Hydrogen vs. Diesel Backup Cost

Grid planners and facilities teams can quickly see whether hydrogen fuel cells or diesel gensets deliver the cheaper run cost for a specific outage window. Enter the critical load and autonomy, then adjust fuel pricing and conversion efficiencies to compare total fuel spend and quantities required.

Average power draw that must be supported during an outage.
How long the backup system must operate at the stated load.
Defaults to $4.25/gal for delivered ultra-low sulfur diesel.
Defaults to 13 kWh/gal for mid-sized Tier 4 generators.
Defaults to $8.00/kg for green hydrogen delivered at 350 bar.
Defaults to 50% LHV-to-AC efficiency for PEM fuel cells.
Defaults to 33.3 kWh/kg lower heating value.

Examples

  • 450 kW load for 10 hours, defaults for fuel pricing and efficiencies ⇒ Need 4,500 kWh. Diesel burns 346.15 gal costing $1,471.19, while hydrogen needs 270.27 kg costing $2,162.19.
  • 120 kW load for 6 hours, diesel at $3.80/gal, hydrogen $6.50/kg, 55% fuel-cell efficiency ⇒ Diesel fuel $210.46 vs. hydrogen $853.66.

FAQ

Does this include capital costs?

No. The calculator isolates variable fuel spend. Add amortized CapEx separately to reflect total cost of ownership.

Can I model blue or grey hydrogen?

Yes. Override the hydrogen price per kg with the delivered rate for your specific supply contract.

What about emissions comparisons?

Pair the fuel quantities with emissions factors—such as 10.21 kg CO₂/gal for diesel or supplier EPDs for hydrogen—to understand carbon intensity.

Additional Information

  • Diesel efficiency is simplified as net AC kWh per gallon; adjust upward for newer generators or downward for part-load derates.
  • Fuel-cell efficiency multiplies the hydrogen energy density (lower heating value) to convert kg into delivered AC kWh.
  • Use the fuel quantity outputs to size onsite tankage, delivery cadence, and permitting thresholds.

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