End-of-life (EoL) in LCA: Impacts of waste & benefits of recycling.
End-of-Life (Eol) is the last life cycle stage of a product. To model End-of-Life (EoL) in LCA you need to know what happens to your product after it’s discarded. Will it be recycled, incinerated, etc – and how do you model this in LCA?
Footprinting & LCA
Updated on: August 23rd, 2023
7 min reading time
The End-of-Life (EoL) is the 5th product life-cycle phase in LCA: it’s the “grave”. Frightful (at first sight) as its name implies, this phase causes emissions and frowning faces alike.
It has two main challenges:
1. How do you find out what happens to your product after it’s discarded?
2. How do you account for recycled materials’ environmental benefits?
Understanding the principles underlying EoL modeling will make this phase so much easier to tackle! Thus, here you’ll learn:
How EoL – generally – is modeled
How to find input data for EoL
How EoL recycling is modeled (with our special guest: the construction industry)
How to approach EoL
Your product enters EoL when it is either:
Processed as waste: generally incinerated or landfilled, sometimes composted or left standing.
Recycled or reused in another product.
Your task is to:
Map your product system: find out what scenario applies to which part of our product.
Model these processes in your LCA software: by linking them to environmental data.
Let’s look at these steps in more detail!
Collecting data for EoL
1. Map your product system at EoL
What happens to your product at the end of its life? Find out which parts, percentages, or amounts of material are processed in which way. You’re essentially doing data collection – read up on this here.
You know this with certainty when you yourself are responsible for EoL-processing. E.g. when you have a take-back system for your product, like Mud-jeans who recycle their jeans. Having raw primary data on your EoL processes is the most accurate – and will result in the most accurate LCA results for EoL.
Otherwise, you need to make assumptions. Base those on industry data or waste statistics*, such as (from most to least specific):
(National) Industry averages, e.g. the Environmental Database of the Dutch construction industry. Unfortunately, such clear data doesn’t exist in most industries.
Making an assumption that actually reflects your product can be difficult. But really: a best guess is already great here! And if you can’t find helpful data, our Ecochain specialists can (help you) do this research.
*Waste statistics tell you how much of a material gets recycled/burned/landfilled in this industry/country/etc.
2. Link your product system to environmental data
Find out which processes take place at EoL, and link them to environmental (also called LCI-) data in your LCA software. There is abundant secondary data on standard waste- and recycling processes in LCI Databases.
Great! You already learned how you deal with EoL in a nutshell!
But, EoL gets complicated in one other aspect: modeling recycling. Are you ready?
Modeling the environmental benefits of recycling
When you incinerate or recycle materials, they can become useful! Burning wastes releases usable energy and heat. And recycling materials produces “new” materials. Thus, we gain so-called “secondary products” in our EoL-phase. (Newly extracted resources are called ‘primary resources’.)
Secondary products have their own life cycle. Their impacts need to be carefully separated from your initial product’s impacts. Thus, often improving the LCA results of your initial product.
LCA methodology differs in recycling
Where we draw the line between the initial product and secondary product(s) depends on the LCA guideline we follow. The ISO guidelines give room for movement, allowing several system models.
System models are a deep rabbit hole of LCA methodology. It suffices to know that at Ecochain, we use the system model “Cut-off”. A variation of “cut-off” is also used in EN15804 for construction-related LCAs. Product environmental footprints (PEF method) require another system model (called “50:50”), which we won’t cover here.
The “Cut-off” model of EoL-recycling
The Cut-off model “cuts off” the secondary product’s impacts from the initial product at the point where the secondary product gains economic value.
The point of cut-off comes with the question: would someone pay for the material in this state? E.g. you can’t sell sorted plastic waste, but make recycled plastic granules and sell those.
All impacts before this “cut-off-point” (e.g. recycling processes, producing granules) count towards the initial product. Secondary products go into their second life-cycle “burden free”, without production- or extraction impacts. Thus, using recycled input materials leads to much lower impacts than using virgin materials.
Now let’s take the construction industry as an example.
EoL example: the EN15804
The EN15804* is the basis for construction-related LCAs. Its modules C and D deal with EoL.
Module C: deals with the impacts of demolition, waste processing, and recycling processes.
Module D: gives you credits and penalties for processes lying beyond your primary product’s life cycle. This makes EN15804 different from the standard “Cut-off” method, which doesn’t give credits and penalties.
* And ISO_21930_2017, the norm it’s derived from.
Credits in Module D
Recycling (or burning) materials in Module C gains you credits for the produced material (or energy) in Module D**! Credits amount to the environmental impacts of a “raw material equivalent” – the impacts that producing an equivalent amount of material (or energy) of the secondary product from virgin materials (called primary products) or fuel would have. These credits are “negative impacts”, deduced from your LCA.
** To claim credits for producing secondary materials or energy, you need to prove that your recycling scenario is likely to actually happen! The specifics for that are written in BMB 126.96.36.199 (BMB = Bepalingsmethode Milieuprestatie Bouwwerken).
Penalties in Module D
Instead of deducing impacts, Module D can also add impacts to your LCA, as a penalty for ”losing” recycled input materials.
For example, you use recycled plastic as input for your primary product. However, only 30% of that will be recycled at EoL. This means you lose 70% of the recycled plastic. Therefore, lost material’s “raw material equivalent” production impacts are added to your LCA. These penalties make sure that production impacts are not lost from accounting.
Hi, I'm Lena. Researcher & writer at Ecochain. During my studies in Global Sustainability Science, LCA really captured my interest. It continues to fascinate me in my current Master in Energy Science, where I also conduct LCAs myself. I love researching & writing (and learning more!) about these crucial topics now for Ecochain's Knowledge Blog.