Energy signature

File:Energy signature method to determine balance point temperature.png

In mechanical engineering, energy signatures (also called change-point regression models) relate energy demand of buildings to climatic variables, typically ambient temperature.{{citation |author=Eggimann Sven, Fiorentini Massimo |date=2024 |doi=10.1016/j.enbuild.2024.114348 |periodical=Energy and Buildings |title=Transferring energy signatures across space and time to assess their viability for rapid urban energy demand estimation|volume=316 }} Also other climatic variables such as heating or cooling degree days are used.{{citation |author=Gorazd Krese, Matjaž Prek, Vincenc Butala|date=2012|doi=10.5545/sv-jme.2011.160 |periodical=Journal of Mechanical Engineering|title=Analysis of Building Electric Energy Consumption Data Using an Improved Cooling Degree Day Method|volume=58 |issue=2 |pages=107–114 }} In most cases, heating or cooling building energy demand is analysed through energy signatures, but also hot water or electricity demand is considered.

Energy signatures make a simplified assumption of a linear relationship between a building's energy demand and temperature.{{citation |author=Martin Eriksson, Jan Akander, Bahram Moshfeg |date=2010 |doi=10.1016/j.enbuild.2020.109756 |periodical=Energy and Buildings |title=Development and validation of energy signature method – Case study on a multi-family building in Sweden before and after deep renovation|volume=210 }} This assumption allows for balancing accuracy with computation time, as the estimation of energy demand through energy signatures is considerably faster than using building performance simulation software. A crucial advantage of applying energy signatures is that no detailed information on the geometrical, construction, and operational characteristics of buildings needs to be available.