GREEN WARE; Auto companies push environmentally friendly vehicles at Los Angeles show.(News)

Many of the alternative-energy vehicles shown at the Los Angeles auto show won't be on sale for years to come. But contrary to the assertions of environmental activists who say automakers are dragging their feet and should build 40-mpg Hummers now regardless of cost, car companies are making huge strides in the quest for future propulsion. Here's some of what we saw at the show:

1. Fuel Cell Ford Explorer. This hydrogen fuel cell Ford Explorer prototype, built for the U.S. Department of Energy, uses a center-mounted hydrogen tank capable of delivering 350 miles on one fill, more than any other fuel cell vehicle today. The fuel cell Explorer also holds the world record at 1556 miles driven in a single day by a fuel cell vehicle.

While the center-mounted tank intrudes slightly on the center-tunnel floor space, the rest of the apparatus (batteries, fuel cell and computer controllers) is tucked away so that this Explorer retains seating and cargo dimensions of the production Explorer.

2. Saturn Aura Green Line. Saturn bolsters its fuel-frugal arsenal with the addition of the Aura Green Line. The same Ecotec 2.4-liter, 164-hp hybrid powertrain first found in the Vue Green Line SUV powers the Aura. The result is a claimed 25 percent fuel-economy improvement over a non-hybrid Aura. Expect to see the Aura Green ...