Converting Data Centers From Diesel To Gas Power Generation

Marcelo Algrain, Ph.D.
Senior Engineering Technical Steward
Caterpillar Inc. Electric Power Division

October 2016

INTRODUCTION

The energy needs of the data center (DC) industry continue to grow at a brisk pace. In the past, preferred DC locations were near inexpensive, reliable power sources. Today, such locations are more difficult to come by, and pressure is mounting to find alternate solutions that will be less demanding on the grid, particularly when electrical demand is high.

Despite many DCs having sufficient self-generation capacity from their diesel standby units, the viability of running those units to relieve the grid is neither economically feasible (operating cost would be prohibitive due to high cost of fuel) nor allowable by current air board restrictions that put limits on yearly hours of use. The function of diesel emergency units is purely for backup power at the DC during utility outages.

On the other hand, gas-based generation has a much lower environmental impact and the cost of fuel is significantly reduced compared to diesel power generation. Additionally, some utilities provide financial incentives to reduce consumption at times of grid congestion. Under these conditions, it becomes economically and environmentally viable for a DC to use gas generator sets for cogeneration during non-emergency periods. How much cogeneration would be needed depends on specific scenarios, but it could be as little as supporting noncritical loads to powering the entire DC facility.

It is needless to say that for an industry that must provide the highest level of resiliency, the idea of switching from diesel power to gas power would be a technical leapfrog that may be viewed by some as too radical. If so, an evolutionary approach through incremental steps may be preferable.

The DC transition from diesel power to gas power could be achieved in a number of ways. A few options are outlined below. Note that even solutions that would be generally unattractive could be the right solution in special cases.