45Q & Carbon Economics

THE CARBON
CAPTURE
OPPORTUNITY

Regulatory changes have dramatically improved the economics of carbon capture for compression operators. E4's ECC system is positioned to make capture financially compelling at mid-size stations — not just large industrial facilities.

REAL REVENUE
FROM CAPTURED
CARBON

The Inflation Reduction Act significantly expanded the 45Q tax credit program — raising per-ton credit values and lowering the minimum annual capture threshold from 500,000 metric tons to just 12,500 metric tons. This change makes E4's ECC system economically viable at compressor stations that would never have qualified under prior rules.

CO₂ captured from engine exhaust is classified as anthropogenic — the same CO₂ that was always going to atmosphere — making it fully eligible for 45Q credits. This also counts toward Scope 1 and Scope 2 carbon reduction commitments.

45Q Tax Credit Schedule (IRA)

Enhanced Oil Recovery (EOR)$60/ton
Geologic Sequestration$85/ton
Prior Minimum Threshold500K tons/yr
New Minimum Threshold (IRA)12,500 tons/yr
ECC Capacity (15k hp station)75,000 tons/yr

THE BETTER
ECONOMICS

Electric drive conversion is the most commonly discussed decarbonization path for compression. But peak demand charges — rarely factored into front-end economics — can dramatically increase operating expense, and the capital required to replace the engine plus connect grid infrastructure is substantial. And it generates no credit revenue.

Capital Efficiency vs Electric ConversionHigh
45Q Credit EligibilityFull
Scope 1 & 2 ReductionBoth
Retrofit ComplexityLow
Operational DisruptionMinimal
Side-by-Side Comparison

ECC vs ELECTRIC
CONVERSION

E4 ECC System Electric Drive Conversion
Existing engine replacementNot requiredRequired
Grid infrastructureNot requiredRequired
45Q carbon credit revenueYes — up to $85/tonNone
Electricity cost exposureNoneOngoing — plus peak demand charges
Waste heat power generationIntegrated motor-generatorNot applicable
Scope 1 reductionYesYes
Scope 2 reductionYesDepends on grid source
Operating expense trendImproved (credits + efficiency)Increases (electricity cost)
Installation complexityAnalogous to waste heat recoveryMajor civil & electrical work

NFG PILOT
PROGRAM

The ECC system pilot is being conducted with National Fuel Gas at an active compressor station — collecting real-world data across all key performance dimensions.

  • System design complete, patent awarded April 2023
  • CO₂ process modeling complete
  • Design complete for manufacturing of test skid
  • Component testing designed and ready to begin
  • Pilot skid design completed as full working system
CO₂
Removal rate & purity measured at actual compressor station
kW
Electric generation from waste heat quantified
psi
Processed CO₂ condition documented
η
Overall system efficiency across all operating modes