Back-up Diesel Generators and Stored Fuel

The importance of diesel generators is well known by the facilities and IT personnel of a data center, especially in the event of a power failure. Due to this fact, much emphasis and resources are put into the generator's physical maintenance, but - much too often a very important factor is neglected, the on-site diesel fuel storage.

The stored fuel used to power the diesel generators can easily deteriorate in many ways - water being the most common, usually from condensation or micro-bacterial growth which can build up in the fuel and lead to a sludge formation and eventually sediment. These various contaminants will clog up filters, reduce the fuels performance and lead to expensive damage or loss of power when diesel generators are needed to power your critical load. This can become a single point of failure even if you have redundant generators.

To prevent this point of failure, stored fuel must be tested on a regular basis. If contaminants are found, use a fuel polishing system to filter out all of the contaminants. Newer data center sites are starting to install permanent fuel polishing system devices. If there is not a permanent device on site, another solution is to call your local fuel provider and inquire about a portable unit brought on-site to clean up your fuel if problems are discovered. The frequency of cleaning depends on many factors but having regular testing, several times per year can alert you to any problems before they turn into an outage.

Remember - the fuel supply to your diesel generators is every bit as important as all of the other maintenance on the generators.

Ken Koty