Though Cummins' engine factory in England is running at full output, customers have to wait up to three months for delivery. Demand for Caterpillar generators has been growing at 20 percent per year, and much of that demand is coming from Internet-related businesses. Although Internet data centers are spending heavily on generators, the owners of the expensive machines hope they never have to use them. Electricity produced by on-site diesel generators can cost three times as much as power bought from the grid. But data center owners have few choices.
Fuel cells are still too small and too expensive.
Small natural gas turbines are becoming more common, but have yet to capture significant market share. Indeed, backup power equipment has become as essential as fiber-optic cable. Power supply plays a very big part of that. The power redundancy provided by the diesels is one of the most expensive parts of a data center, Moore said. They simply have to have the horsepower to keep the lights on.