lågenergibyggnader

Lågenergibyggnader, commonly translated as low-energy buildings, are structures designed to use only a small amount of energy for heating, cooling, hot water, and electricity relative to conventional buildings. The term is widely used in Nordic countries but is applied internationally with varying thresholds and definitions. In practice, lågenergibyggnader are defined by specific energy performance targets, often expressed as annual energy use per square meter (kWh/m²/year) or as primary energy consumption, and they are achieved through a combination of efficient envelope performance, efficient systems, and sometimes on-site renewable energy.

Key design principles include a highly insulated and airtight building envelope with minimized thermal bridges, high-performance windows, and ventilation systems with heat recovery. Balanced or demand-controlled ventilation helps maintain indoor air quality while limiting energy loss. Efficient space heating and cooling technologies, commonly heat pumps or district heating, are complemented by energy-efficient lighting and appliances. Energy modelling during the design process guides optimization, and some projects incorporate on-site solar photovoltaic or geothermal resources.

Standards and frameworks used to define or certify lågenergibyggnader include the Nearly Zero-Energy Building (NZEB) standard in the European Union and the Passive House (Passivhaus) standard, along with national regulations that set targets or certification paths. Many lågenergibyggnader meet targets stricter than typical new-build requirements.

Benefits of adopting low-energy buildings include reduced energy costs, lower greenhouse gas emissions, and improved indoor comfort and air quality. Challenges can include higher upfront construction costs, the need for skilled design and construction, and ensuring proper airtightness and ventilation during and after construction. The concept continues to influence building codes and retrofit programs aimed at decreasing energy demand in the built environment.