Rochester Public Utilities Explains January Power Grid Emergency

Rochester, MN (KROC-AM News) - Warnings in recent years about the potential for rolling blackouts impacting Rochester and the entire Upper Midwest came close to reality during a bitterly cold weekend in January.

Rochester Public Utilities General Manager Tim McCollough joined Andy Brownell for Rochester Today on News-Talk 1340 KROC-AM and 96.9 FM to discuss the nearly perfect storm that greatly strained the region’s electrical power grid on January 24 and 25. Listen to the entire interview by clicking on the link below.

What Caused the January Power Strain

McCollough described the situation created by spiking demand for power due to the Arctic cold blast that gripped much of the nation and a reduction in electricity generation capacity. He explained that extreme cold can impact the reliability of power generation systems and constrain the availability of fuel, particularly natural gas, which has become a mainstay for many utilities as coal-fired power plants are being taken offline.

Lack of Wind Power Generation

On that particular weekend, the high-pressure weather system responsible for covering the Midwest in bitterly cold air also quieted the winds. On the night of January 24 and into the early hours of January 25, McCollough indicated that electrical power generation from wind turbines dropped to nearly zero, which further restricted the supply side of the power equation.

Natural Gas Supplies

According to McCollough, the peak-demand electrical generation units used by Rochester Public Utilities are dual-fuel units, which means they can run on either natural gas or fuel oil. With natural gas supplies constricted by high demand for heating, RPU switched to fuel oil, which was actually less expensive to use than natural gas at the time.

A Tanker Truck Every 2 Hours

The logistics were daunting. McCollough described how RPU staff and its fuel oil suppliers found themselves working around the clock to operate the peak-demand generators and keep them fueled for 50 straight hours to help meet the local and regional need for more power during the cold snap. The operation included bringing tanker trucks to the RPU power plants every two hours to keep them fueled and running.

How Close Rochester Came to Blackouts

The situation resulted in a rare winter event. RPU and utilities throughout the Midwest issued alerts to their customers urging them to voluntarily conserve electricity to prevent the system from being overloaded. According to McCollough, across the regionwide power grid, the cushion between power generation capacity and demand was down to less than 5%, and without a reduction in demand, there was a possibility that rolling blackouts would be needed to prevent a collapse of the electrical power system.

Conservation Helped

Fortunately, the appeal for conservation apparently worked, and by the morning of the 25th there had been an uptick in wind speeds across the Midwest, which brought some of the wind turbines serving the region back online and added generation capacity. That additional power allowed RPU and other utilities to rescind the conservation alert Sunday morning as the crisis eased.