Solar cells are a proven solution for being self-sufficient from the electricity grid. Especially if you plan to stay overnight for several days outside campsites, you quickly reach the limits of charging the on-board battery. Solar modules from Solara, for example, are characterised by their ease of installation: They can be glued or screwed on. With a stable surface and flat mounting, it can even be walked on the modules of the M-series (price: from 289 euros) and they are non-slip. A separate mounting system is not necessary.