What is a Bloom Energy Server and how does it work? How does a Bloom system compare to other fuel cells?
A Bloom Energy Server is a commercial fuel cell product that has captured the attention of retail and industrial giants.
The push for virtualization and consolidation may have eased the growth in data center energy demands, but power is still an increasingly costly and delicate commodity. Organizations anxious to mitigate their dependence on public power grids and explore power cogeneration options are considering fuel cell-based generators that convert clean, often renewable, fuels into electricity. Even Apple has integrated Bloom boxes for its data center facility in Maiden, N.C.
A Bloom box is basically a fuel cell that uses an electrochemical process to convert fuel into electricity -- similar to the architecture of a battery. Bloom's process uses a solid ceramic electrolyte placed between simple ink-based anode (positive) and cathode (negative) electrodes. When air, fuel and heat are provided, the fuel cell converts the fuel into electricity, with by-products of heat (which keeps the process running), water and some carbon dioxide. The process continues as long as air, fuel and heat are available.
Each Bloom Energy Server is made up of thousands of individual fuel cells. Each fuel cell produces about 25 watts. The fuel cells are then sandwiched together to make a stack, which has about enough power for a suburban house. The stacks are then interconnected to create a module, and the modules are assembled into a complete Bloom Energy Server. The individual server produces 200 kW of energy, so larger facilities will want to combine multiple servers. A 10 MW data center facility, for example, requires 50 Bloom Energy Servers.
Fuel cells are not new; the technology has been available for about 100 years. But the materials and chemicals have generally been too expensive and potentially dangerous to make general deployment attractive for business and industry -- some fuel cells use phosphoric acid. Bloom claims the inexpensive materials and more than 50% electrical efficiency in their solid oxide fuel cells (SOFCs) have made the technology practical for general-purpose deployment, and major companies like Apple, WalMart, Staples and others have incorporated Bloom products at one or more facilities.
This was first published in May 2013