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Diesel vs. hybrid

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    Diesel vs. hybrid

    LOS ANGELES – This fall, Mercedes-Benz and Volkswagen have both made noise with the launch of new, cleaner diesels that meet tailpipe emissions standards in all 50 U.S. states and Canada. Next year, Lexus and Toyota fight back with new gasoline-electric hybrids.

    At the Los Angeles Auto Show, VW barely had time to enjoy winning the Green Car of the Year Award for the diesel-powered Volkswagen Jetta TDI, before Lexus showed off the 2010 version of its RX crossover. The '10 RX lineup will include a new hybrid model that Toyota and Lexus officials say is far cleaner than any affordable diesel can possibly be.

    The battle between diesel and hybrid, to date mostly a minor skirmish with little head-to-head conflict, is about to become a major engagement.

    Diesel advocates, essentially German auto makers who have years of experience and research with the technology thanks to its popularity with passenger cars in Europe, say diesel is proven to work at reducing fuel consumption, while also delivering better performance – especially in highway driving where hybrids offer virtually no fuel economy or emissions benefit.

    VW's Green Car win in Los Angeles offered some significant validation for the latest diesels. At a starting price of $25,775, the base Jetta TDI wagon is a versatile and affordable family vehicle that delivers 30 to 35 per cent better fuel economy than the gasoline version. It is also nearly $2,000 cheaper than the base Toyota Prius four-door hatchback ($27,400) before provincial tax rebates are factored into the equation.

    The Jetta TDI, like the recently introduced BlueTEC diesels from Mercedes (e.g. the ML 320 BlueTEC) and the coming cleaner diesels from BMW, also meets current Tier II Bin 5 emissions standards. This is the standard required to sell passenger cars in U.S. states such as California and Vermont.

    But Lexus officials say their upcoming 2010 RX 450h hybrid, as well as the new Prius hybrid slated to be unveiled at January's Detroit auto show, will meet Tier II Bin 3 standards. For diesels to get that clean, manufacturers will be required to make significant investments in new diesel emissions technology.

    Toyota officials argue that as emissions standards grow more stringent and the spread between the price of diesel fuel and gasoline grows wider, diesels begin to make less and less sense – that the diminishing return delivered by even the cleanest diesels will eventually and perhaps even quite soon, make them a losing proposition in the marketplace.

    “Let's bring it down to its basics,” says Toyota Canada managing director Stephen Beatty. “The argument in favour of diesel has always been that it has high torque and great fuel economy.

    “The downside is that it's more expensive technology in conventional form than a gasoline ICE – internal combustion engine -- and it has a very problematic emissions stream. “High tech emissions controls address some of that, but all you get in the end is a vehicle that meets the dirtiest allowable standard in California for passenger cars.”

    Of course, Toyota has good reason to cast doubts on the future of diesels in Canada and the United States. Toyota does not sell a diesel passenger car model in either country and has, in fact, put most of its high-tech muscle behind hybrids.

    Still, it is unusual for officials from one car company to directly criticize the technology push of others. So it was startling to hear Beatty say, “I personally think that diesel's day is never going to arrive because of the changes in regulations, the (price) spread between gasoline and diesel and the cost of the technology needed to meet Tier II Bin 3 standards.”

    Beatty's argument is that diesel engines already cost about 10 per cent more to build than a regular gasoline engine for passenger cars. The added cost of the emissions technology required to meet tough regulations adds more cost on top of that. Even more stringent regulations, which he expects to see come under the administration of President-elect Obama, will add even more cost to diesels if they are to be certified in all 50 states and Canada.

    Meanwhile, he argues that adding more emissions technology could undermine one of diesel's advantages – performance – while also reducing fuel economy.

    “When you add advanced technology to diesel it doesn't add power. When you add hybridization, one of the key plusses is power,” says Beatty.
    Moreover, argues Beatty, with diesel fuel selling for about 20 per cent more than regular gasoline in Canada, diesel is on a path to becoming a less attractive alternative than hybrid.

    (According to MJ Ervin & Associates, regular gasoline this week in Canada is selling for $.83 a litre, while diesel for passenger cars is at $1.05 a litre. The spread is much higher in the United States.)

    “Diesels by their very nature are so dirty,” says Beatty. “So by the time you've finished adding layer after layer of new advanced technology on a diesel, you've not only added cost, but in some cases you are taking away from the basic performance of the engine.

    “By adding all that cost, you're not getting any increased benefit in terms of performance – unlike hybrid. With hybrid you take the vehicle that already has very, very clean emissions and you clean them up as much as 70 per cent more. With hybrid, you achieve better fuel economy and more power.”

    “On a purely cost basis, there is no question the hybrid wins out.”
    For now, diesels still are the absolute best fuel economy choice for long drives and highway commutes. Hybrids save fuel in stop-and-go driving using stop-start technology that shuts down the gasoline engine when it's not needed. Hybrids also use regenerative braking to recharge the batteries and computer technology to maximize the fuel economy and performance gains.

    Toyota has more of this coming in its next generation of hybrids, too.
    For instance, the revised edition of the RX 450h hybrid uses an updated version of the 3.5-litre V-6 engine. For 2010, it will run on the Atkinson combustion cycle, helping to improve fuel economy while upping horsepower by 27 over its predecessor.

    The Atkinson cycle closes the intake valves later than normal to improve fuel economy and emissions in hybrid power trains. The revised model's engine and electric motor combine to generate 295 hp.

    In addition, to improve fuel economy, the RX 450h engine has an exhaust-heat recovery system that allows the engine to stop and start more efficiently when the vehicle is halted. An exhaust-gas recirculator also reduces pumping losses.

    Officials from Ford of Europe agree that with the price of diesel fuel soaring, along with the cost of more advanced diesel emissions technology, diesel is reaching a point of diminishing returns. However, BMW and Mercedes-Benz officials say they can move to the next level of emissions technology with very little extra cost.

    Well, we're going to find out who is right. President-elect Obama indicated during the recent campaign that he will support a waiver sought by California to slap on more stringent emissions standards, beyond those required by the U.S. Environmental Protection Agency. If California gains its waiver, passenger cars sold in the state will be required to go much, much further to cut emissions.

    The 2010 RX and the next Prius will be able to meet those standards with the latest in hybrids. But diesels which are now for sale in California, Vermont and other states would need to add further emissions technology to be sold legally.

    Finally, there is a Canadian connection here. Indeed, as reported in the Globe and Mail this week, British Columbia is joining California in a court challenge after the U.S. Environmental Protection Agency refused to implement the state's new vehicle emission standards. B.C. has filed a legal brief in support of California in the U.S.

    B.C. and California, along with six other states and three provinces, are part of the Western Climate Initiative to lower emissions from power plants, manufacturers and vehicles.

    “We should expect new regulations out of California going forward,” says Beatty. “I personally think that diesel's day is maybe never going to arrive because of the changes in regulations.”

    Naturally, manufacturers with big investments and expertise in diesels do not agree. Game on.
    Fonte: globeandmail.com

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