Lifecycle effectiveness is the overall measure of operational success. It incorporates several goals, such as lowest lifecycle cost, highest possible efficiency and the ability to meet environmental targets. Broadly speaking, the concept comprises two key categories of measurement: the performance of the equipment, the personnel operating it, and the factors that make up the equipment’s operational availability.
Operational availability is the percentage of time that a system performs, or is ready to perform, satisfactorily in an operating environment (expressed, for example, as uptime plus downtime). Uptime and downtime are affected by three factors: reliability, maintainability and supportability. There are various ways of looking at availability, e.g. the availability rate based on MWh/year.
Power system analysis
Plant measurement systems should preferably employ the newest and most efficient technology available in order to keep up with today’s requirements and tomorrow’s challenges in monitoring and data collection. Environmental aspects are another important consideration, especially the need to obtain accurate information on vital energy production parameters to keep the plant within environmental limits.
Denmark’s gas-fired Frederikssund Kraftvarmevaerk plant has remote monitoring in place
To achieve the maximum level of performance, older installations need to consider automation modernization packages to upgrade to the latest technical standards. In many cases this means adopting digital in place of analogue systems.
As a large engine plant supplier, the Finnish company Wärtsilä maintains an internal power plant Operations and Maintenance (O&M) group which works with all sizes of power plants. This group not only incorporates the know-how of the power plant designer and supplier, but also the experience of professional operators and the maintenance knowledge of the global Wärtsilä Service network.
In cases where power plant operation is not the owner’s core business, customers increasingly see the logic of outsourcing the operation and maintenance of the plant. This allows them to concentrate on their own business leaving O&M to specialists in their field and has a positive impact on the power plant’s lifecycle effectiveness.
The service projects group specializes in bringing older plants up to today’s technical standards, covering everything from initial audit to electrical, mechanical and automation modernization.
Remote connections with data acquisition systems can be also installed. Companies such as Wärtsilä now offer specialized systems covering data acquisition, fault analysis, planned maintenance and technical information.
The WOIS Connect information system controls vital information flow and alerts standby maintenance personnel to any major problems
Monitoring a power plant from a remote location is becoming increasingly popular and can be a key factor when customers are choosing their engine supplier. Complete updating and modernization can be supplied either for part of the power plant or for the whole facility, including the mechanical, electrical and automation systems.
Remote monitoring offers fast and easy on-line support while trouble shooting system faults resulting in less downtime. It is possible through this system to discuss operational parameters (trends) with staff making it possible to avoid problems before they occur and to optimise engine performance.
The power plant receives support at all times because experts are able to monitor plant performance without incurring wasted time visiting them. Following major overhauls the engines can be closely observed to ensure optimum performance is being achieved. In addition, small updates in the supervision system can be made remotely.
Out of the millions of industries operating today, the power plant is just another one that has become dependent on the advances of technology. The flow of data involved within the daily operation and maintenance of a plant is vast and has become evident that in its current congested form, the average human cannot utilise the given information to its potential.
Power plants, large or small, are a problem when it comes to maintenance and supervision. Not only is there a number of high-tech systems requiring continuous supervision and control, but there are also increasingly high requirements on the optimal operation of these systems. All this, plus the escalating number of measurements and tools for evaluation are leading to an information overload!
Wärtsilä has been monitoring these changes within the power plant and pro-actively developed a new information environment Wärtsilä Operator’s Workplace. The company has recognised that it is the primary control system which needs to be designed properly in order to prevent sub-optimal operation, inefficient maintenance and in a worst case scenario, a hazardous situation.
In order to offer personnel better ways of taking fast and correct decisions,Wärtsilä has created two separate tools for operation and maintenance. They consist of the operation critical process visualisation tool WOIS (Wärtsilä Operator’s Interface System) and the operation and maintenance data tool WISE (Wärtsilä Information System Environment).
Traditionally, the most important tool for process supervision and operation has been the operator’s interface system, providing process visualisation, data trending, alarm handling and event logging. Presentation is the key to this system enabling operators to be clearly alerted to process problems and take fast, appropriate action.
The Skagen remotely monitored plant in Denmark is installed with threeWärtsilä’s V28 SG engines
The WOIS system has been graphically designed selecting colours for clarity and ergonomics. The system has been constructed using input based on the experience and expertise of engine developers, plant specialists, service personnel and customers ensuring important details are not overlooked.
The energy market of today has moved from traditional, big centralized solutions towards a more decentralized energy production, often resulting in unmanned plant operations. The WOIS Connect service alerts standby maintenance personnel to any major problems at the plant.
From a portable WOIS workstation, employees can connect with the power plant, investigate the situation and take the necessary action. In turn,Wärtsilä can also make use of the service, which helps them maintain parts of the control systems and also remotely assist customers with fault tracing and problem solving. When problems can be diagnosed and corrected in minutes instead of days, it becomes apparent how much of a substantial saving can be made.
While WOIS is useful for fast decisions and deployment of maintenance on plant problems, it is not sufficient for efficient operation and maintenance management. This is where the second major part of theWärtsilä Operator’s Workplace comes in with the WISE information environment.
The management of a power plant demands a variety of tools for a number of aspects such as analysis, reporting and general maintenance logging. The systems and tools used for these processes are heterogeneous and therefore personnel trying to use these different forms of data encounter hindrances in the efficient operation of a plant.
The WISE environment is a platform that contains the minimum number of tools considered for the efficient operation of a power plant. They include:
- Technical information like maximum, minimum and average values of process measurements, presented on a daily, monthly and yearly basis. This data can be used to evaluate the process condition, and is used for technical follow-up.
- Production and consumption, like electricity and heat production, fuel and lube oil consumption etc, giving indication on e.g. plant efficiency, and used for commercial follow-up.
- Information on the availability and reliability of the plant. The information can also be sent toWärtsilä that will provide the plant owner with a benchmarking report, helping the plant owner to better keep track of his own performance.
- An electronic logbook where all starts and stops are automatically entered together with the major stop reason. In addition to this information, the O&M personnel can enter their own comment on the events. The personnel can also add other information to the system as general information.
- Feedback toWärtsilä can be entered into the system, and will be used byWärtsilä for further product development.
The WISE system is linked to the WOIS, meaning that when mutually important data on the plant and its processes are updated, it will register on both systems. This co-ordinated operation allows maintenance personnel to eliminate the usual sifting through of irrelevant information and instead use their time more efficiently to solve the problem in question.
In addition to the standard tools in the WISE environment, also available are a selection of optional services and tools which include:
- Process video supervision
- The MAMA maintenance management system
- Electronic technical manuals
- Other support tools.
The WISE environment thereby integrates all various information and tools in one environment, where the O&M personnel can simply access information and plan the operation.
Power plant operators have become increasingly interested in optimal maintenance. Replacing parts on a fixed maintenance schedule can be wasteful if they have only reached a fraction of their efficient lifetime. In some cases the parts condition status can be better than expected e.g. due to fuel, lube oil quality and operational history.
In order to facilitate this idea in a more cost-effective and safe way,Wärtsilä has introduced a CBM (Condition Based Maintenance) service where the plant owner will receive expert advice on how to schedule an optimal maintenance programme.
Wise Connect enables substantial plant operational data, required for the CBM service, to be transferred automatically from the WISE system at the plant to a central data analysing facility atWärtsilä. It is here that experts will analyse the data and determine necessary and optimal maintenance of the plant to keep the targets on efficiency and availability.
Remote monitoring is becoming more popular in Denmark as plant operators come to recognise the benefits it brings, in fact all newWärtsilä plants are being remotely monitored. The trend is that more and more projects are going to be handled remotely.
There are three different monitoring systems currently being used in Denmark. There are two Monico Monitor systems that both use analogue modems, one system is for Macintosh computers and the other is for PCs. The third system, called WOIS uses DDE share via ISDN routers.
In the Monico Monitor system for Mac or PC a computer and software is installed at each plant. This computer collects data from PLCs and WECS (Wärtsilä Engine Control System) placed on each engine via data bus (modbus or profibus fms). The data is shown on screen using the Monico software.
At the Denmark head office in Esbjerg and Hirtshals, similar computers and software are installed. There is a button for each plant placed on a country map. When this button is pressed, a standard modem calls at each plant via a normal analogue phone line.
The third system WOIS also features a computer installed at the plant. This computer collects data from PLCs and WECS (Wärtsilä Engine Control System) placed on each engine via DDE and profibus fms. Data is displayed on screen. In the head office in Esbjerg and Hirtshals similar computers are installed. They have the same WOIS software installed as the computers on the site.
Each plant location is identified on a country map by a button. When this button is pressed, an ISDN router calls the plant via an ISDN line, a TCP/IP connection is then made. The same application on the site is opened, but instead of receiving data from a local profibus / DDE server the data is received from the remote, and the ISDN router is much faster to connect. An advantage of WOIS is it that updates to the application can be done remotely.
The Frederikssund Kraftvarmeværk power plant in Denmark is a good example of remote monitoring in action. The plant is owned by the electricity supply company NESA and is based on twoWärtsilä 18V34SG 5.5 MW, it was put into operation in December 1996
This cogeneration plant is natural gas-fired and produces electricity to the common grid and district heating for the city of Frederikssund. The plant produces 11 MWe and 13.8 MWth.
Remote monitoring of the plant was built into the basic contract and was fitted from new. The monitoring system was set up with the plant’s own In-Touch PC and links directly toWärtsilä Denmark via an ISDN line, from where the plant is monitored.
Jan Dommerby, Frederikssund Kraftvarmeverk plant manager claims: “The main advantage of remote monitoring for NESA is the efficient plant operation achieved. The monitoring service engineers are able to evaluate and advise on operational factors and conditions.
“Their recommendations, to the plant’s operational personnel, are key to optimizing engine operations. In situations where technical problems require quick solutions remote monitoring provides effective analysis and practical advice.”