In this book, the Commission of the European Communities presents the proceedings of the Workshop on Solar Central Receiver Projects, held in Varese, I taly , in June 1984. This Workshop was supported by all operators of solar tower power plants around the world and, as a result, these proceedings provide a comprehensive overview of the technology in its current state of development. The Workshop was organized by the Commission of the European Communities in the frame of the second solar energy R&D programme under the responsibility of its Di rectorate-General (X 11) for Science, Research and Development in Brussels. The meeting place, Varese, in Italy, was selected because of its neighbourhood to the Ispra Establishment of the Commission's Joint Research Centre who cooperated in the organization of the Workshop. Solar power plants of the central receiving type have two conflicting characteristics: they employ very simple and classical components but as a system they are of tremendous complexity. It was the hope for rapid progress by using available components that guided the decisions taken in the late seventies to build six large experimental plants: four in Europe, one in Japan and one in the United States. At that time, this technology enjoyed high priority in solar energy R&D around the world. Once the plants were completed, however, it became clear that the technical complexity combined with difficult meteorological conditions at most construction sites made the yields less favourable than anticipated.

(see English translation on page 13) L'HYDROGENE, GAZ DE GRANDE DIFFUSION ? par Monsieur Maurice LEGRAND *President des Houilleres de Bassin du Centre et du Midi, Paris Voici rnaintenant dix ans que Les concepts d'Hydrogene energetique ou d'Econornie, voire de Civilisation, de L'Hydrogene sont debattus et donnent Lieu a des prograrnrnes de recherche significatifs. Au rnornent d'ouvrir cette presentation des travaux du prernier prograrnrne de recherche sur L'Hydrogene ausein de La Cornrnunaute, je voudrais revenir rapidernent sur Le chernin parcouru et en degager quelques reflexions pour L'avenir. Et d'abord pourquoi est ne cet interet pour L'Hydrogene? Rappelons-nous Les analyses qui prevalaient il y a dix ans. A L'epoque Les hydrocarbures sont ornnipresents a des couts defiant taute concurrence. On prevoit Leur rarefactionprogressive s'accornpagnant de La rnontee concornitante des prix. C'est a cette releve ineluctable rnais Lente qu'il faut faire face et L'issue est attendue du nucleaire, un nucleaire au derneurant sans problerne d'acceptabilite, et dont Les couts bien rnaitrises Lui perrnettront de s'irnposer des que Les hydrocarbures arnorce- ront La rernontee de Leurs prix. Le problerne est des Lors de preparer cette penetration du nucleaire. -7- Par l'electricite d'abord puisque plusieurs filieres sont disponibles pour cela. Mais la substitution aux produits petroliers de l'electricite, qui est produit avec des rendements modestes, qui ne se stocke pas et qui ob- lige a des modifications dans les usages, apparait vite limitee.

The first crisis in energy prices was undoubtedly a strong stimulus for the involvement of the Commission of the European Communities in research and development on alternative energy sources. Indeed, the need to overcome difficulties faced by the Community as a whole, particularly those resulting from its severely unbalanced energy supply, made a common Community approach seem especially apt. This reasoning also applies to energy R&D, bearing in mind that responses to the crisis should be not only political or economic, but also scientific. Four years have passed since the decision of the Council of Ministers to launch the first Community Energy Research and Development Programme, dealing with geothermal energy, solar energy, hydrogen production and utili sation, energy conservation and energy systems analysis. A seminar on geo thermal energy was held two years ago to report on work in progress at the half-way stage of the four-year programme. The second international seminar, reported in this volume, was arrang ed so as to provide an opportunity to examine the final outcome of this Community investment in research in geothermal energy. This proceedings volume therefore has two main aims: - to present an evaluation of the results of the Community geothermal programme, by means of 83 formal reports describing the individual research programmes; - to show how the Community research programme fits into the overall context of national and international research on geothermal energy, by including the presentations of six guest speakers who introduced the sessions and gave keynote addresses."

Proceedings of the Third International Seminar on the Results of EC Geothermal Energy Research, held in Munich, 29 November-1 December, 1983

In this book, the Commission of the European Communities presents the proceedings of the Workshop on Solar Central Receiver Projects, held in Varese, I taly, in June 1984. This Workshop was supported by all operators of solar tower power plants around the world and, as a result, these proceedings provide a comprehensive overview of the technology in its current state of development. The Workshop was organized by the Commission of the European Communities in the frame of the second solar energy R&D programme under the responsibility of its Di rectorate-General (X 11) for Science, Research and Development in Brussels. The meeting place, Varese, in Italy, was selected because of its neighbourhood to the Ispra Establishment of the Commission's Joint Research Centre who cooperated in the organization of the Workshop. Solar power plants of the central receiving type have two conflicting characteristics: they employ very simple and classical components but as a system they are of tremendous complexity. It was the hope for rapid progress by using available components that guided the decisions taken in the late seventies to build six large experimental plants: four in Europe, one in Japan and one in the United States. At that time, this technology enjoyed high priority in solar energy R&D around the world. Once the plants were completed, however, it became clear that the technical complexity combined with difficult meteorological conditions at most construction sites made the yields less favourable than anticipated.

Proceedings of the 3rd International Seminar, held in Lyon, May 25-27, 1983