Housing Assessment Modelling for Somerset

Analysing potential energy efficiency gains for Somerset housing

Project duration: October 2012 to May 2013

CSE has developed a comprehensive housing stock assessment tool called our Housing Assessment Model (HAM). HAM is a software programme which incorporates an enhanced 2009 SAP calculator, so it can provide SAP ratings and modelled energy demand for space heating, water heating and lighting at an individual property level.

See the HAM project page here for more details.

Usefully for local authorities, HAM also allows detailed analysis of options for improving the energy efficiency standard of a given housing stock. It can analyse the potential effects of individual measures and packages of measures, taking account of external factors (e.g. fuel prices) and assess the options based on investment costs, modelled occupant costs, payback, positive net present value (NPV), target SAP improvements, fuel poverty impacts and/or the carbon impacts.

Somerset HAM...

CSE put HAM to work for the seven local authorities of the Greater Somerset region. We analysed the housing stock for Bath & North East Somerset Council, Mendip District Council, North Somerset Council, Sedgemoor District Council, South Somerset Council, Taunton Deane Borough Council and West Somerset District Council.

We used licensed Experian household profile data for the region and combined this with other address-level datasets (e.g. Warm Front data, insulation scheme data, Building Control Services data and any pilot scheme data that the local authorities could obtain) to create the best possible combined housing and energy dataset with property details for every domestic address in the Greater Somerset area.

For each of the seven local authorities, CSE then analysed the housing stock database using HAM to produce:

1. Data and results directly relevant for the completion of the Home Energy Conservation Act (HECA). The reporting covered the following areas:

  • Local energy efficiency ambitions and priorities (e.g. summarising targets and scenarios modelled by local authority area) 
  • Measures that take advantage of central Government initiatives, such as the Green Deal, ECO and RHI
  • Measures delivered by local schemes/partnerships (in particular referencing Warm Streets and ECO pilot data)
  • A timeframe for delivery and national and local partners (drawing on the measures and packages modelled, targets agreed by the group and scenarios developed and modelled illustrated with graphs, charts and maps)

2. An in-depth Housing Assessment study aimed at helping to determine the potential for Green Deal and ECO in each local authority area, and identifying geographical areas to target for energy efficiency improvements.

3. Output address-level datasets in Microsoft Access that local authorities now hold in-house – these can be developed and supplemented with additional household level data subsequently collected, providing a long-term resource and tool to underpin future housing and energy planning. The output database enables the local authorities to easily interrogate, expand and make use of their address-level housing output datasets.

How the analysis looked

i) ECO mapping

This map shows the official ECO CSCO areas and areas mostly likely to contain ECO HHCRO eligible households. Each local authority was provided with maps specific to their region, showing:

  • The official ECO CSCO areas
  • Areas most likely to contain ECO HHCRO eligible households
  • Areas most likely to benefit the most from the Green Deal (in terms of largest amount of funding obtainable)
  • Areas most likely to obtain ECO Carbon (for solid-walled properties)

ii) Green Deal modelling

This table is an example of our Green Deal modelling outputs. Each report contained a summary of the impacts of two Green Deal scenarios: one with a 15 year Green Deal loan term, the second with a 25 year term (the maximum currently available through the Green Deal). Each report provided information on how the improvement scenarios would reduce bills, energy consumption and carbon emissions, and increase the average SAP rating of the housing stock.

iii) 10-year emissions reduction projections

We modelled a deployment scenario to suggest what might be achievable as part of a 10-year housing improvement strategy. The results looked at both the entire housing stock and a subset of the housing stock that was identified as those households most likely to take up the Green Deal. These graphs show the potential carbon savings that might be achieved over the 10 year period.

iv) Address-level databases

Each local authority was provided with an address-level database like the one above, with reporting functions and the ability to look up individual property information. This image is a screen grab from the database showing the property-level data that can be looked up for each address. This database tab includes a list of recommended improvement measures and their impact on the SAP rating, CO2 emissions, energy consumption and energy costs for that property. Green Deal and/or ECO funding details are also provided.

We can analyse your area too

If you'd like our team to provide an analysis like this for your area, please contact Janine Michael for more information: janine.michael@cse.org.uk or 0117 934 1414.

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