GM representatives can interact with fans through the Facebook page. One fan asked about what happens to "summer gas" that might sit in the gas tank all the way until winter. Phil (from GM) posted a response by Andrew Farah, the Volt's chief engineer, who said that:
In order to meet strict evaporative emissions requirements the Volt has a fully sealed fuel system. This will cause the fuel to age slower. The real issue is seasonal fuel blends that can affect starting and driveability as outdoor temperatures change. Rest assured, we'll have a solution by launch.And some people say Facebook is only used to goof off at work.