Sustainability indices for countries provide a one-dimensional metric to valuate country-specific information on the three dimensions of sustainable development: economic, environmental, and social conditions. At the policy level, they suggest an unambiguous yardstick against which a country?s...

In the European Union (EU) and in Germany the transport sector is the only sector with increasing CO2 emissions (in the EU by about 32 % and in Germany by about 1 % since 1990). Especially in road freight and air transport a further strong increase is forecasted. In the transport sector this...

Plug-in hybrid electric vehicles (PHEV) combine electric propulsion with an internal combustion engine. Their potential to reduce transport related green-house gas emissions highly depends on their actual usage and electricity provision. Various studies underline their environmental and economic...