So here is an idea I had to get cheapish solar power via a trickle charger. I bought a portable Jump starter from Maplin for £19.99 and a 12V 1.5W solar panel for only £9.99 to keep it topped up with power.
Total cost £29.98!
I removed the tyre air compressor from the back and replaced it with a perspex plate and removed the jump leads. The Starter has a 12volt 17Ah/20HR battery as can be seen above and it connects to a volt meter and spot lamp. It can be charged by mains or by the car lighter socket.
By using the built in lighter socket on the side, the starter can be trickle charged by the 1.5W solar panel. In practice it keeps the battery topped up nicely but will not actually charge the starter from flat – for this you would need a more powerful solar panel.
I used this setup to provide power via the lighter socket to my mobile phones or laptop (anything that has a car lighter adapter) for camping when the car isn’t an option. It became a bit redundant when we bought a caravan this year and a 110ah leisure battery!
However, I remembered I had this kit when I stared looking into mobile internet access and mobile WiFi routers.