Morahalom is a small town (pop. 5800) situated in the south of Hungary on the border with Serbia. It used to be listed among the 50 most disadvantaged communities of Hungary, but the investments of the past decade - upon some the current project also builds on - launched it into the top 10 most dynamically developing settlements. The installation of the geothermal district heating system can be considered the most influential and of highest impact of them all, which also presented a solid foundation to the local GEOCOM components. It is worth noting that there are two separate geothermal heating systems in place in the town. One of them was developed solely for balneological use at the local spa, the already mentioned district heating system has a much wider impact on the community. Some key specifications of this latter have to be highlighted.
The doublet configuration of one abstraction well (B-45) and one injection well (B-46) (1270m and 900 m respectively) allows the sustainable resource management of the 63°C thermal water produced on site from the Upper Pannonian sandstone reservoir with flow rates in the range of 25-30m3/hour in summer and 60m3/hour in winter. The annual thermal water production on this system is around 190.000m3. The full loop runs a total of 3,054 kms between the two wells serving with heat and domestic hot water (DHW) a total number of 12 municipal-owned public buildings mainly in the downtown area. By having the geothermal cascade system in place the proportion of renewable energy within the energy mix of public institutions has grown from 0% up to more than 80% - offsetting the use of 542.029 m3 natural gas annually, while providing 18.700GJ of heat per year. As a direct result annual heating-related emissions have also been reduced significantly (by 1590t of CO2, 585kg of NxOx and 1113kg of CO). The GEOCOM project aimed to improve the cascade system with a set of new elements to ensure total utilisation of geothermal energy and to demonstrate cutting edge energy efficiency/retrofitting measures that are currently lacking from geothermal projects in Eastern-Central Europe.
Some key public institutions and buildings (cultural centre, elementary school, sports hall and kindergarten) were involved in the complex retrofitting campaign which’s primary aim was to reduce the operational costs, resulting in significant savings at the owner municipality’s annual budget. The total floor area of the subject buildings (dated between 1935 and 1972) was up to 2000 m2 and their combined annual natural gas consumption for heating and domestic hot water purposes was in the range of 130-140.000 m3, which translated to 85% of their overall operational costs. Read more
The exceptionally poor energy efficiency of the building envelopes (average of 130-210 kWh/m2/yr, one structure with 590 kWh/m2/yr) was coupled by very outdated building engineering solutions such as boilers with diffusion burners and far greater capacity than the actual heat demand. It was evident that major savings can be realized by connecting these estates to the new cascade system and by installing additional renewable energy sources (solar thermal panels) to complement the geothermal base load the traditional natural gas-based features will be rendered to serve only as backups in the future.
By delivering a fairly standard energy upgrade of the selected buildings first the doors and windows were replaced followed by the insulation of the building envelopes using 10 cm polistyrol slabs. These measures only combined with linking up to the geothermal cascade system would have already resulted in a drastic savings, but the overall efficiency was improved even further by installing 121m2 solar thermal collectors (TS 300 Flat Plate type) on the rooftops to cover with ease the daily demand at the target buildings. It is worth mentioning that Morahalom is not only very fortunate with is setting in terms of it subsurface geothermal resources, but the south of Hungary also excels regarding the most intensive solar radiation and the highest number of annual sunny hours (~2000/a) in the country as well.