DENVER (AP) -- If a big yellow taxi took away Joni Mitchell's old man in her 1970 environmental anthem, a little green hybrid might bring him back.
Denver's Metro Taxi has 40 Prius hybrids in its 400-cab fleet. Discount Cab in Phoenix has 75 Priuses. Luxor Cabs in San Francisco also uses hybrids.
Chris Cotter, Metro Taxi's director of sustainable initiatives, said Metro replaces one or two conventional cabs with Priuses each month on average, although the recession could slow that down.
Harold Morgan of the Taxicab, Limousine & Paratransit Association said more companies would switch to hybrids if they were roomier.
"The Prius is awfully small when you look at other cabs that typically are Ford Crown Victoria or Mercury Grand Marquis models," he told The Denver Post in Monday's editions.
Cotter said Metro has reduced the company's carbon footprint by 65 percent and its power bill by 60 percent.
The company runs its furnace on used motor oil from its cabs and uses energy-efficient light bulbs
He said Metro has spent more than $1 million the past couple of years for its green makeover.
Morgan, of the taxicab association, said Metro is "one of the greenest cab companies."
Mitchell's song "Big Yellow Taxi" protested environmental damage wreaked by auto pollution, expanding cities and agricultural chemicals. It's been recorded by many other artists, including Counting Crows.