tulotarpeet

Tulototarpeet refers to the heating demand or thermal load required to maintain a specified indoor temperature in a building over a given period. In energy engineering and building physics, it denotes the amount of heat energy that must be supplied by a heating system to keep the indoor environment within target temperature bounds, typically expressed as annual energy use (kWh/year) or peak heating power (kW). The value depends on climate, building envelope characteristics, ventilation, internal heat gains, and the chosen indoor setpoint.

Calculation methods range from simplified degree-day models to detailed dynamic simulations. Inputs include exterior climate data, thermal transmission losses (through walls, roofs, windows), ventilation heat losses, solar gains, and internal gains from occupants and equipment. Results can be reported as total annual heating energy, peak load, or heat loss coefficients (W/m2K). The distinction between heating demand and actual energy use is important, since behavior and system efficiency influence the latter.

Applications of tulotarpeet include informing the design and retrofitting of buildings, energy performance certificates, and planning for heating systems and district heating networks. It guides decisions on insulation, glazing, airtightness, and control strategies to reduce energy consumption while maintaining comfort. In Finland, tulotarpeet is a standard metric in building energy assessments and regulations aimed at improving energy efficiency in the built environment.