Elektroenergiaa

Elektroenergiaa, or electrical energy, refers to energy carried by electric charges in a circuit. It is the energy transferred when an electric current moves through a conductor under a potential difference. Electrical energy is commonly measured in joules or kilowatt-hours (kWh); one kWh equals 3.6 million joules. In practical terms, electrical energy powers light, motors, electronics and many industrial processes.

Electrical energy is generated in power plants or by distributed generation using various energy sources. Traditional plants burn fossil fuels or use nuclear reactions to drive turbines connected to generators. Renewable sources such as hydro, wind, solar, and geothermal also produce electricity, often with different cost and intermittency characteristics. The electricity sector increasingly relies on a mix of sources to improve reliability and reduce emissions.

After generation, electricity is transmitted at high voltage to minimize losses, then distributed at lower voltages to homes and businesses. End users convert electrical energy into usable forms, including heat in heaters, light in lamps, motion in motors, and information in electronic devices. Efficiency and losses occur at every stage, from generation and transmission to conversion in appliances.

Environmental considerations link electricity to climate policy. The choice of generation mix determines emissions, air quality, and resource use. Grids and storage technologies, such as batteries and pumped storage, help balance supply and demand and accommodate intermittent sources like wind and solar.

Historically, electrical energy emerged from 19th-century discoveries about electricity and magnetism, leading to practical systems for generation, transmission and distribution that shape modern civilization.