FREEWHEELING / Hybrids and diesels save money on fuel, but the math is tricky

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Gasoline terms are hovering around $4 per gallon for regular unleaded and the grounds is mounting that the drive populace is fighting back by drive less and drastically altering their new-vehicle purchases in favour of fuel-efficient models.

As a result, gross sales of hybrid-electric vehicles are booming. By now, most of us understand the message that loanblends - which compound a criterion engine with some type of electric-motor thrust - are markedly more than efficient than conventionally propelled vehicles, particularly in stop-and-go drive and heavy traffic.

The accepted male monarch of the hybrids, Toyota Prius, is a roomy enough compact auto that presents 48 statute miles per gallon in metropolis drive and 45 mpg on the highway, according to the Environmental Protection Agency. Now ready to dispute the growth loanblend picks is a revived fuel-efficiency option - the Diesel engine.

There are a few Diesels here and there, but we'll really get to see the new moving ridge of diesel-powered autos and motortrucks beginning later this summertime when Volkswagen conveys back its economical TDI (Turbo Direct Injection) Diesel in the compact Jetta lineup.

This is a water parting twelvemonth for diesel, because although the new coevals of Diesel engineering is vastly better than the fetid and noisy Diesels you may retrieve from the discotheque years, new engineering intends the diesels' emanations will be clean adequate to sell in all 50 states. In effect, Diesel engines will be as "clean" as the gasolene engines that currently predominate our auto and motortruck market.

The best portion is that Diesels encouragement combustible economic system between 25 and 30 percentage compared to a gasolene engine. The Environmental Protection Agency states with an automatic transmission, the diesel-powered 2009 Volkswagen Jetta, which travels on sale in August, will present 29 mpg in the metropolis and 40 mpg on the highway. And there is grounds to believe these evaluations are conservative.

That's not arsenic fuel-sipping as the loanblend Prius, but there's another factor that you must see if you're looking to salvage money by using less fuel: how much more than a loanblend or diesel-powered vehicle costs in comparing to a more-conventional choice. That finds how much your new fuel-saving auto really is saving you and how long it will take to reimburse your investing in that fancy fuel-efficient technology.

The Numbers crunchers at say that as the terms of gasolene acquires higher, the "payback" clip for crossed vehicles is decreasing. It do sense because the higher the terms of gas, the more than money you salvage if you're using less of the stuff. Also in your favour is that some makers are beginning to noticeably cut the terms tag on hybrids.

Edmunds estimations that if gas is $3.61 per gallon and you drive 15,000 statute miles a year, the loanblend with the shortest payback clip is the Toyota Camry Hybrid, which go backs the other $889 it bes compared to a conventional four-cylinder Camry in just 18 calendar months - and less clip if gasolene costs more than the $3.61 used in the Edmunds analysis.

The celebrated Prius can salvage $989 in gasolene cost annually, and Edmunds information shows it takes 3.5 old age to retrieve the other cost of the Prius' high-tech crossed componentry.

Motor Tendency magazine studied the respective diesel-powered vehicles currently on sale or coming soon. The magazine figured payback clip a small differently, choosing to calculate how many statute miles you'll have got to drive to interrupt even.

Measured by that formula, the best Diesel investing come ups from Mercedes-Benz, where its strong and soundless 3.0-liter V6 Diesel can be bought later this twelvemonth countrywide in the company's ML- and GL-Class SUVs and R-Class wagon. Motor Tendency figs you can retrieve the sensible $1,000-or-so cost of the Diesel engine in as few as 17,000 miles.

For Volkswagen's Jetta, the Diesel investing can be recovered in 31,000 miles, Motor Tendency estimates, because the terms have yet to be set. An issue that have made computation of Diesel payback more hard is the cost of Diesel combustible is rising disproportionately versus gasoline, hence erasing the "bargain" terms Diesel combustible offered until recently.

Purchasing a fuel-efficient vehicle shouldn't be approached strictly in footing of "payback," however. Hybrids are fantastic to drive in traffic, often operating soothingly and silently only on electricity. And because of the high torsion end product of diesels, they present strong public presentation when pulling away from a halt and when passing play at main road speeds. Diesels also are the ideal engines for towing.

Let's not price reduction that economy combustible have virtues that spell beyond keeping a few more than 10s and mid-twenties in your wallet. Using less combustible do us less reliant on on foreign oil, and combustion less combustible also intends you're reducing noxious emissions.

© Motor Matters, 2008