Peaking power plant

A peaking power plant (or peaker) is a power station that only runs during peak hours of demand of electricity. Because of that, the price of electricity it generates is generally higher than the electricity generated by base load power plant, which operates continuously throughout the year. Peak hours may include hot afternoons when air conditioners are working.
Examples of peaking power plants are a hydropower plant, pumped-storage hydro power plant, and gas-fired power plant. Nuclear and solar power are not used in this way.