Packhouse Action Group Water & Electricity Benchmarking Project: an industry initiative to identify and help manage risks
By Carina Wessels & Dianca Yssel, Blue North Sustainability
South Africa faces significant challenges in managing its water resources due to being a water-scarce country, receiving 40% less rainfall than the annual global average. This has an impact on agricultural value chains, from the farm level to packhouse and cold storage facilities. In addition to water scarcity, the country is also facing an energy crisis, resulting in increased electricity costs, and the more stringent loadshedding measures that have been in place further intensify the energy-related pressures faced by fresh fruit suppliers. Moreover, global markets are increasingly demanding that fresh fruit suppliers showcase environmental sustainability in their production and processing operations, as part of the worldwide push to reduce carbon emissions.
To address these challenges, the Packhouse Action Group (PAG) Water Benchmarking Project was initiated in 2017 as an industry initiative to identify and manage water-related risks at the packhouse and cold storage levels of pome fruit value chains. In 2021, an electricity benchmarking component was added, and the project is now in its fifth year for water benchmarks and its second year for electricity benchmarks. Blue North Sustainability (www.bluenorth.co.za) manages the project and reports to the PAG Steering Committee.
The objectives of the project are to conduct a water and energy consumption benchmark study to highlight areas where packhouses can reduce usage. The project aims to replicate this objective annually, with an increase in packhouse participation and more detailed data collection around water and energy management and recycling practices. The project also aims to encourage industry knowledge sharing.
Throughout the project, water use data were collected for three packhouse areas: Packing Lines, Cold Storage, and Ablutions, Canteen & Offices. Electricity data were also collected for three packhouse areas: Packhouse operations, Controlled Atmosphere (CA) operations, and Regulated Atmosphere (RA) operations. Nine packhouses participated in the latest round of the project, and two more packhouses have expressed interest in participating in future data collection rounds.
Results from the 2021 calendar year of the project
The findings thus far have served as the foundation for ongoing improvement processes, as evidenced by the observed progress in water metering and data recording from the first year of packhouses participating in the project.
Only one packhouse could provide metered data for packing line water use, of which the benchmark was 607 litres/tonne pome fruit packed. The 2021 water use benchmarks for cold storage varied between 3 – 9 litres/Tonne.Day, while the benchmarks for the ablutions, canteen and offices ranged between 52 – 67 litres/person/day.
The overall water use index (Figure 1) for each packhouse incorporates water use for all sections of the packhouse, excluding water consumption allocated as “other”. Variation can be ascribed to different water management practices applied (e.g., flume drainage cycles, flume technology age, cold storage protocols, cold storage duration). The majority of packhouses consumed 1 – 2 m³ of water/tonne fruit packed.
Looking at the 2021 electricity use, for packing operations, results from four packhouses that passed the data quality sense check (metered results) varied between 21 – 33 kWh/tonne fruit packed. This aligns with Bouwer’s (2011) benchmark of 15 – 44 kWh/ton fruit (all commodities). Metered results for CA operations varied between 0.3 – 1.9 kWh/Tonne. Day, while Bouwer’s (2014) benchmark for apples was <1 kWh/Tonne.Day. Metered results for RA operations varied between 2.2 – 6.1 kWh/Tonne. Day, while Bouwer’s (2014) benchmark for apples was 8 kWh/Tonne.Day.
The overall energy use index (Figure 2) for each packhouse incorporates energy use for all sections of the packhouse, excluding non-packhouse energy consumption (e.g., housing). Variation can be ascribed to the unique combination of facilities at the packhouses (e.g., varying CA storage capacities and strategies) and different energy management practices applied. The majority of packhouses consumed 150 – 250 kWh electricity/tonne fruit packed.
Figure 3 displays the Rand/kWh costs for each electricity source supplying the packhouses. Renewable electricity (solar) was the cheapest, while generator electricity was the most expensive. Load shedding in South Africa has led to greater reliance on generators, but their diesel use adds significantly to electricity costs. As a solution, exploring renewable energy and battery options to offset load shedding can result in long-term cost savings, despite the initial high investment required, in addition to lowering a business’s carbon footprint.
In summary
The PAG Benchmarking Project continues to provide valuable insights into the water and electricity consumption of pome fruit packhouses. The project highlights the importance of water/electricity metering in specific areas and accurate record keeping on which management decisions depend. Improved metering and record keeping are thus encouraged as a first step for fruit packhouses in their efforts to improve water and energy use efficiency. It is positive to note that some of the participating packhouses are already on this journey.
The quantitative results provide a baseline for packhouses to improve their water and energy consumption in future. The project offers a guide for improvement targets, as well as year-on-year comparisons to build value and raise discussion points that participating packhouses can use to start internal discussions.
Since its inception in 2017, the project has shown signs of reduced water consumption in specific areas of the packhouses, particularly at the packing line. Energy benchmarks also suggest a decreasing trend in consumption. However, more precise energy data from additional packhouses is necessary to confirm these trends.
Packhouses have shown positive efforts toward rainwater harvesting, such as installing more tanks and using the water for certain aspects of their operations. This is however only done at a few packhouses. Some packhouses have reduced their environmental impact by filtering or treating wastewater. It is also worth noting that most participating packhouses have existing energy management practices in place, and some are looking to expand their solar energy capability.
The PAG Benchmarking Project has played a critical role in identifying and managing water and energy-related risks and supporting the pome fruit industry in showcasing environmental sustainability in production and processing operations. If you would like more information on the project, please contact Dianca Yssel at dianca@bluenorth.co.za.
References:
Bouwer, J.J., 2011. Using a benchmarking approach to improve energy efficiency in fruit packhouses and cold stores. Proceedings of the 8th Conference on the Industrial and Commercial Use of Energy (pp. 30-33). IEEE.
Bouwer, J.J., 2014. Energy well spent. Innovate. Available: https://postharvestinnovation.org.za/wp-content/uploads/2017/06/Energy-well-spent-PHI-Project-2014.pdf
Tonne.Days is not an intuitive unit of measure and is explained in more detail below. The cold storage benchmark cannot only be based on tonnes of fruit stored, as cold storage protocols vary widely from one operation to the next. Some packhouses store pome fruit for short periods (days or weeks), while others store fruit for long periods (several months to almost a year). Tonne.Days deals with this neatly as it calculates the amount of water used to store one tonne of pome fruit for one day. An example is: 200 Tonnes stored for 1 day = 200 Tonne.Days 200 Tonnes stored for 3 days = 600 Tonne.Days