Bad news for green-car fans: SUVs are back, and sales are stronger than ever.

Good news: They're not the same old SUVs.

Don't resign yourself to a hermetically-sealed, solar-powered bunker to avoid the pollution from all those sport utilities just yet.

The new SUVs and crossovers are significantly different from the ones that first rose to prominence 25 years ago.

As Bloomberg reports, SUV sales are going gangbusters right now.

Jeep sold 41 percent more cars last month than it did in June. The Chevy Tahoe number increased by over a half. The diminutive Buick Encore soared 80 percent.

2015 Chevrolet Tahoe

2015 Chevrolet Tahoe

While parts of the Jeep range, and certainly the Tahoe, are designed along the lines of 'old-school' SUVs with large engines and bodies mounted on separate frames, all are significantly more economical than their forebears.

And the Encore is one of a growing range of vehicles in a class that hardly existed 15 years ago: the compact crossover.

MORE: Ten Compact Crossovers With Great Gas Mileage

Okay, Honda's CR-V, Toyota's RAV4, and the Subaru Forester have been around since the mid-1990s.

But the last few years have seen an explosion of smaller SUV-styled vehicles that get closer on fuel efficiency to regular sedans and hatchbacks than any previous SUV.

The best compact crossovers are rated at more than 30 mpg combined, and some offer highway mileage in the mid-30s. That's not so far behind the latest generation of regular compact vehicles.

That buyers can now have SUV style with regular-car economy is clearly proving popular: IHS Automotive figures show that SUVs and crossovers made up 36.5 percent of vehicle sales this year through May.

2014 Jeep Cherokee Limited 4x4, Catskill Mountains, NY, Jan 2014

2014 Jeep Cherokee Limited 4x4, Catskill Mountains, NY, Jan 2014

Regular sedans, which led SUVs and crossovers by a few percent a year previous, now sit 1.1 percent below utility vehicles in year-to-date sales.

Jeff Schuster, an analyst from LMC Automotive, describes America's love-affair with the SUV as "on-again, off-again"--but as their fuel efficiency continues to rise, it's likely it won't be "off again" for quite some time.

He notes that increased SUV sales in general mean consumers are expressing confidence in the economy--as they were before the global economic crisis in 2007, when the remaining buyers flocked to more economical and less pricey vehicles.

ALSO READ: 2015 Lexus NX 300h Hybrid: First Drive Of Luxury Compact Utility Vehicle

Ironically, for vehicles once criticized for their environmental impact, the climate itself might have led to the most recent spike. Last winter's extreme low temperatures and heavy snow may have spurred purchases of vehicles with all-wheel drive and raised ride heights.

The buyer profile for crossovers and SUVs is changing too.

Younger buyers, those starting families, are moving from existing vehicles into smaller crossovers. Those crossovers are also perfectly poised for older buyers whose kids may  have left the nest, since they no longer need quite as much capacity.

2014 Toyota RAV4

2014 Toyota RAV4

It's worth pointing out that buyers could see even greater fuel efficiency by trading to regular compacts, or perhaps swapping their larger SUV for one of the latest generation of hybrid midsize sedans.

But realistically, buyers want what they want--and will buy it if they can possibly afford it.

If U.S. car buyers want crossovers and SUVs, then the fact that they are more frugal than their forebears still means lower fuel use and emissions.

And for that, thank the imposition of new and tougher corporate average fuel economy rules by the EPA and NHTSA for the 2012 through 2025 model years.

You didn't really think those SUVs got more fuel-efficient on their own, did you?


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