Overcoming Barriers to Fuel Cell Deployment

Rooftop Backup Power

Rooftop cell tower siting has contributed to improved cellular reception and service for millions of consumers around the world.  While the advantages of a rooftop installation can be compelling, there are logistical problems that come to play when deciding which power backup system is best deployed to keep the site up and running during prolonged grid outages.

  • Physical space requirements
  • Setbacks related to fire code compliance
  • Floor loading
  • Noise & emission restrictions
  • Fuel provisioning

Fuel Cell Solution

A PEM fuel cell system provides a compelling alternative compared to both diesel and battery backup power systems, offering economic, emission, noise, reliability and space advantages. A typical PEM fuel cell usually weighs under 680 kg compared to 2,300 kg for the alternatives.  However, when powered by compressed hydrogen from standard commercial cylinders, the weight of the hydrogen cylinders becomes the problem. Servicing a 5-kW load for 72 hours typically requires 48 steel cylinders, plus steel racking for the cylinders which can weigh about 5,000 kg possibly triggering structural modifications. The setback requirements for compressed hazardous gas will compound the space requirement barrier.

S-Series Hydrogen Generator

Integrating e1’s S-Series hydrogen generator with the fuel cell reduces the fuel cell solution’s weight and setback requirements making the fuel cell solution competitive with legacy battery and diesel solutions. Compared to using compressed hydrogen cylinders for a typical 48-hour backup solution, the S-Series significantly reduces the floor loading of the fuel cell solution by up to 80%, and the physical space requirements by up to 95%, releasing the full potential of the fuel cell solution for rooftop applications.

Reduce total weight of floor loading

Reduce physical space requirements

Compressed Cylinder
H2 Solution
S-Series H2 Solution
with Fuel Cell
Physical Area 4.5 m2 (48-pack) 3.7 m2
Area with setbacks 70 m2 3.7 m2
Weight of Fuel Cell 680 kg 680kg
Weight of H2 Solution 5,000 kg 450 kg
Total Weight 5,680 kg 1,130 kg