Five MORE Big Myths About Green Cars And Gas Mileage, Debunked

Yep, Big Oil is definitely scheming and plotting to destroy the electric car. Everyone knows that. Right?

[sigh] Time for more mythbusting, it seems.

The surprising success of our first debunking of five green-car myths led us to look at five more relatively common ideas and explain ... well, as they say: NOT.

MORE: Five Big Myths About Green Cars And Gas Mileage, Debunked

Some are about saving money on gasoline, others are more general in nature. They come from our readers and from articles we've read that propound rather, errrr, creative ways of looking at green cars, vehicles in general, the auto industry in specific, and the world energy industry.

Here we go.

(1) Any green or high-MPG car will save you money.

This is often the case, but it's far from universally true. It's the flipside of the notion that high-efficiency cars cost so much more than comparable gasoline cars that you'll never make back the additional cost.

Both notions require you to combine the initial costs and difference in gas mileage--or cost-per-mile for plug-in electric cars--with your assumptions about how long you will own the car and what will happen to the price of gasoline.

If you compare a 2014 Toyota Corolla LE Eco, at 35 mpg combined, to a 2014 Toyota Prius at 50 mpg, the additional cost for the Prius (using the base price of each model) is $5,500.

If you own the car for five years and drive 10,000 miles a year on $3-per-gallon gasoline, the Corolla will cost you $1,287 more in gas. So it saves you money against a Prius that costs $5,500 more.

On the other hand, since the Prius is technically a mid-size car, compare it to a 28-mpg non-hybrid 2014 Toyota Camry, at a price difference of just $1,725.

If you drive 15,000 miles a year on $4-per-gallon gasoline, and keep the car six years, the Camry costs you an extra $5,656. The Prius is a clear winner there.

In other words: You have to do the math.

(2) Owning one vehicle is always cheaper than owning two.

Once more, it may be true, but it's not always the case--depending on your circumstances.

One brand-new but very inefficient car--an 18-mpg 2014 Chrysler 300 AWD with the 5.7-liter V-8 engine, for example--there are cases where a 50-mpg Prius Liftback and a 50-mpg Prius C subcompact could save you enough in gasoline to offset the second car payment.

If your household has to cover 25,000 miles a year--not unusual with long commutes--then using the pair of Priuses for five years will save you 889 gallons of gasoline a year. At $4 a gallon, that's $3,556 each year--or almost $300 a month.

Which could be enough to cover the $6,440 difference between the Chrysler ($36,840) and a Prius ($24,200) plus a Prius C ($19,080) over five years' worth of car payments, plus the insurance for that second car.

This is just one example; your own circumstances, mileage, and personal preferences will obviously play into the calculations.

But again, you have to do the math. (As Barbie notoriously said, "Math is hard!")

(3) Big Oil is working quietly and nefariously behind the scenes to kill plug-in electric cars and keep the world enslaved to petroleum transportation.

We tend not to believe in conspiracy theories here, but this crops up again and again and again: Despite the valiant efforts of electric-car advocates, Big Oil is working quietly behind the scenes to crush the very idea of plug-in electric cars and prevent them from coming to market altogether.

Sometimes the theory comes with the eager assistance of the world's car companies, who also want to keep their customers enslaved to gasoline.

Here's why it's not true.

Oil companies plan far, far into the future. And their analysts are paid enough to understand that carbon-emission limits in Europe, Asia, and elsewhere--and rising corporate average fuel economy (CAFE) rules in the U.S.--mean that new cars will get much, much more fuel-efficient.

That means that the current global fleet of 1 billion cars will consume less and less gasoline over time.

Moreover, that existing fleet of cars isn't likely suddenly to cover more miles, so any hope the oil companies have of demand increasing has to come from more cars.

And, indeed, China and other parts of the developing world--think India, Brazil, and Russia--are eagerly snapping up cars. So much so, in fact, that by some estimates, the global fleet could double to 2 billion vehicles over the next 20 years.

But if new vehicles roughly double in efficiency over that period--and new vehicles cover the same miles each year as current ones do today--you end up with flat consumption of gasoline and diesel even with twice as many vehicles.

Oil companies know this.

They also know that the pace of improvement in battery technology is slow--about 7 percent per year--and that an entirely new infrastructure of cell-fabrication plants that doesn't exist today must be built if plug-in electric car volume is going to increase over time.

In chats with various executives in the oil and gas industries, the oil men (there are very few women) pretty much discount any noticeable impact on their business from plug-in electric cars for at least a couple of decades.