hybrid offers the best and most practical solution for lowering emissions and increasing mileage. Currently it is configured to run on regular gasoline and E85, but future versions may run on other fuels such as bio-diesel.
Fuel CellsCrash-certified fuel cells for automotive use are beginning to be produced. These use hydrogen in a catalytic reaction to produce electricity. The exhaust they emit is water vapor. Fuel cell powered vehicles use all-electric drive and emit no CO2 or hydrocarbons. The draw-backs? They cannot see wide-spread use until a hydrogen-fueling infrastructure is in place, which will most likely take decades. Also- consider the effects of all these water-vapor emitting vehicles in crowded urban centers like LA. They will actually noticeably increase the relative humidity and cause a different sort of climate change in these areas. Also- producing hydrogen takes energy that has to be generated somehow so they have the same problem of 'exporting pollution' that other all-electric vehicles have.
Air-powered cars and HybridsA French company has developed and engine that runs on compressed air. A compressor uses an electrically-powered piston engine. Air is sucked into the cylinder, compressed by the piston and released into a storage tank. The French air-powered engine runs like a compressor in reverse. High pressure air from a storage tank forces the piston to move in the same manner that a burning mixture of fuel and air forces the piston to move in a conventional internal-combustion engine. The decompressed-air then exits the exhaust pipe. Power is provided by high-pressure storage tanks underneath the car. To refuel the car is either plugged in to a high-powered air compressor to refill the tanks, or is plugged in to household current so that an on-board compressor fills the tank. Performance of the prototypes is comparable to current electric cars, and hybrid-drive systems are envisioned for longer trips. Fuel/air-drive and electric/air-drive hybrids are possible. While promising this system is not yet on the market and has many of the same problems as electric vehicles, but it has some advantages too. For example the 'air engine' can run an alternator so running accessories has a much lesser effect on the car's range. Time will tell if the merits of this system will allow it to be viable in the market.
These are a few of the alternative-fuel options available, and they are short-term to be sure. The ultimate solution is to re-engineer our society and infrastructure to the use of mass-transit, but a paradigm shift of this magnitude and expense will be a very long time coming. In the meantime alternative fuel vehicles offer some hope of slowing environmental destruction and reducing our dependence on foreign oil.
