Solar Energy
Solar energy is the radiant light and heat from the Sun that can be captured and converted into electricity or thermal power.
How Solar Energy Works
- The Sun emits electromagnetic radiation across a broad spectrum, most of which reaches Earth as visible light and infrared heat.
- Photovoltaic (PV) cells, usually made of silicon, convert photons into electric current through the photovoltaic effect: a photon knocks an electron loose, creating a flow of electricity.
- Solar‑thermal collectors absorb sunlight to heat a fluid, which can be used for domestic hot water, space heating, or to drive a turbine that generates electricity.
Why Solar Energy Matters
- It reduces dependence on fossil fuels and cuts greenhouse‑gas emissions, helping mitigate climate change.
- Solar installations can be distributed (rooftops) or centralized (solar farms), providing energy security and reducing transmission losses.
- Costs have fallen dramatically; the global average price of utility‑scale PV electricity is now below $0.04 kWh.
A Concrete Example
A typical 5 kW residential PV system in a sunny region receives about 5 kWh m⁻² day⁻¹ of solar irradiance. Over a year it produces roughly 7,000 kWh of electricity—enough to cover the average household’s annual electricity use in many countries.
Solar Energy in Israel
- Israel enjoys one of the world’s highest solar irradiance levels, averaging 5.5 kWh m⁻² day⁻¹.
- By the end of 2023 the country’s installed solar capacity exceeded 2.5 GW, enough to power more than 800,000 homes.
- The Ben‑Gurion National Solar Energy Center and large‑scale PV farms in the Negev illustrate how both solar‑thermal and photovoltaic technologies are being deployed.
- Israel’s national plan aims for 10 GW of solar capacity by 2030, leveraging its sunny climate to meet a growing share of electricity demand.
Future Outlook
Commercial PV panels now achieve efficiencies above 23 %, and advances in storage (lithium‑ion batteries, pumped hydro) are making solar power increasingly reliable. Continued cost reductions and supportive policies suggest solar energy will play an ever‑larger role in the global energy mix, including in sun‑rich regions like Israel.