TUCSON ELECTRIC POWER CHOOSES CUTTING-EDGE TECHNOLOGY TO IMPROVE SYSTEM RELIABILITY EleQuant's Solution Cuts Man Hours, Provides Operational Flexibility

San Francisco, May 25, 2004

EleQuant Inc. today announced that Tucson Electric Power Company has chosen EleQuant’s unique software solution to improve the utility’s system reliability, reduce costs and improve staff productivity. Tucson Electric Power (TEP) is purchasing an off-line version of EleQuant’s Advanced Grid Observation Reliable Algorithms (AGORA™) software, cutting-edge technology that always gives power system operators reliable, accurate system information.

Currently, TEP manually creates system contingency plans which require thousands of engineering hours.

“Tucson Electric Power is growing and we needed a better way to plan for any possible problem with the system,” said Mike Flores, manager of operations for TEP. “EleQuant’s solution will give our company the reliability and flexibility we need to provide our customers with consistent, high-quality service, while optimizing the company’s energy costs.”

For more than 40 years, most U.S. utilities and other energy organizations, including TEP, have analyzed their electrical power system by using a mathematical technique for calculating power flows, known as the Newton-Raphson method. Power-flow tools that are based on Newton-Raphson will provide an approximate answer, but often don’t provide any answer, even though one exists. - more -

The AGORA software is based on the most notable advancement in power engineering technology in decades—a deterministic, non-iterative method of calculating power flows in a transmission system. EleQuant’s solution will never provide an incorrect solution to the power flow calculation, and will always find the solution when one exists.

The AGORA off-line product allows TEP to completely automate the creation of the company’s “Local Must Run/Load Shed Tables,” contingency plans designed to anticipate a variety of system problems.

“Utilities around the world are discovering that EleQuant’s solution provides unparalleled reliability for both normal operations and when a disturbance or collapse occurs,” said Regina Llopis-Rivas, EleQuant's CEO. “We are delighted that Tucson Electric Power has chosen EleQuant’s technology to improve their system’s dependability.”

The EleQuant and TEP partnership is the first of a two-phase implementation plan. The second phase will result in an on-line system that automatically creates the table information based on real-time information. Tables would be created dynamically depending on the load and generation conditions, allowing TEP to respond immediately to any system changes. About EleQuant

EleQuant is a wholly-owned subsidiary of the Barcelona, Spain-based technology and software development company, GRUPO AIA. Specializing in solving complex problems for the energy, banking and telecommunications industries, GRUPO AIA is known throughout Europe for developing innovative solutions in areas such as intelligent observation and management of electrical grids, electricity demand forecasting, and river basin hydro-generation optimization.

In 2002, the company launched its U.S. operations with the formation of EleQuant, headquartered in San Francisco. EleQuant provides the company's energy products to utilities, independent system operators, regional transmission operators and other organizations involved with management of electricity grids in the U.S. and Canada. To learn more about EleQuant, visit www.EleQuant.com..

About Tucscon Electric Power

Tucson Electric Power is Arizona’s second largest investor-owned utility and serves more than 360,000 customers over a 1,155 square-mile service territory in the southern part of the state. TEP is the principal subsidiary of UniSource Energy Corporation.

To learn more about TEP, visit www.tucsonelectric.com . # # #