Leading Wind Contractor to build its 27th project in the Lone Star State.

Minneapolis, MN April 30, 2015

Mortenson Constructions Wind Energy Group today announced that it entered into a contract for construction of the Shannon Wind Project located near Windthorst, Texas, which is owned and managed by Alterra Power Corp. (Alterra). Vancouver-based Alterra acquired the project from Horn Wind, LLC, a north Texas wind developer that has successfully developed two other wind projects in the region - both constructed by Mortenson. This will be the second wind farm Mortenson will construct with Alterra following the completion of the Dokie Wind Project located in Chetwynd, British Columbia, in 2011.

Mortenson will be responsible for the construction of the access roads, foundations, turbine erection, underground electrical collection system, substation and transmission line installation. The 204 MW project will utilize GE turbines, and at completion will deliver power sufficient for approximately 61,000 households.

Mortenson commenced construction on the project under a limited notice to proceed in 2013 and completed a number of foundation excavations and carried out site road construction in both 2013 and 2014.

Approximately 250 jobs will be created during the construction, and millions of dollars will be infused in the local community and surrounding areas as a result of construction spending and living expenses from Mortenson crews and trade partners.

"We are very excited to again partner with Alterra," stated Tim Maag, vice president and general manager of Mortensons Wind Energy Group. "We are honored to play a part in the growth of their business and expansion into the United States while also continuing to expand our local presence."

To date Mortenson has completed construction on 26 wind projects and three solar facilities across Texas. In 2014, the company established an office in San Antonio dedicated primarily to energy and infrastructure.

"We are very happy to work with Mortenson on our first U.S. wind project and appreciate the depth of experience they bring to the table," said Paul Rapp, VP Wind and Geothermal Power for Alterra.

Construction on the Shannon Wind Project is expected to be completed in late 2015.

About Mortenson Construction
Founded in 1954, Mortenson Construction is a U.S.-based, family-owned construction company. Ranked as the 25th largest contractor in America, according to Engineering News-Record, Mortenson provides a complete range of services, including planning, program management, preconstruction, general contracting, construction management, design-build and turnkey development.

Since entering the renewable energy market in 1995, Mortenson Construction has become the leading builder of wind power facilities in North America having constructed more than 140 wind projects throughout the United States and Canada. In addition to wind farms, Mortensons Renewable Energy Groups also construct solar and high voltage transmission and distribution facilities. Mortenson has offices in Chicago, Denver, Milwaukee, Minneapolis, Phoenix, Seattle, San Antonio and Toronto. For more information, please visit http://www.mortenson.com/wind.