Renewable Energy - Energy

☀️ Solar Energy

Photovoltaic (PV) cells convert sunlight directly to electricity via the photoelectric effect. Solar thermal plants use mirrors to focus sunlight and generate steam. The Sun delivers ~173,000 TW to Earth - more than 10,000x global consumption.

💨 Wind Energy

Wind turbines convert kinetic energy of wind into electricity via rotating blades and a generator. Offshore wind is more powerful and consistent. Global wind capacity is doubling roughly every 4–5 years.

💧 Hydropower

Falling or flowing water drives turbines. Currently the largest source of renewable electricity worldwide (~16% of global electricity). Large dams have significant environmental and social impacts but provide excellent storage capacity.

🌋 Geothermal Energy

Heat from Earth's interior used for electricity generation and direct heating. Iceland gets ~90% of its heating from geothermal. Excellent baseload power potential but geographically limited to tectonically active regions.

🌊 Tidal & Wave Energy

Harnesses the predictable energy of ocean tides and wave motion. Highly predictable unlike solar/wind. Excellent potential in high-tidal-range locations like the Bay of Fundy (Canada) and the Severn Estuary (UK).

🌿 Biomass & Bioenergy

Energy from organic materials: wood, agricultural waste, purpose-grown crops, or biogas from decomposition. Can be carbon-neutral if managed sustainably. Used for electricity, heating, and biofuels for transport.

🔋 Energy Storage

The main challenge for renewables is intermittency (no sun at night, no wind in calm). Solutions: lithium-ion batteries (Tesla Megapacks), pumped hydro storage, green hydrogen electrolysis, compressed air, and grid-scale flow batteries.

📈 Growth & Trends

Solar PV costs have fallen 90% in 10 years. Renewables are now the cheapest source of new electricity in most of the world. In 2023, renewables generated 30% of global electricity. The IEA projects renewables will cover 42% by 2030.