LAS Motorhomes are often asked about solar panels, we have previously done a case study on them, and as stated before they are fairly expensive and not very efficient in this country. To get the best from them you need to have them at 45 degrees from the roof, not flat on the roof and ideally tracking the sun. This becomes a very expensive product that will only produce enough power in strong sunlight.
The solar panels that we used to use are silicon wafer based cells, but now these have changed as things have moved on.
The new solar panels are flexible (they are delivered rolled up) they are also self adhesive, so fitting is made easy, you can stand on them without causing any damage to them at all.
These new panels are CIGS solar cells (copper, indium, gallium diselenide) are 70% lighter and are far more efficient. They will produce power in cloudy conditions, as well as in diffused light.
Another advantage is that they produce 100 watts per M2, making it easier to fit into confined spaces.