According to the study “The current greenhouse gas emissions balance of electric vehicles in Germany”, the main reason for the high saving potential of electric cars is the progressing energy transition in Germany. The increasing share of renewable energy in the power mix will lead to continuously decreasing greenhouse gas emissions from electricity generation in Germany. “This also improves the carbon footprint of electric cars,” says Martin Wietschel, coordinator of the Business Unit Energy Economy at Fraunhofer ISI. “An electric car purchased today benefits from the declining greenhouse gas emissions from electricity generation over its entire useful life. In contrast, a car with a conventional internal combustion engine emits a similarly high amount of greenhouse gases even in its 13^th year of use as it did when purchased.”

It is true that the carbon footprint of conventional diesel and gasoline-fueled cars is also improving due to the admixture of biofuels, but only slightly. In addition, it is expected that the growing use of unconventional oil reserves, for example, through fracking, will worsen the greenhouse gas balance of internal combustion engines.

The study lists four major actions that could further improve the greenhouse gas balance of battery-powered electric cars:

1) Charging at home using self-produced solar power. Almost half the owners of electric cars in Germany already have their own photovoltaic system, often with their own energy storage system. Using self-generated solar power to charge an electric car improves its carbon footprint even more. A 30 percent share of self-produced photovoltaic power in the battery can lower the greenhouse gas emissions of an electric car by an additional. 8 to 11 percentage points.  

2) Using green electricity from additional renewable sources. The owners of electric cars are already more likely to draw their power from green electricity providers. If their electricity supply is exclusively renewable, the greenhouse gas emissions of their electric cars can be 65 to 75 percent lower than those of conventional cars.

3) Using renewable energies when producing batteries. Significantly more greenhouse gases are emitted when producing an electric car than when producing a conventional one at present due to the large amounts of energy required for battery production. These upstream emissions of electric cars can be reduced by 30 to 50 percent if renewable energies are used when producing the batteries.

4) Smart load management. This delays charging an electric car until electricity is particularly cheap – which usually coincides with a high share of renewable electricity generation. Simulations calculated in the study show that this can further reduce the carbon footprint of electric cars by 4 to 6 percentage points.  

The study discusses several options that can be realized quickly on how users and industry can further improve the carbon footprint of electric cars.

The Fraunhofer Institute for Systems and Innovation Research ISI analyzes the origins and impacts of innovations. We research the short- and long-term developments of innovation processes and the impacts of new technologies and services on society. On this basis, we are able to provide our clients from industry, politics and science with recommendations for action and perspectives for key decisions. Our expertise is founded on our scientific competence as well as an interdisciplinary and systemic research approach.