Energy Losses from Building Envelopes by Heat Radiation and their Countermeasures

The energy consumption of buildings depends on the infrared (IR) properties of both the atmosphere and the building envelope. The energy balance for a building's skin [1, 2]: ε σ T0⁴ = k' (Ti-T0) + αk (Ta-T0) + εJ + αs Js states that in the steady state the power lost by IR radiation equals the incident power. The energy influx from the inside of the building k' (T.-T), atmospheric counterradiation εJ (long-wave), total absorbed solar radiation αS JS (short-wave) and convective heat transfer αk (Ta -To).