Journal of Energy History Revue d’histoire de l’énergie AUTHOR Finn Harald Sandberg Condeeps. The Dinosaurs of the Norwegian Petroleum North Sea Museum, Stavanger (Norway) Abstract POST DATE When oil was found in water depths larger than 150 meters 03/06/2019 in the North Sea in the 1970s, a new and revolutionary ISSUE NUMBER concept was needed to be able to support deck structures JEHRHE #2 for production of petroleum. Norwegian entrepreneurs SECTION introduced a new design based on their experience with Energy sources large structures of concrete. The design, named Condeep, KEYWORDS was developed. For a period of 25 years this design became Oil, Heritage, Gas, Dam the dominant support structure for platforms placed in DOI water depths up to 300 meters. By early 1990s new tech- in progress nology had been developed and deeper waters were being challenged. The Condeeps could no longer with- TO CITE THIS ARTICLE stand the competition and the industry had no longer Finn Harald Sandberg, use for the giant structures. However, the world needs a “Condeeps. The Dinosaurs of symbol or monument over a very special period that may the North Sea”, Journal of come to an end sooner than we know. One such plat- Energy History/Revue form may be well suited for a UNESCO world heritage d’Histoire de l’Énergie – the Draugen platform in the Norwegian Sea. This article [Online], n°2, published 03 introduces the reasoning behind such a suggestion. juin 2019, consulted XXX, URL: http://energyhistory.eu/ Plan of the article node/136. → Concrete platforms for the North Sea → Designing Condeeps → Preserving one of the dinosaurs of the North Sea: why and how ISSN 2649-3055 JEHRHE #2 | ENERGY SOURCES P. 2 SANDBERG | CONDEEPS. THE DINOSAURS OF THE NORTH SEA 1 When Norway became an oil producing coun- try towards the end of the 1960s, only a few people expected that a Norwegian entrepre- neur company could become one of the largest subcontractors to the upcoming exploration of the North Sea – using concrete as a material in exceptional and giant structures. 2 Realizing what a great influence the oil indus- try has had for the development of economic and social life in Norway there have been sev- eral ideas how to preserve at least one of these structures for the future – when the fossil fuel era comes to an end. One platform - in my Figure 1: The Zakarias dam (completed 1969). Photography mind - Draugen, could be a strong candidate by Vidar Iversen [CC BY-SA 3.0]. for becoming an international monument and possibly gain status as a UNESCO world heritage In Norway concrete has been used as the main 4 status. Having spent more than 30 years in the material in dams built for producing electricity. Norwegian oil industry I have seen most of the Until the mid-1950s concrete was the dominat- technical progress that has been taking place. ing material and many companies were involved The most important structures are the huge in the big projects in the Norwegian mountains Condeeps (abbreviated from Concrete Platform (fig. 1). for Deep Waters). The time of the fossil fuels may be obsolete within this century, the petroleum A few years after oil was found in the Norwegian 5 industry has been the basis for the development part of the North Sea, Norwegian Contractors of modern Norway and the concrete structures (NC) was formed in 1973 as a Joint Venture of are unique pieces of design and construction. three large contractors and their idea was to utilize their joint experience, competence and resources and take advantage of the country’s CONCRETE PLATFORMS FOR THE NORTH SEA special topography with deep fjords and plenty 3 The first traces of a material that can have of raw material to produce structures special- some resemblance to concrete dates back 20 ized for this new industry.3 000 years. It was however the Romans, a little more than 2000 years ago, who really devel- The first ideas using concrete for oil extraction 6 oped the knowledge and competence of how were launched in 1970 by two of the co-founding to create huge buildings based on using ashes companies – and a concrete floatable platform from volcanoes as an important ingredient. The support was introduced (picture) shortly after. volcano ashes used in concrete were called poz- zolans after the city Pozzuoli, close to Naples A total of 17 giant structures were built in Norway 7 and Vesuvius, where the material was first col- by Norwegian Contractors (and the founding lected.1 Two hundred years ago, an industrial companies) during a period of 25 years. Most product named Portland cement was introduced of them were Condeeps based on the princi- overtaking the market from the natural poz- ple of standing securely on the sea bed only by zolans.2 the force of its own weight – a so called gravi- ty-based structure (GBS). 1 Ruth Whitehouse, John Wilkins, The Making of Civilization. History Discovered Through Archaeology (New York: Alfred A. Knopf, 1986). 2 Frederick Measham Lea, The Chemistry of Cement and 3 Øyvind Steen, På dypt vann. Norwegian Contractors Concrete 3rd ed. (London: Arnold, 1970). 1973 – 1993 (Oslo: Norwegian Contractors, 1993), 16. JEHRHE #2 | ENERGY SOURCES P. 3 SANDBERG | CONDEEPS. THE DINOSAURS OF THE NORTH SEA Figure 2: Høyer-Ellefsen’s first suggestion for a concrete platform structure (1970) – an early Condeep experiment. Source: Øyvind Steen, På dypt vann. Norwegian Contractors 1973 – 1993 (Oslo: Norwegian Contractors, 1993), 7. Figure 3: Table listing the 17 concrete platforms produced in Norway by Norwegian Contractors between 1973 and 1995. Source: Steen, På dypt vann. Norwegian Contractors 1973 – 1993 (Oslo : Norwegian Contractors, 1993). JEHRHE #2 | ENERGY SOURCES P. 4 SANDBERG | CONDEEPS. THE DINOSAURS OF THE NORTH SEA Figure 4: The remains of the concrete platforms left on Frigg field in the North Sea. © Total E&P Norge / Norwegian Petroleum Museum.​​ 8 Of the listed structures Ekofisk, the Brents and been made available for the NPM. Many of these the Friggs have already been decommissioned – are made publicly available at the site https:// but the concrete structures are left in the fields digitaltmuseum.no. – more than 3000 pictures with the deck structures removed (fig. 4).4 can be found using only Norwegian Contractors as search criterion. 9 The Norwegian Petroleum Museum (NPM) coop- erates with The Norwegian Oil and Gas Archives DESIGNING CONDEEPS (NOAGA) in documenting many of the large devel- opments on the Norwegian Continental Shelf. So From the list above one finds that the Condeeps 11 far five large Industrial Heritage Projects have came in many different shapes both in height been completed (Ekofisk, Frigg, Statfjord, Valhall and number of legs. Most of them were never and Draugen). meant to be removed, but some are designed for being towed back to the coast to be destructed. 10 In addition, NOAGA has received the complete The above mentioned Draugen is one of these. archives from Norwegian Contractors for the period between 1973 and 1995 when the com- There were several reasons for starting to build 12 pany was in existence. Altogether there is 16 concrete platforms in the North Sea. In the shelf meters of interesting material to be found. early 1970s, several huge discoveries of oil on All films and photos from the building, transport the British and Norwegian continental shelf, and installations of the concrete platforms have Beryl, Brent, Ninian and Statfjord were made, to name the largest. At that time, there were no 4 Adam Vaughan, “Shell begins huge task of decommis- marine structures such as “jackets” (large steel sioning Brent oil rigs”, The Guardian, 06/02/2017. Url : https:// www.theguardian.com/business/2017/feb/06/shell-decom- framework structures fig. 5) or floaters suitable missioning-… (accessed 17/05/2019) for building production facilities of 120m - 150m JEHRHE #2 | ENERGY SOURCES P. 5 SANDBERG | CONDEEPS. THE DINOSAURS OF THE NORTH SEA connected to the nearest pipeline as one moved further from the coast. In the North Sea, the most promising areas were situated far from the coastline both in the UK and in Norway and there were no pipelines available. The basic conditions and the marine environ- 14 ment are more demanding in the North Sea. Piling equipment designed for installation of steel platforms in the Gulf of Mexico, was inad- Figure 5: An example of a steel jacket – supporting structure equate for the seabed in the northern North Sea for oil producing facility in the North Sea. Source: Puput Aryanto with hard sand and clay layers formed by the Risanto, Introduction to Offshore Oil and Gas Surface Facilities (2015). URL: https://www.slideshare.net/PuputAryanto/ glaciers during the ice age. Without pipelines for introduction-to-offshore-oil-and-gas-surface-facilities. export, oil storage and offshore loading to tank- ers were necessary to uphold a consistent pro- duction under adverse weather conditions. There water depth in the North Sea. In addition, there were thus many challenges and opportunities was no infrastructure in the form of pipelines for that the industry faced when developing large exporting oil and gas from the platforms. oil fields in the North Sea. Norwegian indus- try, and Norwegian entrepreneurs, were active 13 In the 1960s the Gulf of Mexico was the refer- and inventive in promoting ideas and developing ence point for offshore oil and gas production. suggestions for new concepts. Høyer-Ellefsen However, there were several conditions that were and Akergruppen (two of the companies forming different in the North Sea. One of these differ- Norwegian Contractors in 1973) were involved in ences was that the production rate was con- a collaboration that proved to be very success- sistently higher from the North Sea areas.