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| | A major causes of pollution throughout the world is the extensive use of the internal combustion engine (ICE) to get us from A to B. The ICE is a major contributor to increased levels of carbon dioxide which is a major factor in global warming. It is also a major cause of high ozone levels in our cities, otherwise know as smog, and the resulting health problems. The automobile manufacturers and the oil companies have done, and are continuing to do much to cut the levels of pollutants that are being emitted by vehicles, and here in Los Angeles we have noticed this effort in the form of better air quality and fewer days where it has been unhealthful just to go out doors. The summer of 1999 has been remarkable as the first year when there were no first stage smog alerts in Southern California. While reduction in vehicle emissions was a major contributor to the lower smog levels, the principle reason was the cooler than normal weather this year. The average automobile pollutes in many ways. While the emission of carbon monoxide, carbon dioxide and a variety of hydrocarbons is the major cause of air pollution, there are several other forms of pollution that also contribute to the problem. Even the ultra low emission vehicles (ULEV) that are about to appear on the market are going to eventually pollute in many of these ways. When a vehicle is new, it tends to run fairly clean and does not cause much pollution other than tail pipe emissions and hydrocarbons that evaporate from the fuel tank while the vehicle is parked. Hydrocarbons are also released into the air when we fill our gas tanks. If you don't believe me, take a sniff next time you fill up. Don't breath too deeply though as the vapors leaking into the air contain several known or suspected carsinogens. Topping off the tank also tends to cause fuel spills that will evaporate quickly and add to the hydrocarbon levels in the air. As the vehicle begins to age, other systems will eventually start to wear and create additional pollution problems. Wear in an ICE as it ages causes the cylinder to become slightly oval in shape. This results in the ability of oil to pass beyond the piston rings and burn along with the gasoline when ignition occurs. This results in an increase in the amount of pollutants that the engine produces. You will notice as your car gets older that you occasionally need to add oil to the engine between oil changes. This could be a result of your engine burning oil. Eventually this will get so severe that your car will fail its smog test and need repair. The engine will begin to leak small amounts of oil as the seals around the oil pan begin to age. Most of this oil is going to end up on your driveway but a significant amount will leak onto the roads. When it rains this oil floats to the surface and make driving much more hazardous. The effect are particularly bad in dry areas like Los Angeles where slick conditions cause increased accidents, brings traffic to a crawl, and generally makes commuting a misery. Eventually, the oil finds its way into storm drains and into the ocean. Most car engines are liquid cooled. While we usually think of these engines being cooled by water, what we actually put in our cooling systems is ethylene glycol. As vehicles begin to age, cooling systems develop leaks, depositing ethylene glycol onto the road. Now ethylene glycol apparently tastes sweet but is highly toxic. Animals drink the coolant and die. The death of at least one of the California Condors released into the wild from LA Zoo has been attributed to drinking ethylene glycol. Of course, when it rains the coolant is washed into storm drains and then into rivers and the ocean increasing pollution. The average vehicle on the roads of California is ten years old so the likelihood of leaks and increased emissions due to engine wear is high. If everyone drove a brand new ULEV the pollution problems would be much less, but most people cannot afford to change there car every two or three years. Right now, the only type of vehicle that is classified as a zero emission vehicle (ZEV) is the battery powered electric vehicle (BEV). The critics of the BEV like to point out that these vehicles pollute just as much as an ICE but do it in different ways. One contention is that the BEV does not reduce pollution it just shifts it from the tailpipe to the smokestack. A recent study came to the conclusion that a major move to electric vehicles would actually increase pollution. This study assumed one million vehicles on the roads being charged during the day. The resultant increase in energy requirements would be met by building more coal or oil fired power stations. The reality is that most electric vehicle charging takes place at night when surplus energy is being wasted because it is inefficient to shut down existing power plants when demand falls at night. Here in California, to meet the growing need for power, we need to develop alternate forms of electrical generation. As an example, at the Santa Monica City Hall they have a charging station that can accept up to seven vehicles. This charging station works from solar cells during the day then switches to the electric grid during the night.
Pictured at left is the solar power generating unit at Santa Monica City Hall. Using clean solar energy to charge an EV makes them true Zero Emission Vehicles. A study conducted by Carnegy Melon university came to the conclusion that the introduction of BEVs in the Los Angeles area would increase pollution caused by lead. The study assumed 500,000 BEVs on the roads of LA all being powered by lead acid batteries. The pollution would be caused by the lead lost to the environment when batteries are recycled. This study was flawed in two ways. First it assumed that the loss rates for lead during battery recycling would be at the national average. This average is much higher than the amounts of lead that are allowed into the environment from the recycling plants in California. This in turn produced a pollution count much higher than would actually be experienced if we recycled all those batteries. Another major flaw was the assumption of lead acid batteries for all those vehicles. Most of the major vehicle manufacturers do not install lead acid batteries on their vehicles. Toyota and Honda use nickel metal hydride (NiMH) batteries while Nissan uses Lithium Ion batteries. GM's first generation EV1 did use lead acid batteries and they will be an option on the generation II machines due out soon. However, the vast majority of the new EV1s will have NiMH batteries. Ford, Chrysler and Chevrolet are also switching to the NiMH batteries for their electric vehicles. Only the smaller manufacturers like Corbin and AC propulsion are still exclusively using lead acid batteries and they can be expected to switch as prices for the new technology batteries begin to fall. Now check under the hood of your trusty ICE and you are going to find that it uses a lead acid battery. If we begin to replace these cars with NiMH or Lithium Ion batter powered BEVs, then we will actually reduce the number of lead acid batteries being recycled and so reduce lead pollution. I believe that the widespread use of BEVs would greatly improve air quality. As an added bonus, it would reduce our dependence on oil imported from areas of the world that can be best described as unstable. It will also put off the day when supplies of this non-renewable resource begin to run out. It is important however that as demand for power increases, we meet that demand by the addition of more power plants that use renewable, non-polluting energy sources. |
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