Selection of Diesel Generator Sets in the Data Center Industry

The energy consumption of data centers originates from IT equipment, lighting, cooling systems, and power distribution systems. Power supply reliability is critical for data centers. Diesel generator sets, as essential backup power equipment, can take over power supply during grid power failures, thereby preventing significant losses caused by server downtime or data loss. Below is an overview of diesel generator selection in the data center industry.

Generator power ratings selection

As key standards for diesel generator sets, ISO 8528-1 and GB/T 2820-1 define four types of generator power ratings:

Continuous Operating Power (COP)

Prime Rated Power (PRP)

Limited-Time Prime (LTP)

Emergency Standby Rating (ESP)

The generator power rating selected should be based on actual operating conditions. Choosing the right generator significantly impacts both the investment and power supply reliability of a data center. Different clients may select generator power ratings flexibly based on their specific requirements.

Cummins Power Generation pioneered the DCC (Data Center Continuous) power rating in the industry, tailored to the continuous power supply needs of data centers. This rating provides significant value for data center investment and operational management. The DCC power rating is recognized by Uptime Institute and can be used for Tier III and Tier IV certifications.

Key considerations for data center generator sets

The engine, which provides the necessary power for the generator set, is the most critical component in the selection process.

Primary consideration: Sufficient power output and dynamic response to load changes.

Due to the complexity of designing and manufacturing large-capacity diesel engines, engines from different manufacturers may vary significantly. Ensuring sufficient power output is a primary consideration, followed by the engine’s dynamic response to load fluctuations.

Trends: Small displacement with high power output.

Advances in technology have driven diesel engines toward smaller displacements and higher power outputs. Manufacturers are enhancing engine power density through innovations such as turbocharging and high-pressure clean combustion technologies. Traditional naturally aspirated engines, whose power output was proportional to displacement, are now obsolete. Key methods to improve power density include increasing air intake, optimizing mechanical efficiency, and improving combustion efficiency.

Four key factors when selecting a diesel generator for data center:

Adequate power output for requirements.

Superior dynamic performance—ability to handle single-step full load application.

Electronic fuel injection (EFI)—better load-handling characteristics.

Generator manufacturers with proven application experience and extensive case studies.

In addition to the considerations above, other factors such as harmonic loads, capacitive loads, rapid parallel system capability of genset, high-voltage generator neutral grounding, and ventilation systems should also be taken into account.

Fuel tanks and supply systems

Fuel tank capacity and design of generator sets comply with technical specifications and fire safety codes. Key requirements include:

Underground tanks: High-quality steel with anti-corrosion treatment, continuous magnetic float level sensors (4–20mA output to PLC).

Day tanks: Access covers, inlet/return/drain/overflow pipes, magnetic level gauges with local/remote (4–20mA) signals.

Fuel transfer pumps: Dual pumps with filters, check valves, and explosion-proof motors (3-phase, 50Hz, overload protection).

Control systems: Monitor tank levels, control valves/pumps, provide alarms, and integrate via Modbus-RS485.

Load bank testing

Load testing is vital for verifying generator performance during project acceptance. It validates full-load output, ventilation, exhaust, fuel supply, and electrical system design. Regular generator load bank testing during maintenance prevents issues like carbon buildup from light-load operation, ensuring long-term reliability of diesel generators.

This structured approach ensures diesel generator sets meet the stringent demands of modern data centers, balancing power reliability, efficiency, and operational safety.

Looking for a reliable power generator? Contact us today to order the right generator for your needs.