In the field of photovoltaics, we currently design - inspired by our knowledge of optical interrelations – concentrator cells with a combination of hemispherical, as well as alternately concave and convex surfaces. Even in unfavorable incidence of light they are able to achieve a high energy yield. In the future it should be possible, not only to generate more electricity on rooftops, but also to increase the range of electric vehicles. Concentrator cells are removable and can be used and removed on any surface. For instance, traffic lights could be operated with our removable concentrator cells.