Back-up Power Supply

For more than a decade already, Nedstack fuel cell stacks have been used to power telecom stations worldwide. Our stacks are used by customers to build fuel cell systems to provide either continuous power supply, especially in remote areas without grid, or back-up power in areas with an unreliable grid. 

Backup power systems for Telecoms, Utilities and Railways are used to power electronic systems during grid power outages. Telecom companies, Utilities and Railways need to be able to rely on their backup systems. Until now battery packs (in combination with diesel generators) have been the most common solution to bridge temporary grid failures. Now, a better alternative is available: Nedstack PEM fuel cell powered backup systems.

A backup system energized with Nedstack PEM fuel cells offers high reliability and the lowest total cost of ownership. It compares favourably against alternatives on a range of measures:

Nedstack PEM FC Battery Diesel Gen-set
High reliability + +
Low initial investment + +
Low total cost of ownership +
Steady energy storage capacity + +
Guaranteed autonomy + +
Environmental sustainability + +

First and foremost, Nedstack PEM fuel cells are highly reliable. This means that in case of a grid power outage, your systems will continue to work, fuelled by our fuel cells. With the help of only a small battery, PEM fuel cells deliver instant start-up. They will continue to work as long as the hydrogen supply lasts. This supports the customer satisfaction you are aiming for, and it helps you avoid non-compliance penalties. Currently, over a 1000 fuel cell stacks have been supplied for commercial operations worldwide, both for back up and primary power applications. Some of these systems are turned on for short periods of time each and every day. This demonstrates the high reliability, efficiency, flexibility and long lifespan of Nedstack fuel cells.

Next to unfamiliarity, there is one other aspect slowing down the uptake of fuel cell systems: they still require a higher initial investment (CapEx) than batteries and diesel gen-sets. At Nedstack, we are working hard to further decrease our customer’s cost levels. Nedstack stacks are suitable for the lowest costs balance of plant components. Eventually, fuel cell stacks may become economically competitive from the start.

Despite their higher CapEx, backup power systems with Nedstack fuel cell stacks offer a lower cost of ownership than the traditional options. And isn’t it this total lifetime cost that actually counts? PEM fuel cells offer the following operational benefits, resulting it much lower operational costs (OpEx):

  • Fuel efficiency. PEM fuel cells operate at over 50% fuel efficiency, compared to a maximum of 35% fuel efficiency of internal combustion engines.
  • Fuel flexibility. PEM fuel stack systems can be made to operate on a wide range of fuels, enabling them to operate on the most cost efficient fuel available at your location.
  • Low system costs. Nedstack fuel cells are easy to integrate and offer low system component cost due to the efficient water cooling and operation at ambient pressure.
  • Low maintenance costs. Nedstack fuel cells are virtually maintenance free, other then the occasional replacement of air filters. Fuel cells have no moving parts that can break down or need to be replaced, unlike diesel generators. While battery life is unpredictable and therefore batteries need to be replaced every 3 to 5 years, Nedstack fuel cells offer long-term reliable outputs. Nedstack fuel cells can be equipped with a cell voltage monitoring (CVM) system. The CVM system allows an operator to remotely check the stack status in detail. Surprises are avoided. In the rare event that a stack needs to be replaced prematurely, the operator will know beforehand.
  • Easy cooling. Nedstack PEM fuel cells are water cooled, the output water of around 70 °C is easy to handle. As the fuel cell systems can operate at an electrical efficiency of around 50%, the amount of heat is comparable to the electric power generated. Water cooled stacks are more robust than air cooled ones, as they are less sensitive to air contamination. In addition the water cooling system can be built more compact and cheaper then air cooling systems at FC power output levels of above 1.5kW
  • Little risk of theft. Because of the expertise required to operate the systems, fuel cells and their fuel are less likely to be stolen than generators, diesel fuel, and batteries.
  • Limited space requirements. You will always find space to house a PEM fuel cell system. They operate both indoors and outdoors in a wide range of climates. They can be made very compact. A system (excluding hydrogen storage) can be placed in a standard 19” rack.

Find out how the total cost of ownership for fuel cells compare to batteries over time.
Over a 6-year period or longer, a fuel cell powered backup system is cheaper than a battery-operated one

A battery powered system (blue line) starts off cheaper than a fuel cell powered backup system (red line). However, over time, the total costs for a battery operated system are higher. Although the regular maintenance required greatly varies depending on the battery type, even low maintenance batteries, as plotted in the graph above, have higher maintenance costs than fuel cell systems.
For one, batteries continually need to be conditioned. Over time, that adds up. Month by month, the total costs of a battery system rise more quickly than that of a fuel cell system.

The big jump comes after 3 to 5 years (depending on the operating profile). The batteries will need to be replaced, while the fuel cells keep on working. Taking these replacement costs into account, it becomes clear that the fuel cell system is the more economic option.

As the years pass, batteries lose their capacity to store the original rated energy.. This decline in storage capacity is accelerated by the number of operating cycles and the amount of power that is withdrawn. Batteries also degrade faster due to temperature changes, which is why they should be kept in an air-conditioned space. The exact pace of degradation of batteries is neither predictable nor accurately measurable. To lower the risk of surprises batteries are preventively replaced at least every 5 years and more frequently depending on operating and risk profile. Nedstack PEM fuel cells continue to deliver steady voltage output over their full lifespan, while the energy storage is defined by the fuel tank size.

Contrary to battery powered backup devices, a fuel cell system does not need to be recharged. It will continue to run as long as the fuel supply lasts. This also means that fuel cell systems can be easily scaled to the number of backup hours required, simply by changing the hydrogen storage size. Fuel cell systems are by far the most cost effective solution to overcome long periods of grid failure. The remaining autonomy of the system (amount of fuel) can easily be monitored by measuring the hydrogen pressure. In the case of batteries it is virtually impossible to predict the remaining amount of energy.

PEM fuel cells convert hydrogen into energy, with pure water as their only by-product. Depending on the way the hydrogen is produced, our fuel cells have low to zero emission. This has obvious benefits for the planet, but it also has direct relevance for the day-to-day operations: indoor locations that are not suitable for a diesel gen-set, often can accommodate a fuel cell system. Additionally, PEM fuel cell systems have no moving parts. They do not cause vibrations or noise pollution. This has important health & safety benefits. Furthermore, Nedstack fuel cells are almost fully recyclable.