The growth of intermittent renewable energy is forcing combined cycle power plants to increase flexibility to stay competitive and ensure grid reliability. The pressure on gas plants to operate in a flexible mode is accelerating ramp rates and extending minimum load operation. Load cycling, frequent startups, and shutdowns introduce unforeseen stresses that accelerate the wear and tear of the plant’s hardware and reduce performance & asset life expectancy.
Pressure from Stakeholders
The US is making a turn on Energy Transition. President Biden signed again the Paris Agreement and can be foreseen changes in the way electricity will be produced.
European countries and power producers have already crossed this path, and this experience is a unique opportunity to benchmark from Europe and adapt your plants and ways of operating to an unstoppable transformation of the industry.
Power producers suffer or will suffer soon a lot of pressure from their stakeholders to support energy transition. These pressures bring consequently different operation modes, different dispatch, and different P&L for thermal power plants.
And that pressure is not decreasing in the following years…
The need for flexible resources
While some energy systems are changing toward reducing emissions, the world is off track from what is needed to achieve the Paris Agreement goal of limiting global average temperature increase.
As BloombergNEF published in its report “Flexibility Solutions for High-Renewable Energy Systems”:
“The question is no longer whether clean technologies are going to be the cornerstone of the future energy system, but rather which flexibility options will back them, and how to address the operational and market challenges that will arise.”
The need for flexible assets to complete or back up renewable sources brings operational and business changes to thermal power plants. Challenges such as oversupply and curtailment of renewable energy sources are already being addressed by System Operators.
The Problem
Without these new market requirements, thermal power plants were operating in the stable zone. But to work in a flexible mode, the plant is forced to move to new optimal operation points, closer to constraints where dynamics are more challenging.
The problem is that most Thermal Power Plants is that they were designed as baseload units, so working in a flexible mode is against their nature. Additionally, the increase in the frequency and magnitude of load changes reduces the lifetime of the power plant equipment.
Many electricity generators, that are frustrated with their poor performance in a competitive marketplace, may be surprised to learn that their plants are mechanically capable of greater operating flexibility, and to find that their plant control systems are the limiting factor.
Existing technologies can improve the status, but they do not provide all the required flexibility. The technical possibilities to increase the flexibility of existing thermal power plants can be divided into two categories: hardware retrofits which are very expensive and, and control system optimization which does not fix this problem.
Existing Control Systems and PID controllers
Power plants have several advanced process control systems available in the market based on various control methodologies, such as fuzzy logic, neural networks, or model predictive control. Each applies their control actions through well-known PID controllers at the DCS level, which interfaces with the plant’s actuators and sensors.
This PID controller has some physical constraints that limit the performance of the controlled process, particularly in changing environments such as flexible operation. These controllers are mono-variable and configured with fixed-parameters for a limited number of known situations. But the dynamic scenarios of the plant are infinite, and some combinations of variables are unexpected during the plant commissioning phase.
Our Self-tuning AI control solution
ADEX solution is a patented technology for industrial process control in the form of a Self-tuning Artificial Intelligence Platform. This Platform is an add-on to the existing control system, does not require any additional equipment or instrumentation nor any big data or machine learning as it tunes in real-time to the changing dynamics of any process.
The key difference is our patented Controller which substitutes the old PID. ADEX Controller is multivariable and self-tunes in real-time to an infinite number of scenarios. And so, it predicts the dynamics of the controlled process, anticipated the changes, and avoids error.
If your plant is in a market demanding flexibility, we encourage you to listen to the webinar and contact our experts for a Room for Improvement Analysis.
Webinar recording
In this webinar, you will listen to first-hand real cases of ADEX Self-tuning AI on combined cycle power plants from ADEX’s CEO, Jose Martínez.
He is joined by Enrico Falesiedi, Head of Gas Operations of Enel, the world’s second-largest utility by market cap and leader in 2020 Dow Jones Sustainability World Index, who will share his views on the gas plants challenges and how ADEX‘s solution helped improve the plant’s thermal efficiency, flexibility, and emissions footprint.