Kiwi Parallax
Invest-NL counted seven Dutch recycler bankruptcies in 2024. The team is modelling why plants close even as Europe’s rules ask for more recycled plastic.
How do material quality, resin prices, electricity costs and buyer commitments combine to decide whether a Dutch recycling plant survives?
Whether rules that require recycled plastic actually rebuild Dutch recycling, or get met with imported material instead.
Household plastic film · mechanical recycling · the Netherlands · 2022 to 2025
The structure shows where plastic and money can go. The feedback shows what those flows do to each other over time.
How the system is built
Two diagrams from model-based systems engineering. The first names every part of the system and what it carries. The second shows what flows between the parts.
What it’s made of
Block definition diagramEvery part of the Dutch household-film system the team chose to model, and what each part carries: capacity, prices, yields, contracts.
The team’s block definition diagram names every part of the Dutch household-film recycling system: households, municipal collection, sorting plants, recyclers, buyers of recycled plastic, and the producer-funded scheme that pays for collection. It records what each part carries, such as capacity, prices, yields and contracts, and marks the outcomes the model has to explain.
How it moves
How plastic travels from Dutch homes through collection and sorting to recyclers and buyers, and where it leaks out. Collected is not the same as recycled.
This view traces plastic film from Dutch homes through collection and sorting to recyclers and buyers, and shows where material leaks out of the chain. It separates what is collected from what is actually recycled.
How the system behaves
One map and five loops from system dynamics. They trace how a change in one place comes back around, either building on itself or pulling itself back.
Where it pushes back
Causal loop diagram · the whole mapAll five of the team’s loops on one map, and the three places where they meet.
The team’s loop map joins five feedback loops: financial viability, feedstock quality and recycling performance, domestic capacity and buyer confidence, correcting contamination, and closing the gap between recycled-content targets and actual use. It shows where they meet: operating cash, reliable domestic supply and feedstock contamination.
R1 · Financial viability (reinforcing, 5 variables)
When more buyers commit to Dutch recycled plastic, plants run fuller. Fuller plants spread their fixed costs over more output, which strengthens their finances. Stronger finances pay for maintenance, reliability and quality, and a more reliable supply draws in more buyers.
The same loop runs in reverse. Falling demand cuts throughput, weakens finances and squeezes reinvestment, and a less reliable plant loses more buyers.
- When buyer demand for domestic PCR rises, domestic PCR throughput rises.
- When domestic PCR throughput rises, operating surplus and cash rises.
- When operating surplus and cash rises, reinvestment in operations rises.
- When reinvestment in operations rises, reliable domestic PCR supply rises, after a delay.
- When reliable domestic PCR supply rises, buyer demand for domestic PCR rises.
Why it is reinforcing: None of the 5 links are negative. An even number of negative links makes a loop reinforcing: a change keeps feeding itself, in either direction.
What the team flags: The team's caution: throughput can only rise if there is enough capacity and feedstock to process.
R2 · Feedstock quality and recycling performance (reinforcing, 4 variables)
Investment in collection quality, sorting and contamination control can lower contamination. Cleaner feedstock raises saleable yield, which improves profitability, and better finances pay for further improvement.
In the other direction, weakening finances lead plants or their partners to underinvest in quality, and yield gets worse.
- When saleable recycling yield rises, operating surplus and cash rises.
- When operating surplus and cash rises, investment in quality control rises, after a delay.
- When investment in quality control rises, feedstock contamination rate falls.
- When feedstock contamination rate rises, saleable recycling yield falls.
Why it is reinforcing: Two of the 4 links are negative. An even number of negative links makes a loop reinforcing: a change keeps feeding itself, in either direction.
What the team flags: The team's caution: cleaner feedstock is not automatically more profitable, because getting it costs money too. Treat this as a possible mechanism that needs evidence. It links directly to the team's research on separation at home versus recovery from mixed waste.
R3 · Domestic capacity and buyer confidence (reinforcing, 4 variables)
Stable revenue lets a recycler finance and keep its capacity. Capacity that stays open makes Dutch supply reliable, reliable supply wins buyer commitments, and commitments stabilise revenue.
When demand is weak and finances deteriorate, plants go idle or close. Dutch supply becomes less reliable and can push buyers toward imports or virgin resin.
- When revenue stability rises, ability to finance capacity rises.
- When ability to finance capacity rises, reliable domestic PCR supply rises, after a delay.
- When reliable domestic PCR supply rises, buyer purchasing commitments rises.
- When buyer purchasing commitments rises, revenue stability rises.
Why it is reinforcing: None of the 4 links are negative. An even number of negative links makes a loop reinforcing: a change keeps feeding itself, in either direction.
What the team flags: Capacity does not shrink smoothly: a plant runs until it crosses a financial threshold and then closes, as “Optimized, and Still Failing” describes. The team marks that link with both a delay and a closure threshold, and does not assume every loss of capacity lowers buyer confidence. That is a relationship to test.
B1 · Correcting contamination through feedback (balancing, 3 variables)
As contamination rises, collection coordinators and sorting operators could step up their efforts. Better sorting guidance, service design or technical improvements could then bring contamination back down.
- When feedstock contamination rate rises, pressure to improve collection and sorting rises.
- When pressure to improve collection and sorting rises, quality improvement effort rises.
- When quality improvement effort rises, feedstock contamination rate falls, after a delay.
Why it is balancing: One of the 3 links is negative. An odd number of negative links makes a loop balancing: it pushes a change back toward where it started.
What the team flags: This feedback is not guaranteed to exist. The team asks who detects a change in contamination, who is responsible for acting, who pays, and how quickly the fix takes effect. If no one can or will respond, the loop may be weak or missing entirely, as the “Many Minds, and Four Rules” reading describes.
B2 · Closing the gap between PCR targets and actual use (balancing, 3 variables)
This is a policy pathway. A buyer who falls short of a recycled-content requirement may step up its purchasing, which raises the verified recycled plastic it actually uses and closes the gap.
- When PCR use shortfall rises, buyer effort to procure compliant PCR rises.
- When buyer effort to procure compliant PCR rises, verified PCR actually used rises, after a delay.
- When verified PCR actually used rises, PCR use shortfall falls.
Why it is balancing: One of the 3 links is negative. An odd number of negative links makes a loop balancing: it pushes a change back toward where it started.
What the team flags: The target is set from outside and does not rise with anything else in the loop, so it is drawn as a dashed box. Crucially, this loop can raise verified recycled-plastic use without adding any Dutch recycling capacity, because buyers can meet the rule with imported material. The team calls this one of the most important distinctions its diagram could reveal.
System model by Kiwi Parallax, Fall 2026 cohort · loops drawn from the team’s loop plan ·
Hannah Sun
Marion Munini Muli
Zeynep Kardelen Ozturk