The aim of this project is to explore the viability of a Carbon Accumulator Tool that will measure the CO2e (carbon dioxide equivalent) that is saved and stored on farm. These businesses can then demonstrate the contribution they make to climate change mitigation and benchmark their own activities.

Four activities were chosen to represent the key areas in which Scottish Agriculture participates in:

  • Woodland
  • Soils
  • Livestock
  • Energy

These activity areas are in keeping with the Scottish Government’s climate change and agriculture aims and were judged as having the potential to be measured in a way that would provide consistently collated and compared data i.e. all come to specific CO2e tonnage figure.

“The Scottish Government is committed to a reduction of 80% in Greenhouse gas emissions by 2050. Farming has a big positive role to play, managing carbon sinks in the form of soil, crops and timber. Farming is very much a part of the climate change solution.

(Environment and Agriculture – Climate Change, Scottish Government 2017)

The key activity areas are also aligned with the main sources of emissions in farming which are identified as the following:

  1. Enteric fermentation: Ruminant livestock produce methane through their digestion.
  2. Soils: Nitrous oxide and carbon dioxide are released as a result of activities such as ploughing.
  3. Manure/slurry: Livestock waste also emits methane.
  4. Fertiliser: Nitrous oxide that is not taken up by plants can cause emissions.
  5. Fuel/Energy: Use of machinery, vehicles, and so on.

During the scoping of this project, it was agreed that pilot farms would be required to demonstrate the variety of farming activities in Scotland. This would allow knowledge and understanding to be gained and carbon calculations for each specific farming practice to be tested. A minimum of three farmers per activity was required to enable comparisons and verifications. It was also decided to ensure that one activity (soil) would be compared across all nine Pilot Farms. A further farm would crosscut all four activities (Pilot Farm 5).

Table of Activities per pilot farmer:

Pilot Farm Pilot Farmer Woodland Soils Energy Livestock
1 Duncan McEwan X X
2 Andrew Elliot X X
3 David Aglen X X X
4 Robin Young X X
5 Stephen Mackenzie X X X X
6 Neil McAlister Hall X X
7 Angus McFadyen X X
8 Kate Rowell X X
9 Laurel Foreman X

CALCULATIONS

The project gathered data to reflect farming activities from 1st January 2016 – 31st December 2016. With the exception of soil, this enabled comparisons across a 12 month period. Soil was judged to be a stable asset which did not vary significantly over that time.

WOODLAND

Woodland is an activity which already has an established measurement practice. Scottish Farm Carbon was chosen as the partner to assist in this activity as it has systems in place which conform to ISO 14064-02. This specifies a wide range of principles and requirements to deliver high quality data that is independently verifiable.

Every Kw (kilowatt) of energy produced through a renewable source provides a CO2e saving over conventional (traditional) energy generation. Commonly used methods of on farm generation include; biomass, hydro schemes and wind turbines.

To measure the amount of energy saved through renewable sources, quarterly and annual statements were collected. The total Kw's produced were applied as a saving against the farm. The 1Green Book supplementary guidance: ‘valuation of energy use and greenhouse gas emissions for appraisal’, was consulted to provide the emission factors for electricity in 2016 (0.324kwh).

Livestock is a challenging area to measure but an indicator was chosen to provide a gauge of efficiency. The indicator selected was the calving percentage of a beef herd.

To calculate the carbon impact two KPI’s were used. Firstly, an average 600kg cow was estimated as producing approximately 2.8132 tonnes of CO2e per annum (this was calculated using the AgRE Calc tool – a Scottish Rural University College online free resource). Secondly, the average calving percent of a Scottish herd was calculated as 381 percent using live ScotEID (https://www.scoteid.com/) data.

Feedback was then collated from participating farms on the number of breeding cows and heifers put to the bull in 2015. Actual calving numbers were gathered from ScotEID on the numbers born against individual CPH (Country Parish Holding) numbers. This allowed the number of calves above or below average for each pilot farm to be calculated and a ‘saved’ or ‘wasted’ tonnes of CO2e figure efficiency applied.

Soil is the only activity which was measured across all nine pilot farms.  It makes up the vast majority of the CO2e tonnes savings captured in the Accumulator for this project.

Soil samples were taken from a representative sample of fields on each pilot farm (guided by the pilot farmers) and delivered to SAC (Scottish Agricultural College) consulting for analysis and reporting. Each sample was tested for bulk density and organic matter. This allowed a calculation to identify the tonnes of carbon per hectare to be carried out: g C/kg soil x kg soil/ha = t C/ha

IACS (Integrated Administration Control System) maps for each farm were used to plot where the results should be applied. The area of each field was then used to calculate a total carbon value for each field and for the overall farm.














1 First published by the Department for Business, Energy & Industrial Strategy 15th October 2012.

2 This was based on 10 cows which aren't producing any offspring and had minimum base inputs of 1 tonne of purchased barley, 100kgs of minerals, straw for bedding and feed, as well as grass for hay plus 30O litres of red diesel and 500 units of electricity.

3 This figure was calculated by dividing the number of calves (under the age of 12 months) by the number of female cattle aged between 3-4 years old and any other animal which has had a calf.