May 21, 2002 — Avista Labs, a wholly owned subsidiary of Avista Corp., and a developer and manufacturer of proton exchange membrane (PEM) fuel cells, recently announced it has been awarded a patent further protecting its claims of modularity in fuel cell system construction.

“This new patent adds substantially to the value of our company,” said J. Michael Davis, CEO of Avista Labs. “The key to reliability in fuel cell systems is in a modular approach. When other fuel cell developers build systems that use fuel cells or balance of plant components in modular configurations, this patent may require a licensing agreement with us.”

Avista Labs is a pioneer in building PEM fuel cell systems using a modular approach. Avista Labs fuel cells are easily replaceable plastic cartridges. Because the cartridges are air-cooled and hot-swappable and can be selectively activated or deactivated, they are inherently more reliable than other PEM fuel cells. And while Avista Labs already holds patents for its own Modular Cartridge Technology™, this new patent covers any type of fuel cell system that utilizes multiple fuel cell modules to enhance reliability, according to Davis.

This new patent is the fifth patent issued to Avista Labs. It includes 300 claims covering certain basic control and balance-of-plant systems when used in a modular or multiple fuel cell system. Avista Labs has 22 additional patents pending, covering various technologies relating to its fuel cell design and operation.

Avista Corp. is an energy company involved in the production, transmission and distribution of energy as well as other energy-related businesses. Avista Utilities is a company operating division that provides electric and natural gas service to customers in four western states. Avista’s non-regulated affiliates include Avista Advantage, Avista Labs and Avista Energy. Avista Corp.’s stock is traded under the ticker symbol “AVA” and its Internet address is