SCADA SYSTEM - TOOL AND PARTNER FOR SUSTAINABLE AGRICULTURE DEVELOPMENT

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1 Buletin USAMV-CN, 64/2007 (1-2) SCADA SYSTEM - TOOL AND PARTNER FOR SUSTAINABLE AGRICULTURE DEVELOPMENT Mircea Adrian Grigoras 1., Agatha Popescu 2, Emilin Merce 1, Felix Arion 1 University of Agriculture Sciences and Veterinary Medicine Cluj, Calea Mănăştur, nr. 3-5, magrigoras@yahoo.com. University of Agriculture Sciences and Veterinary Medicine Bucuresti Key words : SCADA, progressive management, new paradigm Abstract: This article aims to establish a proper management of the SCADA system implementation. A progressive management is described, along with the benefits a SCADA decision support system can offer in the field of sustainable agriculture development. The basic idea is that we need to apply our knowledge to the fundamental redesign of our technologies in order to be able to bridge the current gap between research and economy. INTRODUCTION Pressure from the government, consumer and environmental organizations regarding sustainable agriculture has increased over the last few years. New approaches and new methods have been accepted as standards and are used by others all over the world. Introduced in the early 80's by Lester Brown, founder of the Worldwatch Institute, the concept of sustainability defined a sustainable society as one that is "able to satisfy its needs without diminishing the chances of future generations." [1]. Several years later, the report of the World Commission of Environment and Development, the so called "Brundtland Report", used the same definition to present the notion of sustainable development: "Humankind has the ability to achieve sustainable development - to meet the needs of the present without compromising the ability of future generations to meet their own needs" [2]. These definitions of sustainability are important because they remind us of the responsibility to pass on to the future generations a world with as many opportunities as the one we inherited. However, this definition does not tell us anything about how to build a sustainable society. Most societies aspire to achieve economic development to secure rising standards of living, both for themselves and for future generations. They also seek to protect and enhance their environment, now and for their children. Reconciling these two aspirations is at the heart of sustainable development. The debate is often presented in terms of a conflict between economic activity and the environment, as if it is only possible to pursue one at the expense of the other. But this is mistaken: economic activity and the state of the environment both affect the quality of life. Often economic investment and environmental protection - or improvement - go hand in hand. What matters is that decisions throughout society are taken with proper regard to their environmental impact [3]. There are also many ways in which the right kind of economic activity can protect or enhance the environment. These include energy efficiency measures, better product design and marketing, waste minimisation, environmentally friendly farming practices, better use of land [4], and, last but not least, improved technology and techniques of management, along with the implementation of up to date technologies, such as SCADA systems in the field of agriculture. WHAT IS SCADA? SCADA stands for Supervisory Control and Data Acquisition. As the name indicates, it is not a full control system, but rather focuses on the supervisory level. As such, it is a purely software package that is positioned on top of hardware to which it is interfaced, in general via Programmable Logic Controllers (PLCs), or other commercial hardware modules.

2 Widely used in industry for Supervisory Control and Data Acquisition of industrial processes, SCADA systems are now penetrating other domains as well. Today, SCADA technology offers key systems for various applications in agriculture, environmental control, irrigations, water management, disease control, insect control, and many others. Fig.1 SCADA system. Functional diagram SCADA systems have made substantial progress over the recent years in terms of functionality, scalability, performance and openness such that they are an alternative to in house development even for very demanding and complex control systems. Hardware architecture: one distinguishes two basic layers in a SCADA system: the "client layer" which caters for the man machine interaction and the "data server layer" which handles most of the process data control activities. The data servers communicate with devices in the field through process controllers. Process controllers, e.g. PLC's, are connected to the data servers either directly or via networks or fieldbuses that are proprietary or non-proprietary. Data servers are connected to each other and to client stations via an Ethernet LAN. Software architecture: the products are multi-tasking and are based upon a real-time database (RTDB) located in one or more servers. Servers are responsible for data acquisition and handling (e.g. polling controllers, alarm checking, calculations, logging and archiving) on a set of parameters, typically those they are connected to. In a SCADA system different RTUs (Remote Telemetry Units) and sensors as well as various accessories are available to constantly monitor and transmit important information such as temperature, precipitation, wind speed and direction, leaf wetness, solar radiation, soil moisture, soil temperature or barometric pressure. The wireless technology employed allows for an easy setup of large-scale measurement networks which can handle up to 200 data collection points or more per Base Station. Monitoring the network one can receive site-specific weather and soil data in near real-time. Retrieve Data can be retrieved conveniently at every office and save precious time and money. The state-of-the-art visualization software provided by modern SCADA systems gives exact recommendations when and where to spray or irrigate resulting in optimized yield and quality. Falling producer prices and rising costs of production are increasingly forcing agricultural businesses to optimize production costs. Therefore "precision farming", the selective use of inputs such as water, fertilizers or chemicals, is now indispensable in modern agriculture[5]. The growing environmental awareness of consumers further accelerates this process [6]. SCADA systems provide: site specific weather information, reliable wireless data transfer, almost real-time availability of important data, state-of-the-art consultancy software, proven disease models, optimal treatment recommendations. The growers benefits are: getting important sprays when and where they are really necessary (which may save up to 40% in chemicals spraying, depending on season and conditions), increase yield and quality, saving energy, time and money, improving environmental stewardship, increased profitability.

3 Fig. Inputs and outputs from a SCADA system SCADA systems allow a decision support system that accurately predicts pests and diseases and recommends on the timing of the control. The system can easily be extended with a module for water management or insect control. The decision support system consists of a set of complex models developed with scientific knowledge and by years of experience. Based on local weather data, weather forecast and crop data the model calculates predictions and recommendations for local fields. The implementation of the decision support system advices will result in improvement of yield and reduction of costs for chemicals and water. Each grower has to enter basic crop data like the location of the field, grown variety and soil type into the model. For accurate disease control advices, the farmer has to enter the actual growth situation of the plants, the presence of disease outbreaks and spraying details. All this data is being used for a accurate and field specific advice. All other relevant information is supplied automatically. The weather forecast is provided over a variable number of days period with a selected forecast interval. The expert knowledge in the models is largely derived from scientific literature The decision support system disease forecasting models are developed in close cooperation with experts in crops and diseases. For good decision making, actual weather conditions on the field are important. To obtain this information the decision support system uses the information of local weather stations which are located on farm. All information from this production chain is gathered through the Internet on a specific databank. The system takes care of collection, processing, storage and distribution of all kinds of data as the driving power for the decision support system advisory modules. PROGRESSIVE MANAGEMENT OF SCADA PROJECTS Typically SCADA will be required for some of the following reasons: To reduce power costs. To reduce staffing. To reduce future capital requirements. To improve level of service. To avoid environmental incidents. To comply with regulators requirements. It may not be possible to run the business without SCADA. To obtain a competitive edge To replace an existing aging system All project management methodologies involve breaking a project down into phases, usually with approval gateways at the end of each phase. A further breakdown into tasks is used to produce a work breakdown structure (WBS). Typical Project Management Phases of a Typical SCADA project Identification. Initiation. Definition. Design. Acquisition. Project Closeout.

4 Identification: identify need; prepare preliminary estimate; raw estimate of costs; obtain approval for funds or resources to proceed to the next phase. This phase is normally informal, and does not require a lot of resources. The identification of need may have arisen out of some other activity, such as development of new farm, review of soil and water condition, shift to a sustainable agriculture. This phase is a crucial one in any SCADA project. It is here the business case for the project is conceived to determine initial feasibility. The scope of the project is essentially defined at this point. Initiation: validate project need; establish concepts and scope; establish Summary Work Breakdown Structure; conceptual estimate (-30 to +50%). At this stage some small amount of funding has been approved to undertake the preliminary investigations, and prepare a preliminary project management plan. It will be necessary to firm up on the scope, identify the main technologies to be used, and gain agreement and approval of the potential users of the system. Sufficient work needs to be done to enable a cost estimate to be prepared that is accurate to within -30 to +50%. Similarly sufficient work needs to be done to establish the benefits of the system to enough accuracy to convince management to give approval to proceed to the next phase. A common mistake at this point is to go into too much technical detail. The work at this stage should be concentrating on the functional (or user) requirements, and the technological requirements should only be looked at to the point of enabling cost estimates to be produced. The emphasis should be on ensuring that there is a common understanding within the end users of what functionality the system will provide. If the system is being introduced to improve productivity, then it is important that user management understand how they can use the SCADA system to change work practices. It is important at this stage that the project team includes someone from the end user part of the organization to begin to build a sense of ownership of the system. This involvement should continue throughout the project so that the system can be handed over on completion to an operator who is committed to using it to its full potential. Definition: appoint key team members; establish a preferred option (if not already done); develop baseline and schedules for project management; assess risks studies (ex. value management, economic); develop contracting strategies; develop implementation strategies; definitive estimate -15 to +25%; Go/No-go decision. At this stage the project is starting to get serious. A project team is in place, and organizational and reporting processes are established. The scope is being finalized (which sites, which functions, etc). Firm decisions are being made on contracting strategies such as design and construct, etc. The work at this stage should still be concentrating on the functional (or user) requirements, and the technological requirements should still only be looked at to the point of enabling cost estimates to be produced. Site audits should normally be conducted at this stage to avoid nasty surprises in the future. It is important at this stage to firmly identify the benefits of the system, and to develop "benefit realization plans". These plans will identify exactly how the proposed benefits will be realized; what changes will be made to existing processes to achieve the intended benefits. This will give management confidence that the investment is going to be worthwhile. Design: design reviews; definition report reviews; funds justification; design estimate - 10%+10%. If using a design and construct approach, then this phase normally involves preparing the specification, and developing contractor evaluation plans. It is probable that a prequalification phase could proceed at this time to overlap the tender preparation, and the prequalification phases. Prequalification is used to preselect reputable contractors who have a proven track record in this field, and should always be undertaken. Prequalification allows the selection of potential suppliers before they have submitted a priced quotation, on the basis of their capability and experience. Without prequalification you run risks of having to reject inappropriate contractors in the tender evaluation, and if your contractor documents are not well prepared you can end up in a difficult position. Acquisition: specification and working drawing preparation; pre-construction estimate (after receipt of tenders) -5%+5%; procurement; construction; off-site fabrication; commissioning; practical completion.

5 Under design and construct contracts, all the detailed work is carried out by the supplier(s), but preferably only one. Resist all suggestions to split the work, one contract for the communications network, one for the SCADA. Every time the work is splitted, supplementary risks are taken. For example, if the radio system does not perform, the radio contractor is responsible? If it meets the technical specification, then one has problems with both contracts. In this phase the project will go through a number of phases: Design (culminating in a design report from the supplier for approval) Configuration of SCADA master software Development of custom software Assembly of RTU's in factory, and testing Field installation of instrumentation, communications, and RTU's Commissioning Site acceptance testing Customer training Subsequent to this, the system normally has a defects liability period, and beyond that maintenance must be contracted for. Project Closeout: Project Final report; closeout of any outstanding defects and nonconformities; Final completion; post implementation review (PIR) as required. The post implementation review is something that is probably rarely undertaken, but should be a mandatory part of all projects. It is important that an assessment be made of how well the system is meeting the organizations needs as they are now understood. What needs to be done now to remedy these "faults"? Remember as far as the contractor and project team are concerned, these are not faults - the system has been delivered as specified. If it is likely that the project implementing organization will be undertaking future SCADA projects, then the PIR can be used to document any lessons learnt to avoid repeating the same mistakes. CONCLUSIONS We need to apply our knowledge to the fundamental redesign of our technologies in order to be able to bridge the current gap between research and economy [7], as well as between human design and the sustainable systems of nature. We consider that the innovation gap is a result of structural and behavioral mechanisms. According to [8] the ability to manage knowledge and information effectively and efficiently has been central to performance improvement in many industries. It is suggested, also, that information and communication technologies have often formed the underpinning technologies upon which new processes have been built. In the current research project and transfer to industry based paradigm, knowledge does not flow well between organizations and sometimes within organizations, too. In the case when the knowledge is socialized, externalized, combined and internalized only within an initial group of users, the tacit knowledge required to drive the process of adoption of the new technology doesn t flow effectively within or between organizations. In the knowledge conversion process, realizing the benefits of created knowledge rests on externalization and amplification through dynamic interactions between all four modes of knowledge conversion. Realizing the benefits of knowledge might prove extremely useful when implementing an up to date technology, such as SCADA systems, in the agriculture field. Often SCADA is not rigorously justified but simply required by management as being part of the way management wants to run the business. This may be the best way, as often substantial resources are consumed attempting to provide a justification for SCADA, and it is extremely common that after the system is installed, unexpected benefits arise that overwhelm the originally predicted benefits. In addition, the benefits may arise because of SCADA and several other key initiatives which are proceeding in parallel, and it is impossible to separate the benefits of SCADA from the benefits arising from other initiatives.

6 In any event the decision as to whether to proceed with SCADA will often arise directly out of the management philosophy. A progressive management will create a climate in which staff will actively seek ways in which to improve the productivity of the organization. In other organizations, every such proposal will be treated with skepticism. The key to this is for management to have developed a vision of how they want the organization to run in the future. If they have this, then it is likely this will encompass automation, SCADA, IT, for example, in order to become more efficient. BIBLIOGRAPHY 1. Brown, L.T., Building a Sustainable Society, W.W. Norton &Co, Ltd. Publishing House, US, United Nations. Report of the World Commission on Environment and Development Our Common Future, General Assembly Resolution 42/187, 11 December Cernea, M. M., A. H. Kassam, Researching the Culture in Agri-Culture: Social Research for International Agricultural Development, CABI Publishing, Oxford Press, Raman, S., Agricultural Sustainability: Principles, Processes, and Prospects, Haworth Press Inc.,U.S., E. Hazelkorn, University Research Management: Developing Research in New Institutions, OECD Devlin, K., Infosense: Turning Information into Knowledge, W. H. Freeman & Co Ltd., Nonaka, I, A Dynamic Theory of Organizational Knowledge Creation, Organization Science, 1:5, pp.14-57, GRIGORAS Mircea Adrian, E. MERCE, F. ARION, Oana GUI, D. ARION, Managing personality differences in interdisciplinary projects, 1 st International symposium on the history of electrical engineering and of tertiary - level engineering educational, Tomul LII(LVI), Fasc.5, Stiinte Socio- Umane, pag , octombrie 2006, Universitatea Tehnica Gh. Asachi, Iasi 9. Mircea Adrian GRIGORAS, Agatha POPESCU, Cosmin HOLEAB, Veronica CHEDEA, Emilian MERCE, Bridging the innovation gap and the management of interdisciplinary project for sustainable development, XXXVII Annual Meeting of European Society for New Metohods in Agricultural Research, ESNA, , Dubna, Rusia, in press