Four automation tips to better manage the power grid

Advanced automation helps power systems meet the ever-increasing complexity of a changing power industry

By James Nyenhuis April 3, 2024
Courtesy: Emerson

 

Learning Objectives

  • Understand the current challenges faced by modern power generation facilities, both commercial plants and those integrated within industrial manufacturing facilities.
  • Gain insight into the need for modernizing power system operations.
  • Acquire knowledge about the benefits of implementing advanced automation and simulation in power facilities.

Automation insights

  • Today’s power generation facilities face complex challenges due to external pressures, requiring a strategic approach to modern automation software.
  • Adapting to the changing landscape of power system operations is crucial for efficiency and competitiveness, with advanced automation and simulation offering predictive strategies that enhance safety and efficiency, without requiring a complete infrastructure overhaul.

Many of today’s power generation facilities are at an inflection point. Whether it is a commercial generation plant supplying power across half a state or one within the fence of an industrial manufacturing facility, external forces are exerting pressures that complicate operations.

But while the complications of modern power operations may seem insurmountable, few truly are. A combination of a clear understanding of the challenges of modern power generation management and the strategic implementation of modern automation software can help any organization make the most of what they already have for more efficient and effective operation.

Mind the workforce gap

First and foremost, power facilities are seeing a massive shift in the personnel they employ. Operations teams can no longer rely on the expertise of longtime employees who have worked at the facility since the concrete for the foundation was poured. Those personnel are now retiring in droves and plants are seeing the practical ramifications of their departure. Decades of institutional knowledge disappear with each retirement. Simultaneously, complex operations are being handed over to newer personnel who have limited experience with aging assets and decades-old technologies.

Properly training new staff typically takes two to five years, but today’s plant personnel are commonly staying for only two to three. Often, as soon as a new person knows where all the equipment is and has a handle on the quirks of taking the plant through intricate operations such as startup and shutdown, they move on and that knowledge is lost once again.

Moreover, even if an organization can retain personnel, they are getting harder to find. Plants need modern technology to attract the most talented personnel of the new digital-born generation, as they expect to work with advanced systems that provide decision support and mobile access.

New demands for modern operation and automation

In tandem with the complexities of a worker shortage, power generation facilities are faced with mature assets needing to operate in ways that do not align with their original operating specifications. When many of today’s plants were designed and commissioned, they were engineered to support a profile of running turbines at full output for as long as possible to maximize their efficiency of power production. The rise of the wholesale power market, coupled with a global push toward more renewable energy generation, has changed this dynamic (see Figure 1).

Figure 1: North American combined cycle gas turbine fleet cycling metrics show an increase in conventional plant starts and stops associated with growing renewable energy penetration and evolving coal unit retirements.

Figure 1: North American combined cycle gas turbine fleet cycling metrics show an increase in conventional plant starts and stops associated with growing renewable energy penetration and evolving coal unit retirements. Courtesy: Emerson

Modern power generation systems connected to the grid are changing how much and when power is available. Renewable energy sources like solar and wind are changing the game with difficult-to-predict power fluctuations based on changing weather patterns.

To meet demand, thermal and other power plants must ramp their output up and down in response to the variability, causing them to operate away from their most efficient operating point, typically at or close to full output. This results in more complex operations for plant personnel to balance the cost of generating power with varying output and price conditions. If those operations are not performed properly, efficiency is reduced and more wear and tear is encountered on the assets, shortening their life span.

Automation software is the solution

Twenty years ago, plant startups and shutdowns were handled by a deep bench of expert personnel, not only because such operations were more uncommon and required extensive expertise, but also because the control systems did not have the computational horsepower to fully automate coordinated plant process operations. There was not enough memory in the real-time controllers to store the historical data and complex algorithms necessary for advanced process control and automation.

Some organizations ran advanced automation on secondary workstations, but those setups typically required complicated custom engineering. Such solutions were fragile and hard to support, so they were often only suitable for the most confident and well-resourced operations teams.

In contrast, modern advanced control software is designed to simplify this connectivity, empowering teams to leverage the best automation technologies with the control systems they already have in place. Teams might employ Emerson’s Boundless Automation vision of seamlessly integrated data mobility to break away from the complex, custom engineering of the past.

The best advanced control solutions available seamlessly layer sequential automation directly on top of a plant’s existing control architecture, providing teams with the tools they need to easily build institutional knowledge directly into their control systems (see Figure 2).

Figure 2: When embedded into the plant control system, advanced process control reduces variability todeliver better dynamic performance closer to operating limit.

Figure 2: When embedded into the plant control system, advanced process control reduces variability to deliver better dynamic performance closer to operating limit. Courtesy: Emerson

Not only does this built-in knowledge help operators make better decisions as they guide the plant through changing operational states, it also helps ensure that the plant’s best practices are applied every time, through every stage of a workflow, regardless of who is working in the control room. Operations teams are also linking these advanced control solutions with simulation software to build digital twin replicas of their power operations to test new operating strategies and improve training across the workforce for faster upskilling.

These software solutions are easier to implement than ever before because they are making it possible to seamlessly move information from field to edge to cloud to unlock new advanced control technologies and because successful organizations are implementing them using four proven strategies for improved success.

Strategy one: Current state analysis

A team implementing modern advanced control strategies cannot be successful without a good grasp of its starting point. Typically, this starts with an evaluation of two key elements: operator loading and alarm management. Teams should explore and document how many times an operator needs to interact with the control system on an hourly basis and then compare that number against widely recognized standards for best-practice operation.

In addition, the team needs to look at the alarms designed to provide operator awareness. When considering alarm management, teams should evaluate not only the number of alarms coming in, but also the quality of those alarms. Operators can only process so much information. If the control system is constantly overwhelming them with alarm floods, operations will be far less safe and effective.

Fortunately, nearly every control system records alarms and user interactions and then stores that historical data for later access. An experienced automation partner can help the team filter and process that data for clarity into the effectiveness of operator interactions with the control system to build a critical baseline for current operational efficiency.

For example, a large North American power producer recently wanted to centralize operations across its network and recognized it would need to streamline, standardize and automate many parts of its operating procedure. In researching best practices, the team discovered industry studies showing the ideal target to optimize operational decision-making is 6-10 control system interactions per hour.

The power producer’s team partnered with its automation provider to collect historical data and discovered that between changing setpoints and moving operations from automated to manual, their personnel were interacting with the system significantly more — at 5-10 times the ideal limits. Knowing the baseline helped the team develop goals for their advanced automation project because they knew if they could bring operators into the 6 to 10 interactions per hour range, they would be more successful at managing multiple facilities.

Strategy two: Shore up the automation foundation

Trying to implement advanced control on top of an unstable automation foundation is a recipe for frustration. After a team has identified its baseline and targeted goals, the next step is to find the parts of the process where the team can true up the base level control strategies.

The need to revisit basic automation strategies is not uncommon. Many plants find that control strategies implemented decades ago were not engineered to today’s best practices or were not as robust as they need to be for operation in the modern industrial manufacturing marketplace. But even optimally engineered plants change over time as their range of supported operations increases.

Meeting new goals with aging infrastructure will nearly always require some reconfiguration. Leveraging specific advanced process control techniques for drum level, emissions, steam temperature, unit response and other systems helps optimize control of plants with a more dynamic operating profile.

Additionally, implementing adaptive, advanced software that continuously assesses process performance, identifies degrading conditions and adapts to ever-changing conditions helps increase production and ensures optimal efficiency over a wide range of operating states.

Strategy three: Implement sequential automation

Once the plant has its core automation systems running as expected and in line with best practices to the greatest extent possible, the team can consider adding advanced automation strategies to lock in best practice controls and help operators of any skill level more efficiently and effectively drive their power generation processes. Step-by-step automated operator guidance through normal operations — and process aberrations — helps to ensure procedures are performed the same way consistently, regardless of which shift is on duty.

The best software solutions for sequential automation integrate seamlessly with the control system, so automated operations feel like a normal extension of operational procedures. And even more importantly, they integrate seamlessly with the best modern simulation tools to provide operators with testing and training platforms that look and feel just like the actual plant controls in the control room. Empowered with decision support at every stage of operations and a safe sandbox in which to learn and improve strategies for uncommon operations, operators are elevated to higher-level process managers, more focused on driving continued efficiency and equipment health than on firefighting.

The aforementioned North American power plant looking to improve operations identified a common issue in its operations that, if remedied, could dramatically improve efficiency, safety and uptime. Due to fluctuations on the grid, both from an increase in renewables and from constantly shifting electrical demand, the team had units starting and stopping almost daily to manage the change in load from daytime to nighttime and from on- to off-peak.

When the team needed to reduce load, they would have to stop their gas turbines — large, highly refined pieces of equipment. After the turbine cooled down, the team would have to perform a very complex startup procedure to safely heat the metal up again and get it started (see Figure 3).

Figure 3: Solar energy penetration is changing traditional operating profiles, calling for more active response to compensate for variable renewable generation during the daytime, along with increasing plant demands at night when solar is not producing and winds typically decrease.

Figure 3: Solar energy penetration is changing traditional operating profiles, calling for more active response to compensate for variable renewable generation during the daytime, along with increasing plant demands at night when solar is not producing and winds typically decrease. Courtesy: Emerson

Not only did the startup and shutdown processes introduce complexity and risk into operations, they also added extra wear and tear on equipment that was designed for continuous operation. By layering automated sequencing technology over their existing automation, the plants were much better equipped to support more cyclical operations. The team gathered data on best practices for the startup and shutdown process and then built those strategies into automated workflows for turbine operation.

But even more importantly, they were able to seamlessly connect operational data with real-time digital twin simulation to help identify patterns of operation from a wide range of variables. Using these predictive patterns, the team layered in new automation strategies to more gradually adjust load to meet operational requirements, reducing the number of times operators needed to stop and start equipment.

Strategy four: Demonstrate success

Few, if any organizations achieve operational excellence by implementing a single change and then stopping their improvement program. Once a team sees success with their new automation systems, they will likely want to implement more enhancement. To sustain continuous improvements, it is critical to determine the right metrics to track performance against an original baseline, confirming the value created for the plant with each change. Utilities can get additional support in determining the best metrics to meet their plants’ objectives by working with a trusted partner with decades of global industry and operational experience.

As teams gather metrics and identify success in their key performance indicators, they should not only share those achievements with management — but also with the maintenance, operations and engineering teams to generate buy-in across the organization — as operational excellence requires support from the entire enterprise. Demonstrating success is the fastest way to leverage wins into future projects and more effective personnel (see Figure 4).

Figure 4: Integrating operating procedures into a control system using advanced strategies drives operational consistency, resulting in cost savings and a potential ROI of 1-2 years.

Figure 4: Integrating operating procedures into a control system using advanced strategies drives operational consistency, resulting in cost savings and a potential ROI of 1-2 years. Courtesy: Emerson

Automation generates a better foundation

Modern power system operations — whether in a power utility or a small plant supporting other industrial manufacturing operations — have changed dramatically, even in just the past 5-10 years. Continuing to run these operations using strategies developed decades ago makes it difficult, if not impossible, to compete in a modern, global economy. Fortunately, most teams can improve operations without a complete rip-and-replace overhaul of their infrastructure.

Modernizing a power facility’s operations with advanced automation and simulation unlocks predictive strategies that keep maintenance and operations teams safer, while increasing their efficiency. And because the key steps to implementing those technologies are process improvements every team should already be considering, there is no reason to avoid starting the journey toward advanced automation.


Author Bio: James Nyenhuis is manager of performance consulting for the power industry at Emerson.