Next dimension of building energy modelling?

Next dimension of building energy modelling?
16th June 2017 Alison Parker

CEE’s Steve Evans and Dr Rob Liddiard on a new kind of 3D modelling that is giving a deeper understanding of energy use in buildings and premises.

Imagine having an explorable 3D map of all the shops and offices in a town or city. For researchers and policymakers trying to find ways to reduce energy demand for non-domestic buildings this kind of tool would be invaluable in assessing what works in real life situations to reduce energy demand.

Our team from the RCUK Centre for Energy Epidemiology (CEE) at UCL is developing just such a map. The 3DStock project has trialled its techniques on central London, Leicester, Swindon, Tamworth and Milton Keynes and the team is currently working to extend the model to large parts of England and Wales. In keeping with the CEE ethos, the project innovatively combines large datasets from different sources to come up with new levels of detail.

Data sources and method

3DStock project leader Professor Philip Steadman says, “The 3DStock model uses Ordnance Survey (OS) AddressBase as a spine to bring together data about property tax ratings from HM Revenue and Customs (HMRC) and OS Digital maps. These datasets are joined using an automated address-matching process. The OS maps show building footprints and the HRMC data gives floor-by-floor area use for non-domestic premises. The result is a ‘self-contained unit’ (SCU) ready for analysis.”

As premises can occupy multiple buildings, or a single building can have many premises and businesses, the SCU helps to make sense of these complex relationships. 3DStock also digs deeper into the HMRC data for finer-grained detail on the use of different parts of premises, such as factory space, offices, kitchens, storage etc.

In addition, laser measurements (LiDAR) made by Environment Agency aircraft give more detail on the heights of buildings and their external forms. The 3D models are created by stacking the premises’ floor areas onto the map footprints, floor-by-floor, and then adding shape information from the LiDAR data. From this we can get a fair idea of building volumes, not just floor areas.

The latest innovation is that 3DStock now includes domestic premises, so the stock model is starting to enable the study of how the domestic and non-domestic building stock live cheek-by-jowl in much of the urban landscape. This is a key new development from previous similar models.

As well as being used for modelling the simple annual energy use of the building stock, 3DStock is the source of geometrical data and space use inputs to the dynamic thermal simulation model SimStock, another CEE innovation.

Advising government

This highly detailed model can then be checked against government energy use figures to assess the relative energy efficiency of many types of premises. This allows comment to be made on what works and what doesn’t in terms of energy efficiency initiatives.

The project work has already been used by the Department of Energy and Climate Change (now Business, Energy and Industrial Strategy) in its efforts to assess the relative merits of introducing renewable technologies such as solar, heat pumps and district heating networks. The 3Dstock model has also supplied information to the Department for Communities and Local Government for use in developing planning policy.

Steve Evans and Rob Liddiard are Research Associates at the UCL Energy Institute. Professor Philip Steadman is a Principal Research Associate and Emeritus Professor or Urban Studies and Built Form studies at the UCL Energy Institute.

Read more about the 3DStock project