Meeting of Power Industry Cooling Water Specialists

The PICWS meetings provide a platform for cooling water specialists in Europe to discuss a variety of topics. As the strong bias of the meeting is deliberately technical rather than commercial, the attendees have the opportunity to share knowledge and freely discuss the application of (sometimes novel) technologies, operational issues and legislative aspects with their peers. These interactions have proved to be very valuable and resulted in a number of collaborative projects that have served to both update the current state of knowledge in various areas and offset potential regulatory risks. Next to the content of the meetings themselves, the PICWS activity provides the opportunity to build and maintain a network of cooling water specialists across Europe.

The first meeting of this group was organized in 1993 by Nuclear Electric (NE) and KEMA at NE’s offices in Gloucester, UK. The meeting focused on the formation of cooling water by-products and current alternatives in biofouling control and was attended by NE, ENEL, EdF, Laborelec and KEMA and a representative of AKZO-NOBEL and DOW Benelux. This meeting was such a success that it was decided to organize regular, once a year, meetings as a workshop.

Due to the type of work, largely involving the biological aspects of cooling water use, a practice nearly completely dedicated to electricity production, invitations were subsequently extended to a wide range of participants across Europe and around the Mediterranean. The first workshop was organized by ENEL and KEMA in November 1994 in Rome. To give it official status this was organized under within the CORECH framework where the attendees of the meeting were recognized as an accredited ‘group of experts on cooling water biology’. Since then, PICWS meeting have been held in 1995 (Madrid, Spain), 1997 (Paris, France), 1998 (Dublin, Ireland), 2000 (Esbjerg, Denmark), 2002 (Hunterston, Scotland), 2005 (Golfech, France), 2007 (Ravenna, Italy), 2009 (Linkebeek, Belgium), 2012 (Arnhem, Netherlands). In 2016 the 11th PICWS meeting was held at the EdF R&D center in Chatou, France from 28 – 29 January 2016. The meeting was attended by 61 representatives from the following companies: Sweco (Netherlands), Laborelec/ENGIE (Belgium), EdF (France), ENGIE (France), Uniper Technologies Ltd (UK), EDF Energy - New Nuclear Build (UK), EDF Energy Generation (UK), Enel Ingegneria e Ricerca spa (Italy), Veolia Industries Global Solutions / Ginkeo (France), Veolia Water Technologies (France), Veolia Environnement Research & Innovation (VERI) (France), Gate Terminal (Netherlands), AREVA GmbH (Germany), RWE Generation (UK), RWE Power AG (Germany), E.ON Kernkraft GmbH (Germany), VGB (Germany).

PICWS meeting topics 2016

1. Regulations on pathogens and chemicals around Europe and
2. Cooling water issues of the future. These round-table discussions proved useful to all concerned.

The first discussion, on the regulations governing pathogen control in cooling water circuits, focused on the application of indicator levels. Currently there is a strong focus on concentrations (cfu/L, colony forming units) in the water phase, whilst there is an actual need to focus on mitigation of biofilms on the surfaces. In addition, there is still a high level of variance in measured cfu/L levels between laboratories, results showing variation with factors 10 – 100. There is no clear argument for the application of specific limit values vs action levels and in principle, using cfu/L as a measure to monitor Legionella presence, is always ‘behind the facts’ and not applicable for taking preventive measures. The application of efficient chemicals to mitigate biofilms and pathogens is limited by ELVs and special permits are required. In addition, a proper registration of cooling towers is lacking or not performed well and a difference between small and large scale cooling tower systems should be recognised. As a result, the current legislation in many countries does not encourage a proactive approach, i.e. keeping a high level of hygiene, by which pathogens can be controlled efficiently.

The second discussion on future cooling water issues focused on several items: impingement and entrainment, the appropriateness of using scarce water resource for evaporative cooling, discharges of heated effluent/cooling water and chlorination and EU directives on protected areas. It was mentioned that these were the topics of interest 20 years ago, and still are highly topical today and will be in the future. Chlorination, especially, involves a complex chemistry where we continue to discover more. Whilst the issues are the same as they always have been, societal attitudes and value may change over time. In the next few years we can expect to revisit the EU BREF on Cooling system choice and the arguments for and against wet cooling systems of different types will need to be set out clearly since the BREF will inform permitting decisions of the future. The changing role of thermal power plant in a system with increased renewables will need consideration in this content. It was mentioned that nowadays the dynamics of legislation/permitting processes are changed. The knowledge level with the legislative authorities is not sufficient and permitting officers often lack the ability to apply expert judgment and thereby lack the confidence to take decisions. This, in conjunction with widespread appeal to ‘the Precautionary Principle’ has led to increasingly extended and broad case-making requirements rather than focusing the efforts of regulators, stakeholders and applicants on the key issues. The cooling water specialists (such as gathered in PICWS) are the keepers of knowledge, and should be able to provide the knowledge to those who can benefit from it, thereby able to shape regulation. In some cases, where Water FD is the basis of environmental protection, the environment could be regarded as a competitor for use of scarce surface freshwater resource and in some areas the power sector may need to compete or co-operate with other users such as for public water supply and agriculture for that water not allocated to environmental protection. Modern guidance on Ecological Impact Assessment is suggesting that ‘baseline’ should be interpreted as ‘when the plant begins to operate’ which could be 10 years later than when the modelling and assessment activity for permit application is carried out. Thus establishing ‘the baseline’ is itself a predictive exercise. In addition guidance suggests the initial permitting stage should consider the potential impacts of the proposed plant through its operating life. This could be many decades. In some cases, such as modern nuclear plant with design life of 60 years, such assessment is confounded by the need to consider other changes that could occur over such timescales such as those due to climate change.

Future of PICWS

As the largely-privatized energy sector companies across Europe no longer support meetings of this kind, one of the proposals to the group was that PICWS be re-established as a professional platform with members. The membership fee is used to support the meetings and maintain a website for the use of the cooling water specialist network. This was agreed in principle and the next meeting is to be organized for the end of 2017.