Installed capacity
Installed capacity refers to the maximum output that a system, typically related to energy generation or consumption, can produce under optimal conditions. This is commonly used in reference to renewable energy installations (such as solar panels or heat pumps), combined heat and power (CHP) systems, or battery storage capacity within a building:
- Solar Panels (Photovoltaics - PV): Installed capacity refers to the total peak output (in kilowatts, kW or megawatts, MW) of all solar panels on a building when operating under ideal sunlight conditions.
- Heat Pumps: The installed capacity of an air-source or ground-source heat pump indicates its maximum heating or cooling output in kilowatts (kW).
- Battery Storage: For buildings with energy storage, installed capacity refers to the maximum charge/discharge rate or total energy storage (typically in kilowatt-hours, kWh).
- Combined Heat and Power (CHP) Units: The installed capacity of a CHP system represents its maximum electrical and thermal power output, usually measured in kW or MW.
Energy Performance Certificates (EPCs) and Building Regulations may reference installed capacity when assessing energy efficiency. Feed-in Tariffs (FITs) and Smart Export Guarantee (SEG) schemes use installed capacity to determine eligibility and payments for energy generation. Larger installations may require approval based on their installed capacity and potential grid impact.
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