Environmental Impact of Coffee Cultivation

Note

In this article/study, we calculate the carbon footprint of coffee using our coffee farm Santa Rita as an example, from cultivation to roasting. Santa Rita is located in the Dipilto region in northern Nicaragua and is a small farm of 4.16 hectares. The figures are based on the 2021/22 harvest and, with the relatively low yield, represent only a snapshot in time. At the time of data collection, the farm was undergoing major renovation in many areas, resulting in a low harvest volume and thus a high carbon footprint per kilogram. However, the study primarily provides a framework that can be used to calculate the carbon footprint of other coffee farms and along the coffee chain.

The study summarizes key aspects of our work in the research and sustainability work area of the Coffee Makers. This area is led by environmental engineer Tobias Milz.

Abstract

The CO₂ balance for the 2021/2022 harvest was determined using the Cool Farm Tool. This is a 4.16-hectare farm in Dipilto, Nicaragua, operated by the Coffee Makers in partnership with Bridazul. The calculation is based on a yield of 268.26 kilograms of export-quality green coffee. The coffee farm was taken over by Coffee Maker GmbH in 2017 and has been undergoing renovation since then. During the period under review, fewer than half of the plants were in production (3,665 in production; 5,363 not in production). Fertilizers and pesticides were applied across the entire farm, not just on productive areas. Therefore, we expect a reduced footprint per kilogram in the coming years. This will be achieved both through improvements in practice and through yield increases as more trees enter production.

The practice at Santa Rita is that apart from harvesting and the initial cleaning of coffee cherries, no further processing steps are carried out on the farm. The harvested cherries are transported to the partner farm "El Arbol", which is 7.4 kilometers away, for further processing. The next steps then take place at Bridazul's dry mill in Dipilto, which is a further 23.3 kilometers away. The green coffee is shipped together with other coffees from the Dipilto region and reaches our roastery in Basel, where it is roasted and packaged.

The export-ready green coffee has a carbon footprint of 1.57 kilograms of CO₂ equivalent per kilogram, which corresponds to 101.15 kilograms of CO₂ equivalent per hectare and a total of 430.79 kilograms of CO₂ equivalent for the entire harvest.

We deliberately decided not to include the existing trees and unused areas of the farm as a carbon sink in the calculation. We cannot guarantee that the trees will remain standing for the next 50 to 100 years in the event of forest fires or the sale of the farm. If we were to include these, approximately 1,000 kg of CO₂ could be credited to the farm.

Distribution of emissions from roasted coffee from Santa Rita

Overall, our calculation of transport and the carbon footprint of the Coffee Makers roastery in Basel for 2022 results in a CO₂ equivalent of 2.96 kilograms of CO₂ equivalent per kilogram of roasted coffee, assuming a roasting loss of 15%. The distribution of this footprint is as follows: The majority, namely almost 1.85 kilograms of CO₂ equivalent per kilogram, is attributable to the roasted coffee, which corresponds to approximately 62.5%. The transport share is 22.5%, which equals 0.66 kilograms of CO₂ equivalent per kilogram of roasted coffee. The roastery accounts for a further 0.45 kilograms of CO₂ equivalent per kilogram, which is about 15%. The share of coffee from our own farm processed in the roastery is approximately 2%

Introduction

The study is an environmental impact assessment of the Coffee Makers' Santa Rita farm. It was created using the Cool Farm Tool.

Farm

The farm is Santa Rita with the associated area Mil Varidades, which has been owned by Coffee Maker GmbH since 2017. The farm is located in northern Nicaragua, in the Nueva Segovia Department in the municipality of Dipilto. The farm comprises 4.16 hectares and at the time of data collection had 9,028 coffee plants, of which 3,665 were in production. The farm has been undergoing renovation since it was taken over by Coffee Maker GmbH. Many plants were removed and new varieties were planted. As a rule, plants bear their first cherries after three years. This explains why only some of the plants are bearing fruit.

The cultivation method is agroforestry with manual harvesting. So far, it has been necessary to use pesticides to protect against Broca infestation or Roya, and synthetic fertilizers and pesticides to promote plant growth. The goal is to gradually phase these out. They are to be replaced by "biologicals" and self-produced compost. In the next step, Bridazul and the Coffee Makers are working to produce high-quality compost centrally and efficiently from by-products of coffee production.

The farm is located 7.4 km from El Arbol, another farm operated by Bridazul. Bridazul are the Coffee Makers' partners who operate the farm on site. Apart from an initial selection of the cherries, all significant post-harvest processes do not take place on Finca Santa Rita, but on El Arbol.

For further fermentation and drying of the cherries, the coffee is taken to Bridazul's dry mill in Ocotal, which is 23.3 km away. This is also where the office and laboratory are located. Before the coffee is exported, it is hulled at Edman Café in the same locality and packed in 30 kg jute sacks with liners.

Scope of Analysis

Environmental impact assessments typically only consider work on the farm. Since the farm would not function without partners, work outside the farm must also be included. Therefore, various factors such as energy consumption in the office and during processing must be proportionally allocated to the farm's coffees.

The Cool Farm Tool does not account for waste or packaging materials. This means jute bags, liners, and other packaging used either for the coffee or its production are not considered.

The different resource situation in different countries is also not taken into account in the calculation. Therefore, the calculation of energy consumption is based solely on a global average with respect to electricity use.

Uncertainties in the Data

A major criticism of Environmental Impact Analysis (EIAs) is that uncertainties are often overlooked or given little attention in communication<1>. However, every environmental analysis must deal with uncertainties and assumptions. Therefore, it is very important to identify these. Below you will find the uncertainties evaluated and contextualized by category.

We have evaluated the uncertainties using the German school grading system. From 1 (very low uncertainty) to 6 (no certainty).

Data Collection

Most of the data was collected on site in April 2022. Using a questionnaire specifically developed for coffee farms and comprising over 200 questions, all ecological, economic, and social factors were collected. Further details for the calculation were provided by Bridazul. Bridazul bills the Coffee Makers for all work including materials used on Santa Rita. This allows for precise tracking of what, how much, and when was used.

Furthermore, the Coffee Makers are the only buyers of coffee from the farm, so it can be precisely determined which processing was applied to which coffee. For the calculation, however, an average must be assumed, which affects water and energy consumption.

Results

The calculation shows that the total footprint of the 21/22 harvest is 420.78 kg CO₂ equivalents. This corresponds to 101.15 kg CO2e per hectare and 1.57 kg CO2e per kilogram of green coffee.

Energy Use (Electricity)

At 33.2%, energy emissions for processing are the largest factor. This is due to the fact that these are heavily processed coffees.

The coffees undergo a controlled fermentation process at Bridazul, which also provides a cooling facility to ensure a controlled environment. This results in high energy expenditure, even though the process only runs for one month per year. Assuming electricity costs of $0.05 per pound of green coffee, this corresponds to a consumption of 126.56 kWh for our coffees.

Fertilizer

On many farms where plants are exposed to full sun, fertilizers account for a large portion of emissions (> 80%). This becomes evident when looking at the assumptions in the studies used, for example, by Ecoinvent. Ecoinvent is a widely used environmental database. However, Ecoinvent does not have a dataset for coffee from Nicaragua, but does have one for Honduras. Because of the farm's geographical proximity to Honduras, this dataset can be used. It assumes an application of 343-223-221 kg/ha for NPK fertilizers, resulting in emissions of 10.11 kg CO2e / kg green coffee.

At Santa Rita, there is an application of 6.56-5.80-26.67 NPK fertilizer. Organic fertilizers are included here, as well as fertilizers for plants that are still growing and not yet producing.

The high fertilizer application in the Honduras dataset achieves a yield of 1,340 kg / ha. By comparison, Santa Rita's yield is 101.15 kg/ha. Thus, the yield is higher by a factor of 13.25. However, the factor for nitrogen (N) fertilizer application is increased by a factor of 52.29, phosphorus by a factor of 38.45, while only potassium has a factor smaller than the yield factor (8.29). However, it is expected that the yield will increase in the coming years as more plants transition into the production phase. (As a rule, coffee plants begin bearing cherries after three to four years.)

Transport

Transport is a major factor at 14.8%. This is mainly because workers and all materials must be transported to the farm, as only two employees live on the farm. However, the transport does not include the transport of coffee to the port. We calculate this separately along with shipping and transport in the EU.

Roads in remote regions of Nicaragua cannot be compared to roads in Switzerland, and the additional effort caused by unevenness or lack of paving must be taken into account.

Discussion

Comparison of Emission Data for Green Coffees

Existing environmental data for coffee vary greatly or are not available. Data in environmental databases such as Ecoinvent aim to provide broad applicability. Therefore, the focus is on producing countries such as Brazil, Vietnam, Colombia, Indonesia, and Honduras, which account for 85% of global supply. The remaining 15% is distributed among another 55 producing countries and therefore receives less attention in large-scale studies.<2>

Ecoinvent therefore does not have data for Nicaragua. Since Honduras is a neighboring country to Nicaragua and uses similar agricultural practices and coffee cultivation in Honduras is similar to cultivation structures in Nicaragua, a comparison is appropriate. The Honduras dataset shows 10.11 kg CO2e / kg green coffee<3>. The dataset from Carbon Cloud, a freely accessible database focused on food, shows 4.0 kg CO2e/kg green coffee<4> for coffee from Nicaragua. A study by Caravela Coffee, which also takes carbon storage through the agroforestry system into account, lands at approximately -12.7 kg CO2e/kg green coffee<5>. The farm under review is thus in the middle range of these values. If land use change were taken into account at Santa Rita, approximately 4 kg CO2e/kg green coffee would have been stored at Santa Rita. This only takes into account areas that are no longer managed as forest. Additionally, new trees and shrubs such as bananas and Inga would be added.