Cost

Below is a rough break-down of costs by category, with comments. All figures are approximate.

Labor is not included, because it is so variable. For example, there is very little electrician time needed to hook up the fuel cell. Putting together a full solar power system takes much more electrician labor, but it does not go into the hydrogen part of the system. Plumbing can be farmed out, or you can do it yourself. The metering hook-ups present a similar choice. In all cases you should be sure work is to code and permitted.

Gas:

  • Commercial hydrogen (per rental K-cylinder): $60.
  • Commercial nitrogen (per rental K-cylinder): $30. You need 6 to 8 cylinders to purge a 500 gallon tank.
  • Regulators for K-cylinders: $240 each (you need one for N2 and one for H2).

Fuel Cell:

  • ReliOn 1 kW unit: $6500. The price has not dropped much in the past few years.
  • Various 5 kW units: $15,000.
  • ReliOn data logging software: $500.

Electrolyzers:
Hogan GC-600: $7,900 per unit. As mentioned, there are better choices for this job.


Balance of Plant:

  • De-Ionizer unit for electrolyzer: $1300.
  • ReliOn Indoor Installation Package: $3000. Includes wing, manifold, panel, H2 sensor, and solenoid valve.
  • Re-calibrating H2 sensor: $75 (sent to factory) or $500 for on-site kit. We are testing an alternate, home-brewed method.

Remote Operations:

  • PLC (programmable logic chip) package for remote op: $500.
  • Brand monitoring package (meter plus 9 shunts): $2000.

Hydrogen Piping:

  • Stainless steel tubing, 1/4″: $$1.70 per foot.
  • Stainless steel tubing, 3/8″: $2.00 per foot.
  • pressure transducer: $250.
  • pressure gauge: $150.
  • Stainless fittings, Swagelok brand: $10-30.
  • Stainless valve, Swagelok brand: $150.
  • Our total cost for stainless fittings: $2600. This would have been much lower if we had used more Parker fittings, since they are markedly less expensive.

Storage Tank:

  • New 500 gallon propane tank: $1200.
  • Pressure relief valve for tank: $100.
  • Stainless steel tubing, 1″, to elevate relief valve: $9 per foot, 20′ min. A relief valve threaded at both ends would save the cost of this tubing.

PV Array and Inverter:

  • 10 x 165 Watt panels: $7500.
  • Rack for panels: $1300.
  • Outback off-grid package: $4600. Includes inverter, AC and DC panels, charge controller, control panel, other misc. This is not a formal package; it is most of the gear for an off-grid system.
  • Not included: Wire, breakers, conduit, etc.

Batteries:

  • L-16 battery: $200 each.
  • Bank of 30 L-16’s: $6000. Same effective storage as a 500 gallon H2 tank.
  • Bank of 60 L-16’s: $12,000. Same effective storage as a 1000 gallon H2 tank.

Assuming you have an off-grid system (PV array, inverter, some batteries), you can compare costs of a hydrogen system vs. battery storage. Telecoms companies have found that the larger their power storage needs, the more competitive hydrogen becomes. This is why they use fuel cells for their back-up power. However, they use commercial hydrogen. Making your own H2 has additional costs, including the need for more solar panels because of system inefficiencies. On the other hand, commercial hydrogen is not at all carbon-neutral, while home-made hydrogen is. In general, a system like ours will cost more than a monster battery bank and Honda generator. But it’s also way cooler.