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Calculating how circularity reduces emissions



Circular economies have become an integral tool in the fight against climate change. Constraints on landfill and incineration have right constrained the system, but until waste is reused, it remains waste.


Comparing circular and linear economies can be a headache for many people. Since nonlinear models don't compare easily, because you prevent the accumulation of emissions in the first place!


So how do you calculate the emissions footprints of each?

There is a difference between open and closed loop recycling. Here's a worked example on why circular economies are a great way to reduce the footprint of manufacturing and supply.


Worked example:


Imagine you have 1kg of plastic products you make into a widget. The circular footprint should be quantified by economic value of the product, not simply the kg of material. The useful utility of plastics are as products, not simply as flakes or pellets. It may be:


1. Initial emissions (all of generation 1 as virgin plastic): 10.18kgCOe/kg of plastic. Diverts 1.2kg from disposal component of emissions


2. Collect and Mech recycle (into gen 2): +5.5kg

3. Freight and Logistics: 0.23kg

4. Collect and Mech recycle (into gen 3): +5.5kg

5. Freight and Logistics: 0.23kg


Total emissions: 21.64kgCOe/kg of value


Compare this with the virgin take-make-waste "cycle":


1. Initial emissions 11.38kgCO2e/kg (including disposal)

2. Second gen virgin plastic 11.38kgCO2e/kg (including disposal)

3. Third gen virgin plastic 11.38kgCO2e/kg (including disposal)


Total emissions: 34.14kgCO2e/kg of value


Note, of value is as usable product. So circularity, doesn't have a zero footprint chip and extrude but still results in lower emissions.


Explanation

It is important to first recognise that utility/use cases are what pulls demand for products. Customers need a thing, so we make a thing.


Products aren't designed just for the purposes of making the thing. They're driven by demand.


It can be difficult to make sense of this. But take a plastic spoon you can eat yoghurt with.


In the linear case, if you use [1kg of] spoons, dump it and do the same 2 more times, the total emissions are 11.38kg CO2 each time.


So if you eat 3 yoghurts on 3 different days with 3 virgin plastic spoons, you accumulate 3x 11.38 = 34.14kgCO2 of emissions per kg of utility for all 3 generations (aka use cases). It's across all 3, just like circularity has 3 generations.


In all cases, you only have 1kg of spoons at any stage. You don't have 3kg of spoons.


  • In the linear economy, by the end you have 1kg of spoons and 2kg of waste, with those two kg also losing the embodied emissions associated with each of them.

  • While in circular cases, it's the same 1kg going through the system. There isn't the extra 2kg of waste/virgin plastic for this demand, nor locked in emissions that go with it, because it's the same 1kg that you started with and the embodied emissions from gen 1 (initial) are baked in.


So the comparison should be what are the emissions by kg of "use case" not simply per kg of plastic. A lot of Lifecycle Analyses get this very, very wrong!


The next stage is to remove the distance this stuff travels and optimise the product overall.


This is why Automedi concentrates on decentralised, local circularity. If waste doesn't move anywhere, you keep the strength of the jurisdictional laws to enforce, as well as reduce the real-world emissions from transport. Improving air pollution in the process.


What do you think? Are you ready to use real circular microeconomies in your business?

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