One of the joys of the huge, splashy, raucous SEMA show in Las Vegas is seeing what manufacturers toss up in the air to show off.

Kia brought several customized cars, one of which falls into the green category: a propane-fueled mild hybrid version of its new, and well-received, Forte compact sedan.

The Forte Hybrid is really just a teaser, though, to get buyers thinking about Kia and hybrid in the same breath. The company is expected to introduce its 2011 Kia Optima Hybrid at the 2010 Los Angeles Auto Show, which opens in two weeks.

Meanwhile, the Forte Hybrid, minus a few custom flourishes added for SEMA, had been unveiled in Korea in March 2009 at a presentation about Kia's plans for hybrid, electric, and hydrogen fuel-cell vehicles.

Kia Forte hybrid unveiled

Kia Forte hybrid unveiled

The Forte Hybrid almost surely won't be offered here, at least in its current form. No passenger cars are currently sold running on propane, although aftermarket conversions are available for commercial vehicles.

At its launch last year, Kia said it had no plans to bring the hybrid Forte to the U.S., indeed to any market that didn't have "an excellent LPG distribution infrastructure". That pretty much limits it to Korea and China.

The closest related vehicle, the 2010 Honda Civic GX that runs on natural gas, sells a mere 2,000 copies a year, many to corporate fleets and taxi services.

Kia's SEMA Forte Hybrid concept is fairly subtle, as these things go. It has low-rolling-resistance tires mounted on lightweight alloy wheels, mild aerodynamic enhancements, and a lower ride height.

Kia Forte Hybrid Concept

Kia Forte Hybrid Concept

Inside, the seat inserts are an abstract pattern of green--of course--and there's a 1,200-Watt stereo fitted, almost compulsory at a show like SEMA.

The LPG 1.6-liter engine and mild hybrid system used in the Kia Forte Hybrid show car are the same ones used in the Hyundai Elantra LPI Hybrid, which debuted last summer for sale in Korea only.

A 10-horsepower electric motor fits between the engine and transmission. It is used both to restart the engine when the car stops, and to provide additional drive torque along with that from the engine.

The Hyundai Elantra and Kia Forte share components under the skin, so adapting the mild hybrid from one to the other is simple.

[ via Motor Authority]