Two brand-new hybrid cars took center stage at the Los Angeles Auto Show, what has become the biggest event in the world for new model introductions.

Though gas prices have dropped to four-year lows amid an economy in recession, new models from Honda and Chevrolet offer some significant advances in technology and styling and could become the first real challengers to the Toyota Prius for king of the green car hill.

The Honda Insight, released in 1999 as a 2000 model, was the first mass-market hybrid on sale in the United States. It sold in small but steady numbers, but was much slower than other Honda small cars like the Civic and lacked a rear seat.

The new Insight, which will go on sale next April, is a five passenger sedan and features styling which matches that of other Honda cars but looks more like a Toyota Prius than anything else on the market. It will be powered by a small four cylinder engine and an electric motor with power stored in the same type of nickel hydride batteries used in hybrids on the market today. Honda promises a base price under $20,000 while the current Prius starts at more than $22,000.

Chevrolet is straying far from the mold by offering a hybrid car with brand-new technology that will allow it to go 45 miles or without ever dipping into the gas tank. The model, known as the Volt, uses a new type of lithium ion battery that is much more expensive to produce.

Chevrolet says the Volt will be released in 2010 as a 2011 model, though an exact date has not yet been set.

Because of the cost of the batteries, the Chevrolet Volt will be set at a higher price point than the Insight, parent company General Motors says. But as GM struggles to stay afloat, Chevrolet representatives at the auto show promised deep tax breaks for Volt buyers.

With more and more automakers pushing the envelope of alternative powertrain technology, the real winner will be car buyers as each company tries to push the high efficiency model to greater heights.