Saturday, August 25, 2007

Hybrid Cars versus Electric Cars: Vying for Green Credentials?

The “Two Major Roads” that lead to a more environmentally friendly motoring are clamoring for our votes, which one will win and which one will you vote for?

By: Ringo Bones and Vanessa Uy

The two emerging technologies that serve to power a new generation of environmentally friendly cars – namely “hybrid power plant cars” and “pure electric powered cars” – are now clamoring to prospective customers who vote with their wallets and / or checkbooks. Marketing success hinges more on which of the two technologies –hybrid cars or pure electric cars - will be adopted by the major auto- makers. Irreproachable “green credentials” is now a major issue that determines which of the two will sell, and to a more or lesser extent; simplicity of operation and running costs. So here are the merits and faults that accompany the two different technologies.

Ever since the conspiracy theory surfaced to the mainstream media surrounding the “demise” i.e. product recall of GM’s EV1, interests on this sort of technology is in vogue again. The theory states that General Motors was under behest by the “1996 Republican Majority Congress” in collusion with “Big Oil Companies” to “kill” the EV1 because it’s “miraculous” performance could end America’s dependence on “Middle Eastern Petroleum.” Back in 1996, GM’s EV1 was the first pure electric car produced in commercial quantities by a major automobile company. It had pretty good credentials under its belt despite being powered by heavy and “inefficient” lead-acid batteries that could pose it’s own environmental problems. Fully charged, the EV1 has a range of 65 miles.

A lot has happened since then, today, a car that was referred to as the spiritual descendent of the EV1 is the TESLA Roadster. The TESLA Roadster is made by TESLA Motors a small automotive start-up company in San Francisco, California. One advantage that the TESLA Roadster has over GM’s EV1 is weight – or the lack of it. The TESLA Roadster is constructed out of carbon fiber that’s modeled after the Lotus Elise so it’s five times lighter than ordinary steel cars and also five times stronger due to the carbon fiber construction. The TESLA Roadsters claim to fame is it’s advanced lithium ion / lithium polymer battery that’s not only several times lighter than the one’s used in the EV1, it is also more efficient allowing the TESLA Roadster to have a 250 mile range on a single charge. Because of the carbon fiber construction and lithium batteries, the TESLA Roadsters high power –to – weight ratio allows it to accelerate like a high- end conventional internal-combustion-engine-powered-gasoline-fueled racecar.

In the other camp, hybrid cars i.e. cars whose both powered by a fossil-fueled internal combustion engine and storage batteries that drive the electric motors, are now on an uphill battle to gain “green” credentials. The environmental merit of hybrid cars is that the internal combustion engine can be made smaller than that of “conventional” cars because it’s primarily used to recharge the batteries, thus generating lower emissions of carbon dioxide and other pollutants. Hybrid cars also have better “mileage” than “conventional” cars because only in demanding situations i.e. going uphill and/or when quick accelerations are required that the two power plants is used in conjunction with each other. The most famous and highly advertised make/model of a hybrid car is the Toyota PRIUS.

While hybrid cars are praised because theoretically they could never ran out of “juice” while on the road due to the current ubiquity of gas / petrol stations over electrical charging stations. Pure electric cars – especially ones using the latest generation of lithium ion batteries – have better performance due to their high power –to – weight ratio compared to current hybrid cars. Also -if major auto makers will start mass producing them again- pure electric cars have the advantage over hybrids in terms of environmental friendliness because it’s much easier and cheaper to place air pollution mitigating devices at the power plant as opposed to every tailpipe of every car that’s running. Borrowing from the “transistor- principle” that a system with fewer moving parts is less prone to breakdown. Pure electric cars has this advantage because it uses only simple electric motors as a primary “engine” as opposed to the hybrid car that still has a conventional internal combustion engine with an inherently inefficient –in energy terms- clutch and gear drive systems. Also pure electric cars can easily tap electricity that’s produced from sustainable and / or non-carbon dioxide generating power plants like wind farms, solar photovoltaic power plants, fuel cell based power plants, etc. Also in the not-so-distant future, carbon offsetting might be legislated to include the transportation sector. Your carbon dioxide generating hybrid car could be singled out by the taxman in the coming years. Also, hybrid cars have “dubious” resale value as reported by Jeremy Clarkson in the 2003 – 2004 season of “Top Gear” an automotive TV show reviewing budget and high-end cars. On one episode, he advises against buying a hybrid car and to choose instead on a conventional car with a better mileage because this fuel- efficient conventional car is not likely to end up lying idly on some junkyard compared to the “hybrid” competition.

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