perusvoimaa

Perusvoima, or perusvoimaa, is a Finnish term used in electricity generation to describe the portion of generation capacity that provides the baseline, continuously available energy required to meet the minimum demand of a power grid. In English, this concept is known as base-load power. Perusvoima is typically associated with a high capacity factor, meaning it runs most of the time, and with low marginal costs, once capital costs are covered. It requires substantial, long-term investment and stable operation.

In practice, perusvoima is supplied by plants designed for continuous operation, such as nuclear facilities and large hydroelectric installations. These sources are able to run at a steady output for long periods, delivering a predictable stream of electricity regardless of weather and short-term fluctuations. Other generation sources, such as wind and solar, are intermittent and contribute more to balancing the system and meeting demand as it arises, rather than forming the base.

The role of perusvoima in energy planning is to provide a reliable backbone for the grid. It is complemented by flexible generation, storage, and demand-side measures to handle variations in demand and supply. As energy systems incorporate more variable renewables, the exact share and operation of perusvoima may evolve, with emphasis on reliability and overall system flexibility.

See also: base load, capacity factor, nuclear power, hydroelectricity.