When your raw material grows in forests, gets baled in cornfields, and shows up as piles taller than a house, inventory management stops being a spreadsheet exercise and starts being an engineering challenge.
At Charm, our business depends on turning irregular biomass residues into stable carbon stored underground. As we scale our carbon removal operations, quantifying those piles early, accurately, and repeatably isn't just helpful — it's foundational.
That's why we partnered with Rebulk to explore a better way to measure biomass inventory using photogrammetry and computer vision — designed for real yards, real terrain, and real-world variability.
The Problem with Piles
Our biomass doesn't arrive in neat containers with barcodes. It comes as:
- Log piles from forest thinning and wildfire resilience projects
- Corn stover stacked in agricultural fields
- Material stored on uneven industrial yards
Every pile is different. Geometry varies. Moisture varies. Packing density varies. Even the ground underneath varies.
Traditional inventory methods often rely on visual estimates, loader counts, or bulk volume approximations layered with assumptions about density and moisture. That can work at a small scale. But when you're building a carbon removal supply chain, uncertainty compounds quickly.
We needed a system that could:
- Accurately estimate pile volume, even on uneven ground
- Account for air gaps inside piles (packing factor)
- Operate in remote sites with limited to no connectivity
- Produce geotagged, repeatable records
- Scale across multiple sites
Turning Photos into Inventory
The approach combines two core ideas:
1. 3D Reconstruction of Pile Geometry
Using drone or mobile imagery, overlapping photos are processed into a dense 3D model of the pile and surrounding yard.
Crucially, the system models the actual ground surface beneath the pile instead of assuming it's flat. Biomass yards are rarely perfectly level, and small baseline errors can meaningfully distort volume estimates at scale. Modeling the true terrain profile improves consistency and reduces bias.
2. Packing Factor Estimation
Bulk volume alone doesn't tell the whole story. Biomass piles contain air gaps between logs, branches, or stalks.
Side-view imagery is analyzed using computer vision to estimate the void fraction within the pile. That produces a packing factor — a measure of how much of the pile's bulk volume is solid biomass versus empty space.
Bulk Volume × Packing Factor = Estimated Usable Material Volume
This allows piles with very different internal structures to be measured in a comparable way.
From Snapshot to System
What excites us most isn't just that this works — it's that it works in the field.
The workflow is designed to be operator-friendly and usable in remote environments. Scans can be captured using standard mobile devices and synced later, which is critical for sites without reliable connectivity.
Beyond individual scans, the larger opportunity is building a time-series inventory system:
- Tracking how piles grow and deplete
- Improving forecasting and logistics planning
- Establishing a trusted internal source of truth
- Creating structured, traceable upstream data
Over time, this kind of visibility can inform decisions about yard layout, material movement, and operational efficiency — all without adding heavy process overhead to field teams. With geotagged inventories we can estimate transportation requirements of different feedstocks to our facility, and pre-emptively estimate associated embodied emissions impacts for our remote inventory.
Why This Matters for Carbon Removal
Carbon removal doesn't start at the wellhead. It starts with feedstock.
If you can't confidently measure your biomass inventory, you can't reliably:
- Plan pyrolyzer utilization
- Coordinate logistics
- Forecast material availability
- Reduce reconciliation friction downstream
Accurate measurement turns irregular piles into actionable data. Actionable data supports better operations. Better operations support scale.
And scale is the whole point.
At Charm, we spend plenty of time thinking about reactors, chemistry, and underground injection. But none of that happens without feedstock — and feedstock starts as a pile somewhere.
There's real climate leverage hiding in those piles.
We're excited about what smarter measurement unlocks: a more transparent, data-rich biomass supply chain that helps us move faster, plan better, and push carbon removal toward climate-relevant scale.
Because if you can measure your piles, you can scale your impact.
Run your bulk terminal on one platform
Whether you need to measure inventory, track railcars, process paperwork, or report to customers — Rebulk gives your team a single connected operating record.