Renewable natural gas production is growing faster than the market can absorb, but ethanol plants that burn natural gas for process heat can't use RNG's environmental value to cut their carbon intensity. The reason isn't technical. Book-and-claim accounting is already accepted for RNG under California's Low Carbon Fuel Standard and for renewable energy credits under 45Z, yet the same framework doesn't apply to renewable thermal credits at an ethanol facility. That mismatch matters because ethanol plants are large natural gas consumers, and RNG developers are facing oversupply. Allowing book-and-claim for process heat would create a new source of demand without requiring pipeline modifications. The metering and verification infrastructure already exists. The remaining barrier is regulatory: process energy at ethanol plants simply hasn't been added to the list of recognized uses. Closing that gap could lower ethanol's carbon intensity and help absorb excess RNG.
