Three of the most commonly used carbon calculators in the sector are Agrecalc, Cool Farm Tool and the Farm Carbon Calculator. NFU livestock board chairman Richard Findlay and the union’s vice-president Tom Bradshaw tested them on their farms.
Agrecalc looks daunting at first glance, but once you navigate around the website it becomes easier.
Urea is specified rather than all N fertiliser and there is no differentiation between straw chopping versus baling in the model.
It does not consider sequestration from hedgerows or soil.
Result: 225.45 tonnes of CO2 equivalent (tCO2e), with no sequestration and no machinery accounted for.
It allows a very comprehensive accounting of inputs into livestock systems and accounts for productivity by looking at fertility and mortality.
However, to calculate methane emissions it required you to work out your livestock numbers in the same way as the Farm Carbon Tool Kit.
It covers by-products, such as wool, and allows a yearly comparison so you can see the progress being made.
My top tip is if you are not 100 per cent sure about some of your data, you can hover over the input box and it will give you industry standards as a guide.
Results produced at the end give useful charts to show your situation and provide tips on how you can go about improving your footprint.
Agrecalc provides the most in-depth look at your business with the ability to record information tailored to your system, without asking impossible questions.
When sequestration of soil is included it could be a popular system for livestock farmers.
Cool Farm Tool is a commodity based carbon calculator.
The tool allows you to conduct a maximum of five assessments free of charge, making it difficult if you have more than five crops on-farm.
It accounts for the impact of land use change (from forest to arable or vice-versa) and of reduced tillage for crop assessments.
Cover crops are also considered in its calculations. Result: 249.56tCo2e; calculates on a crop by crop basis. No machinery is accounted for.
The simplest tool of the three and most of the information required you will already know or it is at least easily accessible.
A spreadsheet helps you collate your information.
Results are clearly displayed with graphs to show you the source of your emissions which helps you focus on where greenhouse gas reductions can be made.
The main issue with this calculator is it does not include carbon sequestration.
This is a really important factor for livestock farmers as by grazing our grassland we are protecting a very important carbon store and this has to be quantified in our calculations.
Productivity questions and gains are also limited for livestock, so it would be difficult to track progress year on year.
In addition, it only gives you the carbon footprint of each product and not the entire farm.
Farm Carbon Calculator provides live results as you input data, allowing it to be used as a decision-making tool.
The sequestration section includes hedgerows, soil bulk density and soil organic matter, although the figures for sequestration seem larger than is realistic.
The materials and infrastructure/inventory section is not particularly relevant to arable farms.
Result: 456.01tCO2e before sequestration, -1669.43tCO2e with sequestration; machinery accounted for, but entire machinery across contracted area, so would only be a percentage of machinery emissions.
Sequestration counts for an enormous reduction and we are unsure how accurate this large sequestration value is.
It has the most in-depth approach to carbon sequestration and provides a live updated chart of your emissions, so can you see it changing during the process.
You can easily change your data to see how it will impact your emissions.
It allows you to account for renewable energies which have been used and exported.
It also includes capital items on-farm. But it appears to lack productivity related questions.
For example, it does not take mortality and fertility into account.
Methane emitted is calculated over a year, so they ask you to ‘include the average number of all types of livestock on-farm at any one time; for example, for one batch of 200 lambs for six months a year, input 100 lambs for the year’, which could get confusing when working out finishing cattle.
NFU’s Net Zero: Farm Status Indicator has been designed to provide an introduction to carbon calculation.
It is not a comprehensive calculator, but aims to provide a quick guide to practical measures growers can put in place on-farm to reduce greenhouse gas emissions.
For more information visit: nfuonline.com
The process is relatively straightforward providing you have all the data to hand, so it is crucial all farm records are up-to-date and accurate in order for the calculators to be as effective as possible.
Data needed to enter into your carbon calculator:
With a target of net zero carbon emissions by 2040, there is still a long way to go.
Visit the Net Zero home page to cut through the jargon and view our brand new showcase of some of the measures already having positive results on farms up and down the country.
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