How many Bloom boxes does it take to power a data center? How reliable are these systems?
A Bloom box, officially known as a Bloom Energy Server, produces 200 kW of energy and connects to a grid with other units to provide the energy demands of any given installation. Two units provide 400 kW, three units provide 600 kW and so on.
The number of solid oxide fuel cell (SOFC) users is growing as electricity prices climb (especially in densely populated regions) and renewable energy initiatives take hold within the corporate culture. Many current users deploy two or three units to provide up to 600 kW. Larger users include the biotechnology firm Life Technologies in Carlsbad, Calif., and Caltech in Pasadena, Calif., which deploys enough Bloom units to provide 2 megawatts of energy.
There are other potential advantages to SOFC deployment. Generating electricity on-site reduces transmission losses from the power plant to the site. And because electricity is produced constantly, it could eliminate other forms of backup power, such as costly uninterruptible power supplies and diesel-powered backup generators, as well as the switching gear needed to integrate backup power into the data center.
However, reliability is a significant consideration in SOFC deployment. Bloom claims customers such as Staples have experienced availability of more than 99% with its Bloom Energy Servers, but fuel cells require a constant source of fuel to function, so shops must determine contingencies if disruptions to natural gas or biogas sources occur. In many cases, the organization will fall back to the commercial power grid for the duration of the fuel outage.
Data centers and many large-scale commercial and industrial businesses are increasingly concerned with the spiraling cost of electricity generation and reliable delivery across aging, often-overloaded infrastructures. Companies are exploring cogeneration technologies, and fuel cell systems such as the Bloom box have emerged as a platform for reliable, long-term local electricity generation using renewable fuel sources such as biogas, a methane-rich gas produced from decay in swamps, marshes, landfills, sewage and manure.
This was first published in May 2013