A Crucial Power Source For NorthWestern Energy’s Carbon-Neutral Future

NorthWestern Energy’s Bob Glanzer Generating Station in Huron, South Dakota, is an important part of the organization’s goal of net-zero carbon emissions by 2050, providing an on-demand supplement to wind and solar power. We served as the owner’s engineer for the 58-megawatt, natural gas-fired project, helping oversee and evaluate planning, design and construction.

The original generating station was built in the 1960s and upgraded in the 1990s, but by 2019 a replacement facility was needed. The project includes six reciprocating internal combustion engines, or RICEs, which can reduce nitrogen oxide and carbon monoxide emissions by more than 90% compared to their older counterparts. The engines fire up in eight minutes and are intended to supply reliable power when called upon to respond due to market conditions.

After the engines were delivered in early 2020, our team helped the client navigate the project through the pandemic, including:

• Identifying suppliers for hard-to-source materials
• Coordinating communications between the contractor and the RICE supplier’s field staff
• Monitoring progress
• Supporting site commissioning with difficult programming tasks

The Bob Glanzer Generating Station was completed in May 2022. It’s one of several projects we’ve completed for NorthWestern Energy, including the Jackrabbit to Big Sky Transmission Line in Montana.

Rising to a Carbon Emissions Solution

The U.S. Environmental Protection Agency requires all energy generating stations to adhere to emissions levels within their site boundaries — a challenge for the Bob Glanzer Generating Station project because of its relatively small plot of land.

One option was to make the emissions stacks taller, helping spread dispersion, but the sudden high cost of those materials made this less desirable. Instead, our team found a solution to raise the entire structure by 15 feet using structural steel columns, an economical and easier-to-source material. The result was cost effective and complied with federal regulations.

Providing Cybersecurity and Programming Services

During the project’s commissioning phase, our systems protection and planning team helped program the Real-Time Automation Controller, or RTAC, which provides remote communication with the engine control system and a layer of cybersecurity for crucial generator applications. We were the only project partner with the necessary programming skills to get the various pieces communicating correctly. Upon project completion, our engineers provided RTAC training for NorthWestern's team, preparing them to operate the system going forward. 

Additionally, our oil and gas team also stepped in to solve a programming issue for maintaining a steady gas supply to the site. The main regulating valves reduced supply pressure to an appropriate level for the engines, but supply valves at each engine were searching, resulting in pressure variations that impacted engine operation. We understood how the valves reacted with each other and adjusted the control variables to improve stability and response time.