Existing Reap Users

Methodology and Data Sources

REAP uses economic modelling to understand the environmental impacts of consumption. It uses a combination of top level data that describes how the economy in the UK works; the environmental accounts produced by the ONS (Office of National Statistics); and National Footprint Accounts and bottom up data that describes UK consumption of industry and households.

The main concept of the REAP methodology is that is measures the environmental impacts of consumption. Every time someone buys a good or service there is an environmental impact associated with that. It is relatively easy to calculate the impact of a good or service that has an obvious (direct) impact - such as driving a car or using energy to heat a home, but more difficult when the impact is further up the supply chain. Looking at what people consume and combining this with what is happening in the economy means that we can attribute these supply chain impacts to the final user.

Assessing the impacts of goods and services by looking along the supply chain could be done using life cycle analysis, by looking at all of the inputs necessary to create a good or service. However, it is difficult to define the boundaries of this as supply chains can be very complex. The REAP methodology uses the top level models of economic interactions to ensure that every stage of the supply chain (even from abroad) for every product group is included when you attribute impacts, but the disadvantage of this is that the information is only available at product group level. In summary, the REAP methodology takes complete account of all economic interactions, but can not distinguish between specific goods, it can not compare one loaf of bread with another, it can only tell you the impact of bread, cakes and biscuits at the product group level.

To distinguish between different consumers we incorporate bottom up consumer spend, travel and energy use data into the model. This tells us what and how much consumers buy. We can then attribute the economic impacts of different products according to spend. At the regional level in the UK we can use survey data, such as the Family Expenditure Survey and the National Travel Survey to tell us this information. At a local authority and postcode level these surveys do not exist so we need to estimate spending patterns based on models. We use Mosaic profiles to estimate this spend.

Click on this link to download a diagram of the REAP model

More details on the methodology for REAP can be downloaded here

The methodology is also described in the Local Authority report downloads

How is the Ecological Footprint Calculated?

In order to generate an ecological footprint estimate for all local authorities in the UK the national Ecological Footprints are disaggregated by economic sector, detailed final demand category, sub-national area or socio-economic group. This is done by combining existing National Footprint Accounts with input-output analysis. Calculations in the empirical part are carried out by using supply and use tables for the United Kingdom. Ecological Footprints are allocated to detailed household consumption activities following the COICOP classification system and to a detailed breakdown of capital investment.

Why is waste not an indicator in the REAP model?

The indicators in REAP are based on what is reported by industries at a national level. For example, industries must report on their carbon emissions for the National Environmental Accounts. Therefore we can trace these emissions through supply chains and they can be attributed to the consumer. Hence, carbon is an indicator. Waste treatment is an industrial sector in REAP, therefore not an indicator, but a sector that is part of the supply chain of the goods and services. The impact of waste treatment is embedded in the emissions impact of a good or service.

What is an Input Output Table?

Input-Output tables provide a complete picture of the flows of products and services in an economy for a given year, illustrating the relationship between producers and consumers and the interdependencies of industries. In its general form an IO table shows the purchases made by each sector of the economy in order to produce their own output, including purchases of imported commodities (inputs) as well as the consumption of products and services by other sectors and final consumers, such as private households (outputs). The basic assumption is that what is produced by one industry must be consumed, either by other industries or by individual consumers. IO tables are the central element of economic National Accounts which are produced by national statistical offices. IO tables are also used to generate annual accounts of the Gross Domestic Product (GDP).