The largest, affordable, gas-electric hybrid car on the U.S. market isn’t a Toyota or a Honda. It’s the new-for-2008, family-size Chevrolet Malibu Hybrid, which stretches 16 feet from bumper to bumper, has a roomy, midsize sedan trunk and carries more than 16 gallons of gasoline.

Best of all, the five-passenger Malibu Hybrid offers the top fuel economy of all Malibus — a federal government rating of 24 mpg in city driving and 32 mpg on the highway.

The hybrid car with a larger exterior is the 2008 Lexus LS 600h L, but at more than $104,000, the LS 600h L luxury sedan is hardly “mainstream.”

In contrast, Chevrolet’s hybrid version of Malibu has a starting manufacturer’s suggested retail price, including destination charge, of $24,290. Unfortunately, today’s MSRP, plus destination charge, for the Mali- bu Hybrid — already increased from the original $22,790 starting price — no longer makes the Malibu Hybrid the lowest-priced, gas-electric hybrid on the market as officials at Chevrolet’s parent company, General Motors Corp., had hoped.

Both the 2008 Toyota Prius, which starts at $23,135, and 2008 Honda Civic Hybrid, which starts at $23,235, have starting retail prices that are lower than that of the Malibu Hybrid.

Add on delays in getting appreciable numbers of Malibu Hybrids out to dealers — caused in part by leaking nickel-metal-hydride battery packs on earlier GM hybrid vehicles — and the fact the Malibu Hybrid doesn’t have all the hybrid features of Toyota and Honda vehicles, and you can see why fewer than 800 Malibu Hybrids have been sold so far.

The leaking battery pack was “supplier issue,” according to Chevrolet spokeswoman Nancy Libby, and has been corrected.

But because new battery packs had to be diverted for installation in 2007 Saturn Vue and Aura hybrids with the problem, Malibu Hybrid production for the 2008 model year did not crank up for the numbers planned.

Still, the test hybrid had the clean, pleasing looks of all 2008 Malibus. Styling inside and out is modern. On the outside, the only thing that noticeably distinguishes the hybrid model from nonhybrid Malibus is the hybrid badging.

Inside, the Malibu Hybrid doesn’t have the eye-catching energy display — complete with a diagram of a car — that the Prius typically has. The reason: The Malibu doesn’t have a full hybrid system, one that can propel a vehicle for a certain distance at times on electric power only.

Rather, it is a “mild” hybrid whose fuel savings come primarily from the ability of the four-cylinder engine to turn itself off automatically when the car is stopped at traffic lights and stop signs.

Thankfully, there’s an “auto stop” light that comes on in the instrument cluster at these times so the driver knows the car is still OK, and hasn’t stalled or quit working.

But with the engine off, the Malibu isn’t using gas, resulting in improved fuel mileage.

The 2.4-liter, double overhead cam, Ecotec four-cylinder starts up on its own the instant a driver begins to lift a foot from the brake pedal. But be aware that some drivers may need to change their driving styles. I tend to try to stop a vehicle smoothly, but my gentle brake pedal movement often didn’t initiate the engine shut-off in the test car. The Malibu Hybrid’s regenerative braking also kicked in and would alter my planned braking distance.

I discovered I could get the engine to shut off when I pushed sharply on the brake pedal, but then the Malibu Hybrid stopped more abruptly than I liked.

Don’t worry that, on hot summer days, passengers will swelter in a car whose engine turns off automatically. The Malibu Hybrid monitors air-conditioning needs and in the test car readily started up the engine, even at stoplights when cool air was needed.

In combined travel, I managed 25.7 mpg. Even the Malibu Hybrid’s government rating of 24/32 mpg is less than those of the Prius, Camry Hybrid and Civic Hybrid, which have full hybrid systems.

A final note: There is a $1,300 U.S. tax credit available on the Malibu Hybrid. It doesn’t come at the time of purchase and isn’t cash. But buyers can document their purchase to reduce their 2008 federal income taxes by $1,300. Taxpayers subject to alternative minimum tax may not qualify.

Chevrolet Malibu Hybrid

Price as tested: $24,290

Type: Front-engine, front-wheel-drive, five-passenger, midsize sedan

Engine: 2.4-liter, double overhead cam, Ecotec four-cylinder with nickel-metal-hydride battery pack

Mileage: 24 mpg (city), 32 mpg (highway)

Built in: Kansas City, Kan.