Prima Roastery Sustainability Report 2022 - Supporting Commentary
Materials and Waste Streams – Page 23
In calculating and presenting our internal Materials received, used & discarded, our external Materials Dispatched, Materials collected by our compost scheme and Materials avoided through reuse, it would have been ideal to get our data converted to a common unit, such as kilograms.
There are some conversion tables that can help achieve a general conversion from litres to kilograms of a specific type of waste. But we struggled to settle on an appropriate rate which didn’t risk misstating our true impact. So we have presented the figures on this page using which ever unit (litres or kilograms) we had the most accurate data for.
This has made the information on this page less informative and difficult to put into perspective. But it is as accurate as we could manage. In order to improve this in future reports we will need to gather better data throughout the reporting period.
Materials Received, Used & Discarded:
In calculating our waste to landfill, recycling and organics we were able to look at the number of red (refuse), yellow (recycling) and green (organic) bin collections from our site during the period to get an approximate volume. We assumed 100% full bins at every collection for the calculation which is a reasonable assumption.
To calculate amount of materials we dispatch as part of our business we used sales data and purchase data. For example, we can see how many cardboard boxes we purchased in the reporting period, then weigh one of those boxes and calculate the total weight by item. Then we assigned end-of-life waste streams to each item (boxes = recycling, packing tape = landfill, coffee bags = compostable, coffee = organic). It’s important to note that these are the categories we assigned and don’t represent where these items actually end up. No doubt a huge proportion of our compostable bags don’t get composted and rather end up in landfill. And the same is likely true for coffee and some recyclable products.
One final note, our organics figure here represents coffee dispatched. Since it isn’t a critical pain point for our sustainability journey, rather than calculating it accurately we threw out a ballpark round number to hold place on the page and give some scale to the other key items.
This compostable packaging collection scheme was launched in June 2021 so this data only covers about 5 months of the reporting period.
In calculating weight of waste collected by our compostable packaging collection scheme, again, we were able to look at the bin collection reports for the period. Unlike our other waste stream collections though, these bins get weighed at collection so our data here is accurate.
We could also have used a volume measure (litres) here as well. But if we assumed bins were 100% full at every collection for the calculation we think that would have been an unreasonable assumption. So we would have had to guess at a modifier (50%?, 80%?) and given the bins mostly aren’t on our site but rather out at partner cafes, we didn’t have a good gut feel. If we did assume 100% full bins the volume would have been 6120L.
We got these figures using sales and purchase data. The waste/recycling/composting avoided was calculated as:
Coffee Tins – 1x tin avoids 4x 1kg Compostable bags
Milk Bottles – 2x Glass Reusable bottles avoids 1x traditional 2L plastic milk bottle
Again Again Cups – 1x AA Cup avoids 1x Compostable cup and lid
BYO Customer Containers – 1kg of coffee sold in a reusable container avoids 1x 1kg compostable bag
For coffee sacks, there is no waste avoided. They primarily get reused in peoples gardens.