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The programme presents a broadly based review of the sources and utilisation of geothermal energy in Europe.
Metadata describing this Open University video programme
Module code and title: S237, "The Earth, structure, composition and evolution"
Item code: S237; 09
First transmission date: 18-07-1981
Published: 1981
Rights Statement:
Restrictions on use:
Duration: 00:25:00
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Producer: Barrie Whatley
Contributors: Geoff Brown; Ian Holm
Publisher: BBC Open University
Keyword(s): Aquifer; Geothermal energy; Geysers; Paris basin; Thermal baths; Volcano
Footage description: Over an animated, cut-away diagram of the earth, and of shots of lava fountains,Geysers and boiling mud pools, commentary by Ian Holm introduces the programme. Over shots of hot springs, thermal baths and a cross section animation of the earth, Ian Holm briefly lists some common elements of all sources of geothermal energy. Shots of the Tuscan Hills, of bubbling mud pool and of an electricity generating station in Larderello. Geoff Brown gives a brief history of the exploitation of geothermal energy in this area of Italy. Geoff Brown goes on to describe the geological evolution of the Tuscany area. Animated diagrams and shots of rock outcrops illustrate his points. He explains, particularly, how the aquifers which provide the geothermal source, have formed. Geoff Brown next explains how geophysicists locate and evaluate sites for geothermal exploitation. Shots of drill rigs working while he talks. With the aid of animated diagrams and rock samples, Geoff Brown describes the aquifer zone in the Paris Basin which provides low enthalpy energy and is located in a zone which is not volcanically active. Geoff Brown goes on, with the aid of animations, to discuss heat flow and its measurement through the lithosphere. Also shots of rock samples being tested for degree of heat transport ability in the laboratory. Shots of greenhouses at a horticultural establishment near Orleans. Commentary explains that the low enthalpy energy obtained from the aquifers here is used to heat the greenhouses. With the aid of an animation, Geoff Brown explains the problem of balancing the amount of hot water extracted from a low enthalpy source with that of cool water re-injected so that the aquifer is not exhausted. The programme goes on to examine the hot dry rock method for extracting geothermal energy. The method is being tested in Cornwall. Geoff Brown looks first at the geothermal properties of the granites found there. With a gamma ray spectrometer he determines the proportions of the radioactive isotopes in the rocks and from this data calculates the rock temperature at about 5 km. depth. Geoff Brown, at a quarry in Cornwall, looks at a site where test boreholes are being drilled. He explains how, by using the hot dry rock method, energy will be extracted from these rocks. Animated diagrams illustrate the theory behind the technique. Over shots of the quarry above, of a map of Europe and of animated diagrams, Ian Holm summarises the programme.
Production number: FOUX113K
Videofinder number: 1597
Available to public: no