| Keywords |
direct use, germany, distict heating, pricing, greenhouse, tomato, peppers, special award, opportunity cost approach, |
| Abstract |
The German Molasse Basin in the south of Germany harbors an enormous geothermal potential. Temperatures in the aquifers range from 70°C to 160°C, rendering the region an excellent location for deep geothermal energy projects. A perfect example for the technical and economical use of geothermal energy in this region is the award-winning project in the municipality of Kirchweidach, a 2,500-inhabitant town in southern Bavaria. In Germany, this project was the first to provide an agricultural business with geothermal heat energy via a local district heating network. In 2011, the project started with a doublet drill for the production well (with a depth of 3850m and a length of 5133m), and an injection well (with a depth of 3800m and a length of 4937m) in the north of Kirchweidach. The hot water temperature of the production well is approximately 125°C and supplies the in 2014 newly built district heating network of the small town as well as one of the largest greenhouse in Bavaria with CO2-free heat energy. The district heating network supplies private homes and public buildings with an annual heat demand of 13 GWhth as well as the whole greenhouse with an annual heat demand of 108 GWhth with CO2-free heat energy. This 20 ha large greenhouse was built in 2014 by a vegetable farmer near the drilling place. A steady supply of renewable base-load heat energy from the geothermal plant supplying the greenhouse makes it possible to farm bell peppers, tomatoes and strawberries all-year round. Tomatoes from this one greenhouse now accounts for a fifth of all tomatoes sold by a major German supermarket chain in the state of Bavaria. In addition to the saved fuel of nearly 7.5 Mio. liters per year for the greenhouse, round about 1.5 Mio. of transport-kilometers due to imports from Spain and the Netherlands can be avoided. Bavaria increased its self-sufficiency with tomatoes from 7% to 11% and pepper bells from 2% to 7%. The constant heat demand of the greenhouse is a perfect use of the potential of geothermal energy. To ensure a high connection density in the district heat network for the economic and ecological success of the project, a high acceptance of the inhabitants of the small town was necessary. This was accomplished by informing the inhabitants about used technologies, and about required steps throughout all project-phases since the early stage of the project. They were also informed about the involvement of the greenhouse and an innovating heating price system, which caused a high acceptance. The innovative heating price system is based on an opportunity cost approach. For determining the heating price, the price system takes foregone electricity sales for feed-in tariffs under the German Renewables Act for the operator of the power plant into account. Additionally, the outside temperatures, which have a significant impact on the efficiency of the electricity generation unit, are also considered. This opens up the possibility to extract a variable volume flow to supply the district heating network, while generating electricity without affecting the operator of the power plant adversely. N.B. We prefer to deliver an oral presentation on this topic rather than present it on a poster. Our reason for this is that a poster presentation does not do the importance of economic aspects of deep geothermal projects justice. Securing sufficient funding is the single biggest obstacle to more widespread deep geothermal energy development worldwide to date. Yet, economic topics like financing have been playing a surprisingly small role at conferences worldwide over the past few years. For the future progress of the technology, however, we consider it essential to attract investors who are willing to invest the substantial sums necessary for geothermal development by making the economic case for deep geothermal energy projects and presenting case studies. Their interest and motivation can, however, only be stirred if the topic of deep geothermal energy is presented in terms they understand and can act upon. In our humble opinion, the industry as a whole should place equal importance on the technology itself and on its economic realities. Neither aspect can be ignored if we want to accelerate deep geothermal development. We believe that placing equal emphasis on the economic aspects of deep geothermal energy, especially funding and attracting investors, as has been placed on the intricacies of technical aspects in the past is necessary for the technology to develop to the extent and within the timeframe that we all envision. As the leading professional services firm in the deep geothermal energy industry worldwide, we are well versed in arbitrating between investors and developers. Calculating a variety of investment and exit scenarios as well as cooperating with investors on behalf of developer companies on a daily basis gives us profound insight into the investor mindset and the kind of information that motivates them to invest in deep geothermal energy technology. Thank you for considering the above topic for an oral presentation. |