The CaRB2 model is intended to run alongside and support the National Energy Efficiency Database currently being developed by the UK Department of Energy and Climate Change (DECC), with the emphasis placed on the non-domestic sector.
The model uses several sources of data, with the most significant being property taxation data collected by the Valuation Office Agency (VOA), for England and Wales. A second important data source is Display Energy Certificates (DECs) for public access properties in England and Wales. The VOA data cover most of the non-domestic stock; major exceptions are agricultural buildings, places of worship and Crown properties (such as prisons and most of the armed services).
The VOA records contain data on the principal activity of the premises and in 90% of cases there are also records for floor areas. These two data types provide the primary inputs for the energy model, which then draws upon analyses of empirical energy consumption data from a sample of non-domestic premises, categorised according to activity. Analyses of the DECS provide floor area statistics for many of the premises that have no floor area data in the VOA, whilst also providing additional energy consumption data. Based on the VOA data, a key improvement in this new model is the identification of areas of premises that are not within buildings, such as storage land and vehicle parking areas. This generates a more accurate description of the stock of buildings, rather than the stock of non-domestic properties.
A new classification of non-domestic activities is being developed, but it is also be possible to adjust the model for use on historical data from the VOA. The energy intensities to be applied to the VOA (and other) sources of floor areas come from energy surveys performed by Sheffield Hallam University (SHU) and these are aligned with the new and previous activity classifications. Additionally, overall energy consumption is disaggregated into fossil fuel and electricity use, plus the end uses of the energy such as heating, cooking, computers and so forth. Some adjustments are made to the SHU energy intensities to reflect changes in energy consuming equipment, such as the increased population of computers and the efficiency of lighting.
|Bottom-up energy demand non-domestic stock model
|To provide a description of the non-domestic building stock and its energy consumption subdivided by activities and energy end uses
|England and Wales
|A snapshot of 2012, with comparisons against 2010, 2005, 2000 and 1995
Documentation will be produced in due course.