The roof of a house is a good one since it doesn’t use up any more land; in the northern hemisphere a south-facing roof is best.

Solar panels consist of two different materials stuck together. Traditionally it’s silicon doped with phosphor, stuck to silicon doped with boron. Silicon forms 4 bonds, and to fit in with this, one dopant has a spare electron, one dopant has an electron missing. At room temperatures, thermal energy is enough to liberate the spare electron from one dopant, and it moves around until it ‘slots in’ with the other dopant.

You’ve just moved electrons from one side to the other, creating a charge difference and therefore an electric field/voltage.

When light hits the panel, it can be absorbed by an electron which uses its energy to move up an energy band in the semiconductor where it can move, leaving a ‘hole’ behind. The negative electron and the positive hole then move in opposite directions under the influence of the electric field you produced earlier.

Moving charge is a current, or electricity. You can draw this off by attaching electrodes to each end.
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I’m doing a physics masters in solar power.

This flow is electricity.
References :

http://how-to-build-cheap-solar-energy.blogspot.com/
References :