Exemplary Energy Weather and Climate Data Sales portal link: Exemplary Energy Weather and Climate Data sales
Weather is what actually occurs. In data terms, weather exists historically as observation records and in the future as forecasts.
Climate is the weather that is expected to occur long term based on historical records and any identifiable trends in those records.
Precipitation is mostly rain (but includes hail, snow, fog and dew) and is the sum of all water landing on the ground. Precipitation data has been added to selected files wherever half-hourly data is available.
ACDB format: Australian Climate Data Bank format was jointly designed by CSIRO and BoM in the 1980s and is now only used in NatHERS software.
EPW format: EnergyPlus Weather format was designed by the US Department of Energy (DoE) in the 1970s and, as amended, is a de facto world standard.
RTY -> Real-Time Meteorological Year
These are the weather data for the 12 months leading up to the end of last month. They are available as a once-off purchase or as an annually renewable service at a discounted price. They are used for calibrated simulations of buildings and energy systems for optimisation at commissioning and/or for operational monitoring for early detection and correction of substandard performance.
RMY -> Reference Meteorological Year
These are the climate data selected to be indicative of the recent past and accordingly lack extreme weather values. Using a Cumulative Difference Function (CDF) each of the 12 months is selected for its normality and concatenated into a notional climate year with smoothing if needed around midnight at the end/start of the month to avoid disjunctures of, say, a clear frosty night ‘becoming’ at midnight a warm, rainy morning. The CDF has weightings for the weather elements. RMY-A (50% weighting for solar irradiation), RMY-B (33% weighting for solar irradiation), RMY-C (8.3% weighting for solar irradiation) are produced for targeted applications: A for (passive solar) housing and daylight-dominated commercial buildings and solar energy systems; B for small to medium non-residential buildings; and C for projects which are solar insensitive like deep plan buildings.
RMYs for the 34 years 1990-2023 are provided as an update of the de facto industry standard of 1990-2015 (see below). RMYs for the more relevant years for an inferred current climate – the 15 years 2009-2023 – are also available.
ISMY -> Industry Standard Meteorological Year
ISMYs have been developed as RMY-A files in the ACDB format for the years 1990-2015 originally for application in house energy rating software used in NatHERS and cited in the NCC. Ignoring the limited relevance of RMY-A to non-residential buildings, CSIRO has converted these files to EPW format but with gross errors (the solar data is mistimed by half an hour and the other weather elements are out by a whole hour) and these have become a de facto ‘industry standard’ despite the known misleading results that they give. Exemplary has corrected these errors to provide reliable simulation results with climate data equivalent to NatHERS.
EFMY -> Ersatz Future Meteorological Years
EFMYs have been generated for the two-decade era centred on 2050 based on 4 different world Greenhouse Gas emission scenarios. CSIRO’s Climate Science Centre produced a report including monthly Projected Change Values which Exemplary applied to the hourly data in the baseline RMYs. These EFMYs avoid the gross timing errors in CSIRO’s RMYs and in their projected future climate files based upon them (see ISMY above).
XMY -> eXtreme Meteorological Years
Using our published methodology, Exemplary developed these four XMYs to allow design and financial evaluation of flat-plate solar PV systems and farms including Building Integrated PV. They are P01, P10, P90 and P99 where P01 is the projected sunniest year in a century (1 per cent) and P99 is the cloudiest year in a century. P90 is the solar availability that developers are 90% sure will be exceeded in any given year (usually focused on the first year of a system’s operation). XMYs for Water Penetration and Condensation (XMYWPC) and for Heating Ventilation and Cooling (XMYHVAC) are still under development.