Optimizing Steam Power Efficiency with Predictive Analytics

The Calcutta Electric Supply Company (CESC), headquartered in Kolkata, India, is one of the oldest private sector electricity generation and distribution companies in India. It was founded in 1899 as the Calcutta Electric Supply Corporation, with the primary aim of generating and distributing electricity to the city of Kolkata (formerly known as Calcutta). Today, it is a flagship company of the RP-Sanjiv Goenka Group, one of India's leading business conglomerates. With a strong presence in the eastern region of India, CESC serves millions of consumers across Kolkata and its surrounding areas, including parts of West Bengal and parts of Jharkhand.

CESC has been a key contributor to the energy landscape of Eastern India for over a century, playing a vital role in powering the economic growth and development of the region. The company operates a diverse portfolio of power generation assets of thermal power plants. These facilities collectively generate a substantial amount of electricity to meet the growing energy demands of the region. And, like many energy producers across the globe, they are working hard to provide reliable, affordable and sustainable energy—while also navigating the energy transition. In total, CESC produces more than 2 gigawatts of power to help keep India running.

CESC is a 567 sq. km distribution licensee that operates across a region that provides power to 3.2 million customers (domestic / industrial / commercial). To do so, CESC and its sister concerns are running five thermal power plants for a combined 2140 MW of capacity. Due to the major requirements for their customers and their desire to exceed performance, CESC noticed areas of operation that required attention.

With such a large footprint, CESC discovered that to reduce Operations & Maintenance (O&M) spend and downtime, a single system must be deployed to create visibility and drive standard work for the organization. Historically, CESC has performed maintenance activities plant-by-plant, with engineers at each site being responsible for the program. Although effective, leaders at CESC saw the need to develop standards and share information across sites to deliver more outcomes.

Since CESC operates many critical assets to produce their 2+ gigawatts of power, another requirement emerged. This requirement was the ability to gain granular insights about not only the asset itself, but the surrounding components and processes. To do this, CESC determined that advanced pattern recognition was required in order to generate proactive maintenance recommendations with accuracy

CESC decided to leverage GE Vernova’s Software businesses Asset Performance Management (APM) as their Remote Monitoring System of choice. From GE Vernova’s holistic suite of APM offerings, it was determined that an on-premises deployment of APM Reliability, powered by SmartSignal, met and exceeded their criteria to solve the aforementioned challenges. At the beginning of CESC’s journey in 2018, they leveraged GE Vernova’s Industrial Managed Services (IMS) for six months to help create cases and recommendations—while simultaneously training CESC on how to adopt and use the software on their own. In this engagement, CESC was able to show value to the organization, quantify results using GE Vernova’s IMS framework and ultimately scale the solution.

The implementation of GE Vernova’s composable SmartSignal predictive analytics allowed CESC to leverage their engineering domain expertise alongside GE models to prevent unplanned downtime. Within APM Reliability, users gain the ability to deploy analytics on the assets and components that matter the most to their operation. Leveraging sensor data, APM Reliability can integrate with Historian and other systems to generate a 360-degree view of selected assets.

Once the Digital Twin is built and connected to the identified assets, CESC was able to leverage the application to detect small deviations from normal running patterns. With these regression models, CESC can compare one asset to normal operating levels and take proactive actions during low demand periods to ensure continued optimal performance. With APM Reliability, using advanced pattern recognition allows CESC to react faster and reduce the time spent by employees to perform maintenance tasks. CESC prioritized this work by creating ‘normal’ and ‘repeat’ alerts that helped to understand the urgency behind the data. In doing so, CESC has been able to generate catches such as:

Case-1: Air Pre-Heater-A Customer Observation

• In one of the CESC Unit APH-A Guide Bearing Housing temperature went from 46 deg C to 55 deg C at 16:33 Hrs. on 20th December,2023.
• Rapid Action Notification sent by the Central Monitoring Team at 16:39 Hrs through email and SMS.
• System returns to normal at 17:54 Hrs on the same day after actions taken by the site team. It was found that Cooling water supply valves inadvertently remained shut after annual overhauling that was normalized by the site team after getting notification from SmartSignal diagnostic advisory thus critical asset damage could be avoided.

Case-2: Primary Air Fan-B Customer Observation

• SmartSignal notified that in one of the CESC Unit PA fan B motor current was running at 62 A as compared to its earlier running values of 44 A. Also fan RPM increased to 1424 rpm compared to its earlier running values of 1224 rpm.
• Case was generated on 09 September 2022 at 9:36 Hrs by the Central Monitoring team and sent the case by email and SMS to the site team.
• Immediate action was being taken by the site team. Site replied that PA Fan 1B, suction damper positioner assembly detached from foundation base - later attended. PA Header pressure was increased by PA Fan 1A for support, resulting in increasing fan current and RPM thus equipment reliability was ensured.

Case-3: HP Heaters 6 & 7 Terminal Temperature Difference (TTD) Customer Observation

• SmartSignal notified that in one of the CESC Unit HPH 6 & 7 TTD, had increased up to +4.8 deg C and +7.9 deg C, while design value is 0 deg C. It was directly affecting Station Heat Rate.
• Case was generated on 25th September 2021, at 10:48 Hrs by the Central Monitoring team and sent the case by email and SMS to the site team.
• The action was taken during an annual survey. Site team replied that during Annual Overhauling, partition bolts of HPH 6 & 7 were found to be in a missing condition causing shortcircuiting of extracted steam and feed water. Same was rectified during Annual Overhauling.

Now TTD for HPH 6 & 7 are -1.6 Deg C and +2.6 Deg C respectively - thus process efficiency could be improved.

With implementation of APM Reliability, CESC created a Central Monitoring Team that is responsible for carrying out monitoring asset health along with the site teams. In the Central Team, assets are monitored in near-real-time, and alerts are contextualized for CESC to host a weekly meeting with each site to discuss the Root Cause Analysis (RCA) and corrective action or preventative action (CA/PA) to be taken. CESC is also doing innovative work to leverage SmartSignal alerts in a dashboard, perform queries based on trends, and generate prescriptive recommendations across sites based on historical data.

• Enhancement of asset reliability
• Reduced downtime
• Scaled to more assets
• Broad adoption across site
• Standard work from centralized Monitoring & Diagnostic team

*Information provided and validated by CESC. The Information contained in this document is indicative. No representation or warranty is given or should be relied on. Information provided is subject to change without notice.