Specialty green coffee traders, sourcing from 26 origins on behalf of over 1000 roasters.

Carbon Knowledge Transfer Project (KTP)

Author: Dr Mandi Caudill is leading the Knowledge Transfer Project (KTP) at Falcon to identify and implement methodologies for measuring and mitigating carbon emissions in the coffee supply chain.

• The Knowledge Transfer Partnership

• Emissions

• Fieldwork

Read Mandi’s Journals

• Coffee Supply Chain

• Emissions model

• The Results

• Causes of emissions in coffee production and consumption

• How can emissions be reduced in coffee farms?

• Next Steps

The Knowledge Transfer Partnership (KTP) aka The Coffee Carbon Project

In 2021, Falcon Coffees received a grant from the UK government to support a Knowledge Transfer Partnership, a joint venture between Falcon Coffees and the University of Brighton. The project aims to develop a methodology to measure greenhouse gas emissions throughout coffee supply chains. It will focus on coffee production and processing. Then, it will recommend approaches to mitigate emissions.

Emissions

What are they and why are they important?

Greenhouse gas (GHG) emissions trap heat in the atmosphere. They contribute to global warming and climate change. Some GHG examples are carbon dioxide (CO2), nitrous oxide (300 times more potent than CO2), and methane (23 times more potent than CO2).
 
Human activities, such as manufacturing, energy use, and inorganic fertilizers, have caused emissions to be released in the atmosphere to a harmful level. Governments are increasingly asking companies to report their emissions. Consumers are also more interested in knowing the emissions of the products they are buying.  People across all supply chains are investigating ways to reduce emissions.
 
Everyone in the supply chain must be aware of their emissions. They can then take positive action for the future.

Fieldwork

Coffee producers who work with Falcon Coffees Peru in Jaén, Peru were the first to be part of the project.

In October 2022, we visited farms and surveyed 25 producers to gather information. We wanted to learn about potential sources that produce emissions as well as sinks that reduce emissions. We added questions about emissions for the 2022 harvest into the 2023 inspection survey. 146 producers participated in the survey.

At the start of the 2021 project, we reviewed scientific literature for methods to measure emissions on coffee farms. We also assessed the carbon accounting models currently on the market. We designed a survey based on our findings. It will gather information on items that could produce or sequester emissions. In October 2022, we surveyed coffee producers and took ecological field measurements on a subset of the farms.

From the preliminary data collected, we created a draft model for calculating emissions. In May 2023, we conducted more fieldwork to enhance our emissions model’s accuracy. We also included questions about farm emissions and sequestration in Falcon Coffees Peru’s 2023 annual inspection survey. This way, we can gather more data from a wider range of producers. In mid-November 2023, after many improvements and iterations, we completed the emissions model.

Read Mandi’s Project Journals

Coffee Supply Chain

The coffee value chain begins in tropical countries. That’s where coffee is grown, harvested, and processed. It ends in import countries. There, green coffee is bought, roasted, and sold for consumption.

For the past 3 years, we have been tracking our emissions starting from the mill or port, depending on where we take ownership of the coffee per the buying contract. We track the emissions to the warehouse in the import country, where the coffee is stored until it is shipped to a roaster. The Carbon Project is designed to measure the emissions from the farm and post-harvest process.

Every origin produces and processes coffee slightly differently. In some places, like Rwanda, farmers bring coffee cherry to be processed at a centralized wet mill, a washing station. No processing happens on the farm. However, in Jaén, Peru, where our pilot study was conducted, there is no centralized wet mill, so producers process the cherry on their farms. The two main methods of processing are washed and natural.

Pruning residue management
The way crop residues are managed can greatly influence the levels of emissions.
If residue is wet and left in a pile untreated, it emits methane as it degrades which is 23 times more potent of a GHG than carbon.
If it is mulched and spread on the farm or composted and aerated (for the pulp), fewer emissions are generated.

 

Pruning: trees and coffee
Coffee plants also sequester carbon. However, carbon is released when the trees are pruned, trimmed, or cut.
So the amount sequestered has to be reduced by the amount that is pruned.
Fertiliser use
Nitrogen fertilizers are one of the highest sources of emissions on coffee farms due to the nitrous oxide created which is 300 times more potent of a GHG than carbon.
Interestingly, heavy use of organic fertilizers causes similar levels of GHG emissions as inorganic fertilizer for on farm use – because of the nitrous oxide created - whether organic or inorganic nitrogen sources.
Type of shade management
Coffee farms can be managed in various ways - from monocultures of coffee plants to coffee grown in the understory of forests and all the gradients in between.
Coffee monocultures are called "sun coffee" to distinguish from coffee grown interspersed with other types of trees and vegetation called “shade-grown coffee” or just “shade coffee” for short.
We have grouped these management systems into three broad categories using percent canopy cover as the defining metric.
Production of fertiliser
Did you know that for inorganic (aka synthetic) fertilizers, the production releases almost as much emissions as the use? Huge amounts of energy and heat are required to manufacture chemical nitrogen compounds.
Fuel use: equipment and vehicles
On most small-holder coffee farms, minimal energy is used. Fuel is needed for equipment such as weed whackers or chainsaws, but that’s really it. On larger farms, fuel is used to transport workers to different areas of the farm.
PATIO DRYING and RAISED BEDS
There are no emissions associated with natural processed coffee at this stage because the coffee is not depulped (no compost or waste) or washed after fermentation (no wastewater).

Emissions model

Through this project, we have developed a model in R that calculates farm-level emissions. We have also created a survey intentionally designed with questions that coffee producers can answer.

This was one of the major shortcomings of the farm-level carbon calculators currently on the market that we wanted to improve upon.

The input data required to run the model was unrealistic to ask of a coffee producer. Furthermore, the calculators were not specific to coffee farming. All emissions models have assumptions and uncertainties, none of them are perfect. But we were able to draw on our deep coffee knowledge, the University of Brighton’s expertise in emissions, as well as my own background as an agroecologist working in coffee for the last 14 years.

The Results

We found that most emissions on the farms in our pilot study were caused by fertilizer use (44% of average emissions per farm). Inorganic fertilizer production caused 12% of emissions.
 
Compost of pulp residue was the second highest contributor (37%). Most of the farms in Jaén used a mix of inorganic and organic fertilizers and processed both naturals and washed coffee on their farms.
 
Woody biomass sequesters carbon, thereby reducing the net emissions on the farms. The farms we surveyed in Jaén were in the lower range on the shade coffee spectrum. Most of them were in the sun or partial shade category, with around 10-20% canopy cover level.
 
Shade coffee usually has about 40% canopy cover. However, we estimated that, on average, the incremental biomass growth in the shade trees reduced emissions by 8%.
 
The diagram below shows the average carbon footprint contributions for the farms we surveyed in Jaén for the 2022 harvest. Emissions for coffee are usually measured in kg CO2e of emissions per green coffee per year. “CO2e” means carbon dioxide equivalent. It accounts for the various potencies of all the included greenhouse gases. For more info, see the first paragraph on emissions. So for every kg of green coffee produced in that year, x amount of kg of emissions will be released.

Causes of emissions in coffee production and consumption

On coffee farms, emissions are mainly caused by fertilizer use, which releases nitrous oxide. Fuel use for equipment and vehicles releases carbon dioxide.
 
However, shade trees sequester carbon. They take it out of the atmosphere, reducing total emissions.
 
During the washed process, emissions come from wastewater after the coffee is depulped, fermented, and washed. These emissions include methane and carbon dioxide. Also, decomposing cherry emits methane and carbon dioxide after the coffee is depulped.
 
In the dry mill, emissions are mainly caused by electricity use (carbon dioxide).
 
During transport, emissions come from combustion of fuel (carbon dioxide and methane).
 
For roasting and brewing coffee, emissions are caused by electricity use (carbon dioxide).

How can emissions be reduced in coffee farms?

Lowering inorganic fertilizer use will reduce emissions. Inorganic fertilizers generally have more nitrogen than organic. Furthermore, the production of inorganic fertilizers is usually high in emissions.
 
Trees sequester carbon, taking it out of the atmosphere. They thereby reduce net emissions. The more shade trees on the farm, the lower the net emissions.
 
Natural processed coffee has fewer emissions on the farm than washed coffee. This is because waste, such as coffee pulp residue and wastewater, is much lower for naturals.

Next steps

We will submit our research findings to a peer-reviewed scientific journal. We will add a link here once that is published.

Now that we have our model and methods for measuring farm-level emissions, we want to expand to other origins. Every origin produces and processes coffee a little differently. We will need to tweak our model accordingly. We’re interested to find out how other places compare to what we’ve found with our producers in Jaén.

We are developing a carbon calculator based on data from Jaén. We will add it to our website for our clients to explore. Stay tuned for more…

Pruning residue management

The way crop residues are managed can greatly influence the levels of emissions.

If residue is wet and left in a pile untreated, it emits methane as it degrades which is 23 times more potent of a GHG than carbon.

If it is mulched and spread on the farm or composted and aerated (for the pulp), fewer emissions are generated.

Pruning: trees and coffee

Coffee plants also sequester carbon. However, carbon is released when the trees are pruned, trimmed, or cut.

So the amount sequestered has to be reduced by the amount that is pruned.

Fertiliser use

Nitrogen fertilizers are one of the highest sources of emissions on coffee farms due to the nitrous oxide created which is 300 times more potent of a GHG than carbon.

Interestingly, heavy use of organic fertilizers causes similar levels of GHG emissions as inorganic fertilizer for on farm use – because of the nitrous oxide created - whether organic or inorganic nitrogen sources.

Type of shade management

Coffee farms can be managed in various ways - from monocultures of coffee plants to coffee grown in the understory of forests and all the gradients in between.

Coffee monocultures are called "sun coffee" to distinguish from coffee grown interspersed with other types of trees and vegetation called “shade-grown coffee” or just “shade coffee” for short.

We have grouped these management systems into three broad categories using percent canopy cover as the defining metric.

Production of fertiliser

Did you know that for inorganic (aka synthetic) fertilizers, the production releases almost as much emissions as the use? Huge amounts of energy and heat are required to manufacture chemical nitrogen compounds.

Fuel use: equipment and vehicles

On most small-holder coffee farms, minimal energy is used. Fuel is needed for equipment such as weed whackers or chainsaws, but that’s really it. On larger farms, fuel is used to transport workers to different areas of the farm.

PATIO DRYING and RAISED BEDS

There are no emissions associated with natural processed coffee at this stage because the coffee is not depulped (no compost or waste) or washed after fermentation (no wastewater).