Wash water is the least green part of a recycling business

The uncomfortable part

Every environmental claim this company makes rests on reuse being dramatically better than manufacture. It is — about eight times better on embodied carbon. But reuse is not free, and the cost is concentrated in one place: the wash line uses potable municipal water, heats it with natural gas, and produces trade effluent.

That is the least green thing we do, it is unavoidable given what we are, and it is worth publishing the actual numbers rather than letting the good ratio do all the talking.

The water balance

The recovery loop is a three-stage cascade: the final rinse of one container becomes the second rinse of the next and eventually the first rinse of a third. Solids settle out between stages and are skimmed. Recovery averages 68 % across the line, which took four years and two rebuilds to reach.

The rainwater array covers about 22 % of what remains, averaged over a year — considerably more in a wet spring, close to nothing in a drought August. Net municipal draw is therefore about 13 gallons per container.

Setting it against the benefit

Reconditioning one container instead of manufacturing a new one avoids roughly 95 kg CO₂e. The wash costs about 19 kWh equivalent of gas, which is somewhere near 4 kg CO₂e, plus 13 gallons of municipal water and its associated treatment.

So the ratio holds comfortably — the wash costs a fraction of what manufacture would — but the effluent line is genuinely a debit rather than a credit. Manufacturing a new container does not produce trade effluent in Austin; reconditioning one does. We do not net that away and we do not pretend it is nothing.

What we have not solved

• The line is gas-fired. Electrifying it means either heat pumps that struggle at 160 °F or resistance heating with an electricity cost we cannot currently absorb. Both have been costed twice and neither works yet.
• Recovery has plateaued at 68 %. The next increment requires filtration rather than settling, and the capital does not pay back on our volumes.
• The concentrated effluent fraction has no beneficial use. It is discharged under permit. We would like it to be a feedstock for something and it is not.
• Drought years reduce the rainwater contribution exactly when municipal supply is most stressed. The array is least helpful when it would be most valuable, which is an uncomfortable irony.

None of those have a date attached, and we are not going to announce one until there is a real plan. Announcing intentions is the cheapest thing in sustainability reporting and the least useful.