Efficient operations and maintenance (O&M) and asset management practices are imperative to maintaining power plants in a good state ensuring the quality of assets over lifetime and enhancing operational performance. A systematic O&M of power plants is critical to ensure that plants perform to the best of their designed parameters, delivering maximum uptime and generation. The building blocks of a good O&M service are regular monitoring and analysis, preventive maintenance practices and rapid trouble shooting. A planned schedule of comprehensive preventive maintenance practices can reduce the dual loss of unplanned downtime and repair costs of the thermal power plant (TPP). Moreover, digitalisation of O&M and asset management practices is taking place rapidly with the introduction of advanced communication networks, internet of things (IoT), cloud-based platforms and advanced analytics among other things. Such digital systems can perform multiple functions in O&M space such as improvement of TPP efficiency, reduction of operational expenses and mitigation of unplanned outages, leading to enhanced equipment life.
Transition from reactive to predictive maintenance
The advancements in the digital O&M space are driving the transition from reactive to predictive maintenance. The focus is now on predicting likely anomalies and addressing the causes beforehand, instead of diagnosing and rectifying faults after they have occurred. Predictive maintenance can be defined as an O&M practice that uses data analysis techniques for the identification of possible defects in the system components, so as to prevent any downtime.
Most power project operators use supervisory control and data acquisition (SCADA) for remote monitoring and management, which can be used for effective O&M. However, with SCADA, only a limited amount of sensor data can be monitored by operators, while most failures frequently originate from previous unknown and undetected anomalies. Thus, it often becomes difficult to find the actual raise of the issue. Moreover, basic SCADA systems can only sound an alarm after a certain programmed value level is crossed and by then, it is too late to take any corrective action.
Predictive maintenance ultimately helps in reducing the long-term operating costs of a project as it helps prevent system faults and product damages. Moreover, this practice enables proper planning for ordering spares and scheduling essential maintenance work. If predictive maintenance is carried out properly, O&M teams will have to make less frequent visits to the project site as the manpower requirement will be reduced for fault detection and repair activities, since minor repair work or issues can be handled remotely.
Predictive analytics becomes even more critical when the world is grappling with the impact of a global pandemic. During second and third waves of the Covid-19 infection, many countries imposed lockdown again. In this scenario, predictive O&M helped in acquiring data, analysing it and taking action accordingly, especially since many O&M engineers were confined to homes and not be able to visit project sites. Thus, predictive O&M is more suitable for these plants as compared to traditional O&M, which requires dedicated manpower at project sites.
New and emerging technologies
The application of digital tools such as advanced software, sensors, artificial intelligence and machine learning assists in efficient remote monitoring and analysis for identifying any likely faults before they occur. The real data parameters will also help to carry out the day-to-day O&M by predicting energy generation, improving reliability and defining maintenance strategy. Many operators have now started moving towards intelligent predictive maintenance based on advanced sensors and IoT. Defects can be recognised and rectified before any large damage occurs, which can lead to significant cost overruns, thus minimising sudden breakdowns.
To reduce human risk in the O&M process, drones can be used for inspection, while robotic technology can be utilised for cleaning and maintenance. In most situations, drones can give better quality data than manual inspections. These drones are often equipped with a digital camera, a thermographic camera, or a combination of both. With thermographic inspection, one can get more accurate data regarding the temperature in large areas, hidden defects, corrosion and other abnormalities. Moreover, digitalisation can help create a dynamic visual representation of a power asset. This virtual representation, called the digital twin, can be used to predict the performance of a physical asset in certain conditions.
In order to effectively manage power plant O&M, operators often enter into contracts with original equipment manufacturers (OEMs), engineering, procurement and construction (EPC) companies, maintenance companies and consultants to handle any major plant outages. At the same time, in-house staff are generally responsible for routine and minor outage maintenance work. However, in the current competitive environment, operators are looking at outsourcing more of their maintenance requirements.
Besides having technical skills to carry out the maintenance work, OEMs are able to provide materials management. This not only allows a power plant to reduce inventory costs, but can also reduce equipment downtime. In addition, depending upon risks, an outsourced contract can include performance-based guarantees tied to the duration of planned outages, equipment availability and heat rate of the plant.
Outsourcing O&M provides multiple advantages to the captive power plant operator. It allows the operator to focus on the core business and reap the benefit of low-cost power, guarantees system availability and response time, facilitates real-time monitoring and analysis of plant performance and provides access to the knowledge base of O&M contractor developed by serving multiple plants. In case of an unplanned breakdown, it is essential to respond quickly to resolve the failure and restore regular operation of the plant. The speed of response depends on the availability and strength of a dedicated service team as well as an established network of associates who can reach the customer on demand. Thus, outsourcing O&M can promptly address any plant breakdown with a dedicated and experienced O&M team.
Going forward, increasing digitalisation and automated remote monitoring are expected to revolutionise the way O&M is carried out. An O&M service provider with EPC background and a strong engineering expertise to tackle any technical issues and the procurement strength to engage with various OEMs for spares and warranty issues would ensure that O&M requirements are addressed right at the project conceptualisation stage for easy maintenance. Outsourcing power plant equipment maintenance to third parties is becoming more prevalent as it allows operators to focus on asset management and core business areas. Apart from this, with rapid technology advancements in automation and digitalisation and the resultant improvement in O&M efficiency and cost, it is expected that the majority of O&M activities will be carried out through digitally enabled techniques in the near future in India as well as the rest of the world. The Covid-19 pandemic has certainly highlighted urgency to digitalise O&M. With lockdown measures imposed, and shortage of spares and manpower experienced, developers and operators have realised the merit in transitioning to advanced digital O&M practices and predictive maintenance techniques.