General Motors will offer its bi-fuel Chevrolet Silverado and GMC Sierra pickup trucks starting at $9,500 and dedicated compressed natural gas vans starting at $10,825, the company has announced.

The 2015 Silverado and Sierra 2500HD and 3500HD in a bi-fuel configuration starts at $9,500. GM will offer the 2015 Chevrolet Express and GMC Savana full-size vans with a short wheelbase starting at $10,825 for the three-tank system and $12,090 for the four-tank system.

CNG versions of the Silverado and Sierra 2500HD in double cab or crew cab are available now, while the 2500HD regular cab and 2500HD pickups go on sale in July. The vans are available now.

GM offers a five-year, 100,000-mile warranty on its CNG vehicles, including the upcoming bi-fuel Chevrolet Impala sedan.

"Based on current average fuel prices, CNG is more than a dollar cheaper than an equivalent gallon of gasoline, giving drivers and businesses an incentive to use CNG to power their vehicles," said Ed Peper, vice president of General Motors Fleet and Commercial. "Given the consistent cost savings and expanding infrastructure, both commercial and individual interest in CNG vehicles continues to grow."