The German state of Baden-Wuerttemberg (which includes Daimler headquarters Stuttgart) plans to conduct a feasibility study of carpool lanes (Umweltstreifen), which can also be used by vehicles with low emissions.
As reported by the Stuttgarter Zeitung (via Green Car Reports), the special lanes will be open to EVs, PHEVs, and other vehicles that meet the new Euro 6 emissions regulations, which includes many of the newest gas and diesel models (and will include all new passenger vehicles sold after September 2015).
The study, which is expected to last for six months, will examine the impact of the “environmental lanes” on air quality and traffic flow, and investigate ways to limit access to qualifying vehicles.
Source: Green Car Reports, Stuttgarter Zeitung, Auto Express