Topical - Geothermal energy Potential of geothermal systems in Picardy Estelle Dourlat* Geothermal systems are not only about La géothermie ne concerne pas seulement Los sistemas geotérmicos no sólo se refieren electrical plants or urban heating networks, les centrales électriques et les réseaux de a plantas eléctricas o redes de calefacción but also concerned with geothermal energy chaleur urbains, mais également la géo- urbana, sino también a la energía geoté- assisted with a heat pump. In the former thermie assistée par pompe à chaleur. Dans rmica asistida por una bomba de calor. region of Picardy (North of France), 97% of l’ancienne région Picardie (dans le nord de la En la antigua región de Picardía (Norte the territory is suitable for very low tempera- France), 97% du territoire est favorable à la de Francia), el 97% del territorio es apro- ture geothermal power. The French Agency géothermie très basse température. L’ADEME priado para la energía geotérmica a muy for the Environment and Energy Manage- (Agence de l’Environnement et de la Maîtrise baja temperatura. La Agencia Francesa ment and the Picardy Region decided in de l’Energie) et la Région Picardie ont décidé para el Medio Ambiente y la Gestión de la 2016 to finance a facilitator to encourage de financer une mission d’animation en géo- Energía y la Región Picardía decidieron, en geothermal use. To carry out this aim, it thermie il y a un an. L’animateur connaît le 2016, financiar un sistemapara fomentar is important to consider the geothermal contexte géothermique en Picardie, avec la el uso de la energía geotérmica. Para llevar context in Picardy, its regulation and the réglementation et le potentiel, mais égale- a cabo este objetivo, es importante consid- potential, but also the local tools available, ment les outils locaux comme le recense- erar el contexto geotérmico en Picardía, su such as an inventory of geothermal installa- ment des installations de géothermie ou la regulación y el potencial, así como las her- tions or training sessions for architects. The formation pour les architectes. La mission ramientas locales disponibles, tal como un objective is to help increase the number of consiste ensuite à aider à l’augmentation inventario de instalaciones geotérmicas o geothermal projects in Picardy. du nombre de projets de géothermie en sesiones de formación para arquitectos. El Picardie. objetivo es ayudar a aumentar el número de proyectos geotérmicos en Picardía. hen we hear about geother- sibility to create geothermal electrical plants Atlas of the French Bureau of Geological mal systems, we usually pic- and there are only a few cities suitable for and Mining Research (BRGM), there is a ture electrical plants or urban a geothermal urban heat network, mainly real potential for this kind of geothermal Wheating networks. But high near-surface in the south of the region (Analy, 2013). project, with 97% of the territory suitable underground temperatures are not avail- Indeed, only for 23 cities do all three major for very low temperature geothermal power able everywhere. In the North of France, factors occur: high thermal consumption (Maton et al., 2012, volume 1). the former region of Picardy (now included (linked to the population density), high in the new region called Hauts-de-France, enough temperatures, and sufficient flow French Mining Code reform gathering together the former Picardy and rate of the Dogger (a geological formation former Nord-Pas-de-Calais Regions) is a whose aquifer can reach 70 °C and 160 m3/h The French Mining Code was reformed perfect example. Indeed, 97% of the ter- in southern Picardy). in 2015 (Decree n°2015-15) concerning ritory is suitable for very low temperature As 23 cities creating an urban heat very low geothermal heat projects called geothermal power. This article describes network by 2020 is not likely, the French Geothermal installations of Minimal the geothermal context in Picardy, the tools Agency for the Environment and Energy Importance (GMI). If the geothermal instal- available, key actions already taken and the Management (ADEME) and the former lations meet some criteria, the project for- promotion of shallow geothermal use. Picardy region turned their attention to very malities are simplified. low temperature projects to enhance geo- For geothermal probes and water table, Geothermal context in Picardy thermal heat production. For that, they lead the criteria are: different programmes described further in • boreholes less than 200 m deep, Environmental objectives and geothermal this article and also propose different pos- potential sibilities of funding for the projects. • power taken from underground Very low geothermal energy (Maton et amounting to less than 200 kW. Following the Grenelle Environment al., 2012, volume 2) is assisted with a heat Forum in 2007 and the law “Grenelle II” pump, as the extracted temperatures are Extra criteria for water table systems are: in 2010, Picardy was given some ambi- often below 25 °C. It can work with geo- • water temperature below 25 °C, tious objectives: to multiply by 21 times its thermal probes (also called a closed loop) • flow rate less than 80 m3/h, actual geothermal heat production by 2020 or with a water table (open loop) and finally • water is returned to the same aquifer (SRCAE, 2012). In Picardy, there is no pos- gives about 45 °C to a building’s heat. It can it was taken from. cover heating or cooling needs of collectives * UniLaSalle in Beauvais, Of course, there may be some additional (pools, schools, etc.) and private (office) local specific constraints such as protection [email protected] buildings. According to the Geothermal European Geologist 43 | May 2017 25 zones of drinking water wells. • The whole geothermal heat produc- is not so easy to exploit, the strategy is to The last element to take into account tion in Picardy is estimated at 1238 create a number of little projects with very is the administrative constraint map, TOE (14.4 GWh), with 77% of it low temperature geothermal installations. drawn up by the BRGM with methodol- The role of the facilitator is to boost and coming from public/private instal- ogy described in Herbaux et al. (2013) and structure the sector, linked to the develop- lations. located on the website Geothermie-per- ment of renewable energies in the region, spectives (ADEME BRGM, 2015). This map by: Architect training shows three different possibilities for both geothermal loops (closed or open): a green, • improving and promoting commu- Another action was the creation of a pro- orange or red square. If the square is green, nication about very low geothermal fessional training course for architects about there are no administrative constraints and systems and associated technologies, possible geothermal uses in construction and the project is only subject to registration. If renovation. This training was proposed by • improving communication among the square is orange, declaration is required, Afapi (a local training organism for archi- the different actors, but a hydrogeological expert must approve tects) and conducted by Ecome, an engineer- • offering free technical advice for it. For a red square, an authorisation request ing consulting firm. project managers (not including pri- is necessary. This training allows architects to become vate individuals) with pre-feasibility familiar with the administrative and regula- Tools available and keys actions already studies. tory aspects of geothermal projects, as well done In one year, the facilitator was requested as the different actors of the sector. They are to carry out 18 potential or pre-feasibility also taught some technical notions, and an Inventory studies; 2 of these led to more complete economic scale to projects is given, along feasibility studies and 8 are still on-going with possible sources of funding. In the frame of geothermal development due to a lack of information on the project Two training sessions took place in 2016, in Picardy, ADEME Picardy, in partnership or their recent start. in January in Soissons (Aisne) and in April in with the Regional Council, commissioned Amiens (Somme). Other regions of France the Geother engineering consulting firm to Maps from the inventory have asked for the same training (Grand-Est carry out an inventory of geothermal instal- in June 2017, for instance). lations in the former region. The goal was to Based on the inventory of geothermal know precisely the number of geothermal installations in Picardy, maps were cre- Audit of geothermal installations in progress installations in Picardy, with their technical ated (Figure 1) (Dourlat, 2017), showing in Hauts-de-France characteristics. It also aimed to update the different things: geothermal figures of the Energy, Air and ADEME Hauts-de-France (the new region Climate Regional Scheme (SRCAE, 2012) Geothermal installations exploited on 31 including former Picardy and former Nord- of Picardy and change the environmental December 2015 in Picardy (public/private Pas-de-Calais) commissioned the Ecome objectives concerning geothermal systems. institutions). engineering office to audit 19 geothermal The inventory consisted of a quantitative Most of the geothermal projects run- installations of the region (10 in Picardy and part for private individual installations and ning were carried out in Somme and Oise 9 in Nord-Pas-de-Calais). Beyond the 19 dif- both a quantitative and qualitative part for and there is an overwhelming majority of ferent analyses and advice for improvement, public/private installations. open loop geothermal projects. As men- the aim of this study is to make a crossing Based on the inventory results (Geother, tioned above, this could be explained by analysis of installations and find the main 2016), the main conclusions are: the relatively recent appearance of probe defects that can occur in very low tempera- technology. Concerning the geological • The geothermal sector is less devel- ture geothermal installations.