Page 60 - ITA Journal 3-2018

Technical Papers
Munich relies on geothermal energy
SWM plans to make a long-term switch to renewables for dis- trict heating. The public utilities company aims to make “further substantial improvements in the already excellent climate and resource track record of district heating. Due to the unique nature of Munich‘s location and that of the region, geothermal energy will play a key role in this context: there is virtually no other region in Germany where the geological conditions are as favourable as they are here“.
Optimal conditions for the South German metropolis: “Munich is located right on top of a huge reservoir of this natural energy source”. At a depth of 2,000 to
over 3,000 metres, water tem- peratures reach from 80° to over 100° Celsius. Heat from these geothermal water sources are ideal for heating. To bene t from this source, hot water is pumped to the surface and channelled through heat exchangers, which extract the heat from the thermal water. The cooled water is then fed back into the subterranean reservoir. “The geothermal power cycle thus does not impact on the eco-system,” states SWM.
Holzkirchen plant online in 2019
Munich has made extensive plans, and will implement them in the next few years. A further geother- mal plant will be constructed on the site of the heating and power plant “HKW Süd”. It will go online already at the end of 2019. SWM expects the thermal water to have temperatures above 95°C. The plant is at the intersection of three grids: up to 50 megawatts could be fed into the grids inner- city, Sendling and Perlach. SWM plans to construct three addi- tional geothermal plants by 2025.
In Holzkirchen, situated in the Bavarian Molasse Base, a fth ORC (Organic Rankine Cycle) is being planned. The electric capacity will be 3.4 MW, and be utilised as a power source especially during summer. In winter, the heat will in turn be used for district heating. The Holzkirchen geothermal power plant is scheduled to go online in the rst quarter of 2019.
High discovery rates
Daldrup & Söhne, a company spe- cialising in drilling and geothermal exploration, has paved the way for utilising geothermal heat in the Dutch drilling project Nature’s Heat. Drilling con rmed a capac- ity of at least 110 litres a second,
and a thermal water tempera- ture of ca. 86° Celsius. As such, the “value is well above the pro- jected average value,” reports the company. The future operator will be able to utilise 20 MW thermal power, instead of previously cal- culated 12 megawatts power for heating greenhouses. Natural gas will be extracted as a by-product in parallel, with around 1.2 times the volume. The gas will be sep- arated and be used to produce electricity by a third party. Thanks to the speci c discoveries, the entire project is viewed as being ef cient above average.
Geothermal energy has long left the starting block. Even though, this type of energy still remains at the very beginning of its poten- tial, while making itself warmly recommended as a renewable source of energy. The more reliable pumps will become as an essential and expensive component, the more attractive geothermal power will become. A further, important piece of the mosaic, without a doubt.
Messe Düsseldorf GmbH
Stockumer Kirchstr. 61 40474 Düsseldorf Germany
Petra Hartmann-Bresgen, M.A.
Tel.: +49 (0)211 4560-541 Fax: +49 (0)211 4560-87 541
HartmannP@messe- duesseldorf.de www.messe-duesseldorf.com
ITAtube Journal No3/October 2018
60