Solar in brief
Solar power turns sunlight into electricity. Most of it comes from photovoltaic (PV) panels, on rooftops and in large ground-mounted farms.
It is the fastest-growing source of electricity in the world, driven by a dramatic fall in panel prices over the past fifteen years.
How it works
- Light frees electrons. Photons striking a silicon cell knock electrons loose, creating a direct current (DC).
- Cells form panels. Cells are wired into panels and panels into strings to reach a useful voltage.
- Inverters convert the current. Inverters turn DC into the alternating current (AC) the grid uses.
- Power flows to use or to the grid. Rooftop systems supply the building first; solar farms export through a substation.
Main technologies
- Utility-scale PV: Ground-mounted farms, often with trackers.
- Rooftop PV: Homes, businesses and public buildings.
- Concentrated solar power: Mirrors focus heat to drive a turbine, often with thermal storage.
Strengths
- Cheapest electricity in many regions
- Modular, from one panel to gigawatts
- Pairs naturally with batteries
Challenges
- Generation only in daylight, peaking at midday
- Land use for large farms
- Supply-chain concentration
Every renewable explained: Wind · Solar · Hydro · Bioenergy · Geothermal · Marine. Renewables in every country.