3 ms·

I have a small amount of roof space so want to buy efficient panels.

• dredmorbius 12y ago
  Focus on cost, not efficiency, really. There's plenty of space for solar energy all told, on a net-metering or grid basis. Unless you've got an absolutely compelling need to generate the maximum amount of energy from a minimum space and/or weight (say: you're building a satellite or space probe), just seek to keep $/kW as low as possible over the anticipated life of your panels.