Most organizations rely upon diesel to fuel their backup critical power systems. Few however are aware that recent government mandates reducing the environmental burden of diesel directly impact their ability to provide uninterrupted power. Diesel can no longer sit unmanaged until backup generators are required in emergencies as the case has traditionally been. The introduction of ultra low sulphur diesel (ULSD) and biodiesel blends result in a fuel which absorbs more water which leads to an array of problems. Water causes corrosion and filter issues, to entire systems not functioning when most needed.

Changes in Diesel

Historically, sulphur content in diesel in North America and the European Union either had no restrictions or was limited to 2,000 parts per million (ppm). Following 2007, sulphur limits became as low as 10 to 500 ppm, depending on intended use and location. The process of removing sulphur from diesel to create ULSD can reduce lubricating characteristics in the fuel. To compensate, oil refiners include additives to most fuel produced. Biodiesel is included in diesel in the European Union (5% to 7%), Canada (2%) and by region in the United States, up to 5%. Most of these additives, including biodiesel, increase the fuel’s ability to absorb water.

Industry Perspective

The Uptime Institute is a third-party data center research, education, and consulting organization located in New York City. In their 2010 report Biodiesel, the organization recognized issues brought forward by the introduction of ULSD, mainly that the fuel holds more water and noting the associated issues regarding water contamination. Subsequent concerns brought forward about the introduction of biodiesel by their members centered on the accumulations of water and associated problems. The institute went on, stating that “any of these issues put at risk a data center’s capability to meet continuous availability requirements.” Data centers and other critical power applications now must proactively manage their fuel stocks, implementing a comprehensive fuel management strategy.

Risks associated with modern fuel

Unmanaged water in fuel causes issues at every step of the fuel cycle from distribution, through storage and eventual use. Water absorbed in fuel is causing greater corrosion in tanks reducing operating life and risking environmental incident. Microbial activity causing degradation of the fuel and filter blockage, risking operational security. Finally, water injected into the engine causing severe mechanical damage, corrosion, and additional maintenance. All of these factors risk downtime and inoperability.

Fuel Management Strategy

The implementation of a comprehensive fuel management strategy ensures protection of critical power investments.

•  Begin by evaluating your tank set up; consider the impact of likely site temperatures and humidity ranges.
• The next step is to know what type of fuel you are using. Regular testing of the fuel warns of contamination.
•  Implement a fuel polishing system with coalescing filters proven to remove emulsified water(water suspended within the fuel). Ensure the system is certified to SAE J1488: 2010 to ensure you’re dealing with emulsified water

These simple steps will ensure investment protection, reduced maintenance, and maximise emergency power availability.