Senior management with the Omaha Public Power District in Nebraska recommended that the utility build between 400 MW and 600 MW of utility-grade solar — a capacity addition that would exponentially increase the state's solar capacity — with natural gas for backup generation.
Solar capacity additions of that magnitude likely would catapult Nebraska considerably higher in the national rankings. As of the close of the second quarter, Nebraska had 45.23 MW of installed solar capacity, ranking it 44th of all U.S. states, according to the Solar Energy Industries Association. By comparison, Pennsylvania ranked 22nd, with 452.24 MW of installed solar capacity.
The proposal from the Omaha Public Power District, or OPPD, also includes replacing some of the utility's retiring coal capacity with natural gas. The utility further said it may add voltage-support devices as necessary.
At the OPPD's North Omaha Generating Station, three previously coal-fired units already have been converted to natural gas. Those three units will no longer be operational by 2024, before which point the remaining two units at the facility will be converted to natural gas.
"The recommendation of our team comes after thoughtful and careful analysis of available technologies, affordability of options and what solutions might best fit our needs," OPPD President and CEO Tim Burke said in a statement.
As a result of that analysis, the OPPD ruled out certain technologies such as combined cycle, wind turbine, and new nuclear or coal baseload over concerns of "significant cost premiums, comparative ineffectiveness, or failing to meet technical or resiliency requirements," Mary Fisher, the OPPD's vice president of energy production and nuclear decommissioning, said in a presentation.
Battery storage also would not be pursued, partly due to a lack of policy guidance regarding whether the Southwest Power Pool would consider battery storage accredited generation capacity and partly because the utility said it is "not a technical solution for multi-day resiliency events" such as tornadoes or ice storms.
The OPPD estimated that as a result of its resource decisions, it will see a 30% reduction from its 2010 carbon dioxide emission levels by 2024.
Public comments on the plan will be accepted through Nov. 8, and the OPPD's board of directors is expected to vote to authorize the negotiation of procurement contracts at a meeting later that month. According to Fisher's presentation, the OPPD anticipates that construction on the new facilities could occur between 2020 and 2023.