Columbus, Ohio, July 1, 2010 — Electric Transmission America, a transmission joint venture between subsidiaries of American Electric Power and MidAmerican Energy Holdings Co., released Phase One of a study of the transmission needed in the Upper Midwest to support renewable energy development and to transport that energy to load centers.

ETA sponsored the study along with American Transmission Co., Exelon Corp., NorthWestern Energy, Xcel Energy, and MidAmerican Energy Co., a unit of MidAmerican Energy Holdings Co.

The Strategic Midwest Area Transmission Study sponsors retained Quanta Technology to evaluate extra-high voltage transmission alternatives for new transmission development in the Upper Midwest.

In Phase One, Quanta evaluated eight transmission alternatives designed to support the integration of 56.8 GW of nameplate wind generation within the study area, including North Dakota, South Dakota, Nebraska, Minnesota, Iowa, Missouri, Wisconsin, Illinois, Indiana, Michigan and Ohio. This translates into enough energy to power more than 15 million households.

The study's Phase One results recommend three alternatives for further study based on a rigorous reliability assessment and stakeholder input. One of the alternatives is primarily 765-kilovolt (kV) EHV transmission, another includes 765 kV combined with limited use of high-voltage direct current transmission lines, while the third constitutes a combination of both 345-kV and 765-kV transmission lines. The three alternatives will be evaluated further during the second phase of the study, scheduled for completion during the third quarter of 2010.

The SMARTransmission Study's goal is to develop a 20-year transmission plan that ensures reliable electricity transport, provides an efficient transmission system to integrate new generators and foster efficient markets, minimizes environmental impacts, and supports state and national energy policies and goals. The study was designed to incorporate a high level of stakeholder input.

Throughout the study process, the SMARTransmission sponsors held open meetings where interested stakeholders had the opportunity to participate and provide input into the direction of the study. Participants representing investor-owned utilities, commissions, the Federal Energy Regulatory Commission, municipalities, wind developers and others have participated in the open meetings.

In addition, the SMARTransmission sponsors regularly met with representatives from the Midwest Independent Transmission System Operator, PJM Interconnection, the Mid-Continent Area Power Pool and the Southwest Power Pool.

ETA is a joint venture between subsidiaries of AEP and MidAmerican Energy Holdings Company to build and own electric transmission assets. The joint venture is a 50-50 partnership organized to identify and invest in high-voltage transmission projects (345 kV or higher) located in North America outside of the Electric Reliability Council of Texas.

The two companies also have an existing joint venture agreement to build transmission in ERCOT. ETA's current joint venture projects include Prairie Wind Transmission in Kansas and Tallgrass Transmission in Oklahoma.

AEP, headquartered in Columbus, Ohio, is one of the largest electric utilities in the U.S., delivering electricity to more than 5 million customers in 11 states. MidAmerican Energy Holdings Company, based in Des Moines, Iowa, is a global provider of energy services to more than 6.9 million customers worldwide.