Geothermal energy is an energy source with potential to supply mankind with both heat and electricity in nearly unlimited amounts. Despite this potential geothermal energy is not often considered in the general energy debate, often due to the perception that it is a margin energy source bound to a few locations with favorable geological conditions. Today, new technology and system concepts are under development with the potential to extract geothermal energy almost anywhere at commercial rates. The goal of these new technologies is the same, to harness the heat stored in the crystalline bedrock available all over the world at sufficient depth. To achieve this goal two major problems need to be solved: (1) access to the depths where the heat resource is located and (2) creation of heat transferring surfaces and fluid circulation paths for energy extraction. In this thesis a novel concept and method for both access and extraction of geothermal energy is investigated. The concept investigated is based on the earlier suggested idea of using a main access shaft instead of conventional surface drilling to access the geothermal resource, and the idea of using mechanically constructed 'artificial fractures' instead of the commonly used hydraulic fracturing process for creation of heat extraction systems. In this thesis a specific method for construction of such suggested mechanically constructed heat transfer surfaces is investigated. The method investigated is the use of diamond wire cutting technology, commonly used in stone quarries. To examine the concept two heat transfer models were created to represent the energy extraction system: an analytical model based on previous research and a numerical model developed in a finite element analysis software. The models were used to assess the energy production potential of the extraction system. To assess the construction cost two cost models were developed to represent the mechanical construction method. By comparison of the energy production potential results from the heat transfer models with the cost results from the construction models a basic assessment of the heat extraction system was made. The calculations presented in this thesis indicate that basic conditions for economic feasibility could exist for the investigated heat extraction system.

L'expérience perçue lors de l'utilisation de produits est récemment devenue un facteur différenciateur majeur entre les principaux acteurs de l'industrie. Elle influence désormais grandement le succès de nouveaux produits. En parallèle, l'intérêt de la communauté de recherche en design sur le sujet va en grandissant. La présente recherche apporte une contribution à ces deux mondes en explorant des moyens de définir et représenter des intentions d'expérience utilisateur. Une des originalités de cette recherche réside dans le fait que son assise théorique combine les notions complémentaires d'expérience utilisateur et de processus « kansei » (processus mental affectif) utilisées originellement par des communautés scientifiques différentes. Elle fait aussi partie du groupe très restreint de travaux qui investiguent les liens entre ces considérations et le monde industriel.Au long des cinq expérimentations qui composent ce mémoire, j'explore la création d'outils et de méthodologies s'intéressant au processus kansei des futurs utilisateurs et permettant l'élaboration puis la communication d'intentions venant nourrir le processus de conception de nouveaux produits. L'influence de la nature des représentations amont sur la compréhension réciproque au sein d'équipes de conception multiculturelles (multi-nationalité et disciplinaire) ainsi que sur différentes typologies de projets prospectifs centrés sur l'expérience sont aussi mis en avant. En termes de contributions académiques, cette recherche a permis de modéliser l'information design échangée au sein d'équipes de conception visant à impacter les processus kansei des potentiels futurs utilisateurs. Elle a aussi mis en valeur les qualités et l'importance des représentations amonts multi-sensorielles. Les contributions industrielles couvrent quant à elles, la création d'outils, de méthodologies et de représentations amonts permettant de caractériser l'approche dite du « Kansei Design », et d'établir des liens entre ces différents aspects et trois typologies de projets de développements de nouveaux concepts. / In the industrial context, users' experience with products recently became a major differentiation factor between competitors and can greatly influence the success of a product. In parallel, the interest from the design research community about this topic is also growing. This research intends to contribute to both contexts by investigating the definition and representation of user experience intentions. When defining the theoretical background of this research a link will be created between the complementary notions of user experience and kansei process. Based on this original field of study, this dissertation will discuss design activities undertaken by design teams in order to nourish the much wider industrial design process.With the five experiments that will be presented in this dissertation, I will explore the creation of tools and methodologies centred on potential users' kansei process and supporting the creation of intentions related to the user experience of products to be designed. I will also investigate how the nature of the resulting early representations can impact reciprocal understanding within multi-cultural design teams, and finally how the developed approach (Kansei Design approach) can impact different typologies of new concept development projects.In terms of academic contributions, this research enabled to model the exchange of kansei-related design information among design-teams and highlighted the added value of multi-sensory early representations resulting from experience-centred design activities. Regarding industrial contributions, the different experiments made it possible to characterise the Kansei Design approach in terms of tools, methodologies, and early representations. Moreover a link was established between the different characteristics of this approach and three typologies of new experience-centred concept development projects leading to different products development projects.