Bridge-power units for telcos, data centers, and hospitals supply power for the brief interval between failure of the mains supply and the time that full backup power is available from fuel cells or generators. Traditionally, these have been flywheel-based. But a pair of new products from Maxwell Technologies stores energy in 22 2700-F ultracapacitors. This is Maxwell's first system-level product, complete with ultracapacitors, a dc-dc boost converter, dc charging circuit, cell balancing, and status indicators. The company's 1.6- and 2.3-kW PowerCache products provide 48-V power during startup or transfer to generators, microturbines, fuel cells, or other alternative primary or backup energy sources. Pricing is $7500 for single units. Contact the company for large-volume and OEM sales.