Why we built on EPA WARM v16 instead of a proprietary waste model
A home-grown set of waste emission factors would have shipped faster. Here is why we chose a public, peer-reviewed model instead, and what that means for the numbers you report.
Edat Hub team··2 min read
When we started building the waste module in ECOT, the fastest route was obvious. Gather a handful of emission factors, simplify them into a table, and ship. Plenty of tools do exactly that. We decided not to, and the reason comes down to a single question: when someone asks where a number came from, can you point to something they can check?
The problem with black-box factors
A proprietary waste model is a black box to everyone outside the company that built it. The factors might be perfectly reasonable, but nobody else can verify them. That creates three practical problems for the people who rely on the output.
- Clients can't cite it. A sustainability report that says "calculated using Vendor X's internal factors" invites the obvious follow-up question, and there is no good answer.
- Auditors can't trace it. A verifier needs to follow a figure back to its source. If the source is confidential, the trail stops at the vendor's front door.
- Results drift silently. When a vendor quietly updates its factors, last year's numbers and this year's numbers stop being comparable, and nobody outside the company knows why.
What EPA WARM is
The Waste Reduction Model (WARM) is published by the US Environmental Protection Agency. It estimates the greenhouse gas emissions, energy use and economic effects of different ways of managing waste. Version 16 covers 61 material types grouped into 11 categories, from aluminium cans and corrugated cardboard to food waste and mixed electronics.
For each material, WARM models six management pathways: source reduction, recycling, composting, anaerobic digestion, combustion and landfilling. It takes a lifecycle view, so recycling a material is credited with the emissions avoided by not producing new material from scratch.
Crucially, the model and its documentation are public and peer-reviewed. Anyone can download it, read the methodology and check how a factor was derived.
What building on WARM changed in ECOT
Building against WARM took longer than a simplified table would have. We had to represent all 61 materials, all six pathways, and the way WARM separates greenhouse gas results from energy and economic results. In return, every waste figure ECOT produces can be traced to a methodology someone outside our company can independently check.
It also shaped how the module works. Because WARM is designed around comparing a baseline against alternatives, ECOT's waste module is built the same way: you describe how a material is handled today, model an alternative pathway, and see the difference in emissions, energy and jobs side by side.
The trade-off we accepted
WARM is built on US data and US waste management practices. For organisations operating elsewhere, that is a real limitation, and we would rather say so plainly than hide it behind a proprietary model with the same limits. A public model with known boundaries is easier to defend than a private one with unknown ones.
That is the principle behind the whole platform. If we can't show our work, we don't ship it.