Mercedes-Benz is researching a new type of solar module that could be seamlessly applied to the bodywork of electric vehicles – similar to a wafer-thin layer of paste. At 5 micrometers, the paste is significantly thinner than a human hair, weighs just 50 grams per square meter (less than half an ounce per square foot) and is packed full of energy. The active photovoltaic surface can be applied to any substrate, Mercedes-Benz said, and the solar cells have an efficiency of 20%.