Changing climate: Ersatz future weather data for lifelong system evaluation

Buildings and their renewable energy systems typically operate for a lifecycle of well over 20 years. Due to this the climate that a new building or renewable energy system will experience, will change over their effective functional lifetime.  It is therefore crucial that these buildings and systems are designed with due consideration of a changing climate (BRANZ, 2005).  This paper discusses how Ersatz Future Metrological Year (EFMY) climate files are created and used to more reliably predict future system responses in changed climates.   Using simulation software, comparison is made between the EFMY files representing a future climate and the current weather files to ascertain any costs and benefits that they present.