But this is a pilot project because to achieve this low RvP level, the refiner must extract a class of chemicals from gasoline called pentanes. There is no market for pentanes at present in California. If refiners had to produce large volumes of this kind of gasoline it could cause supply problems. The ethanol industry has a solution. Give ethanol an emission offset credit for the air quality benefits it produces.
Ethanol dramatically reduces carbon monoxide, one of the ozone-forming chemicals.
And while ethanol does increase the overall volume of VOCs emitted, it changes the kinds of VOCs emitted. Ethanol tends to substitute less reactive VOCs for those that are more reactive, so it should receive a credit for these environmental benefits. Others think the credit could be worth about 0.5. If so, refiners could make 5.8 or even 6.0 RvP gasoline, dramatically reducing the impact on cost or supply. California can ban MTBE but cannot unilaterally award ethanol an emission credit.