Board Thread:General Discussion/@comment-25146373-20140706155204/@comment-24860474-20140707061704

It depends. Basically though you're going to want to be able to conceal them when your power is full, and reveal them to the sun when you need to charge your storage up. So sticky pistons to move the cover back and forward is one idea.

If you have access to a crevasse which is lit during the day, you can conceal your solar arrays under stone blocks, which means it will be almost impossible to spot that something is out of place - whereas odd depressions in the surface ground (you need to hide the piston under a minimum of one block) are more likely to be noticed.

Backup power is something you might want to look into, for example you could fill fuel cans and use them in a small array of generators when you want to stay hidden.