How does Agrecalc work?

Transforming farm data into emissions estimates, carbon sequestration figures and KPIs

The Agrecalc calculator is the backbone of our carbon footprinting service. Our calculation software transforms farm level data into emissions estimates, carbon sequestration figures, and key performance indicators.

The calculator uses equations published by the Intergovernmental Panel on Climate Change and the UK Government to estimate greenhouse gas emissions from all major on-farm and upstream sources, returning these estimates in the form of simple tables and charts. Agrecalc is based on the life cycle assessment (LCA) framework for evaluating the environmental impacts of products and processes. We calculate all greenhouse gas emissions related to agricultural production, up to the point when final products leave the farm gate.

In general, the data used by the Agrecalc calculator can be divided into three categories:

1. Inputs include all information the user provides about their farm system

2. Coefficients include emission factors for the carbon calculations and default data which fills in missing user inputs

3. Outputs include estimates of all major greenhouse gas emissions (CO2, CH4, N2O) from the farm and its products

Input data combined with scientific parameters

At its core, the methodology we use to calculate emissions from each source is relatively simple. Our calculator contains numerous equations that use farm input data and scientific parameters to estimate emissions. We start by matching user input data to a set of coefficients, which are then used to calculate emission intensity across the farm. For most major emission sources, such as manure management, fertiliser application, and imported feed, we use variations of the equation presented in the graph [assigned to Marc for design] to estimate greenhouse gas emissions.

Elaborate modelling for enteric methane emissions

However, farms are complex biological systems; this simple linear model cannot be applied to emission sources with internal system dependencies. For example, we use more elaborate modelling for enteric methane emissions, which are influenced by various factors including feed composition, animal weights, herd size, activity levels, and calving percentage. The same is true of crop residue emissions and soil carbon sequestration; these emissions depend on various management characteristics including residue removal, crop type, and yield. [Marc to redesign the graph]

The best tool to handle mixed allocation

Once emissions are calculated for all sources on the farm, these carbon footprint results must be allocated across farm enterprises and products. For example, Agrecalc directly allocates emissions from the production of home-fed silage to livestock and allocates emissions from home-produced manures to the crops to which they are applied. This graphic illustration demonstrates how our calculation software allocates resources and models interactions between multiple farm enterprises.

Validated benchmarks for comparisons

Agrecalc is currently the only calculator on the market that internally allocates emissions across multiple enterprises. After allocation of emissions across enterprises, we use the LCA economic allocation method to allocate emissions across multiple products within each enterprise. For example, for a cattle enterprise producing both meat and milk, total enterprise emissions are allocated between these products based on their economic value. This allows the carbon footprint to be expressed per kilogram of meat or milk, so results can be directly compared across farms.

agrecalc circle that shows how we combine science, research, practice and ethos
graphic depicting the flow of data into and out of agrecalc and the benefits associated with doing a carbon audit
The flow of data into Agrecalc, outputs, actions and benefits