Calculation: Hydrogen Fuel Credits
This calculation assumes a fueling station owner sells 255,500 kg of hydrogen per year, a H2 carbon intensity of 76.10 gCO2E/MJ (produced from on site reforming with renewable feedstock), Table 3, and a State carbon fuel standard is 91.31 gCO2E/MJ.
Note: CI = Carbon intensity.
In this example, it’s estimated the station serviced 1,278 FCEV during the year; each car goes an average 12,000 miles per year at an average range of 60 miles per kg of hydrogen:
1,278 FCEV = [(255,500 kg per yr. x 60 miles per kg) / 12,000 miles per yr.].
On a per car basis, 1,073 carbon credits equates to approximately 0.8 credits per car:
0.8 credits per car = (1,073 credits / 1,278 FCEV).
A regulated hydrogen gas station owner only accrues credits, should credits be available, when pumping hydrogen produced on-site reforming with renewable feedstock. Only in this case is the CI of the alternate fuel less than the state standard, i.e., 76.10 versus 91.31, Table 3.
All other methods to produce hydrogen have CI values higher than the state standard, Table 3. These methods include; compressed H2 gas from central reforming of natural gas (NG), liquid H2 from central reforming of NG, and compressed H2 from on-site reforming of NG. See California’s Intensity Lookup Table for Gasoline and fuels that Substitute for Gasoline for a comprehensive list of Cl values for gasoline and a host of alternate fuels.
Looking at all possible scenarios, the impact of the State CI standard is:
Credit Situation: CI of Alternative Fuel is lower that the State’s CI Standard
- A higher State standard would generate more carbon credits.
- A lower State standard could turn the credit into a deficit situation.
Deficit Situation: CI of Alternative Fuel is higher that the State’s CI Standard
- A higher State standard could turn the deficit into credit situation.
- A lower the State standard would generate more carbon deficits.
Furthermore, the number of credits or deficits accrued derives from the quantity of alternative fuel supplied; gallons, kg or kWh, Step 1. Regardless of the CI value, if the alternative fuel is more efficient than gasoline than either more credits or less deficits will accrue
Moving over to EVs for a comparative credit of deficit assessment, the Tesla Model S serves as the quintessential example for consumer appeal and range, miles per charge. A Model S fitted with an 85 KWh battery requires around 93.5 kWh of electricity to charge from 0% to 100%, including on-board charger losses of about 10%. Tesla claims an estimated range of 300 miles at 55 MPH with the 85 kWh battery.
