Content

Main aim of the GeoCOOL FOOD project is to apply an interdisciplinary approach (including geological, biological, technical, energetic and management aspects) for exploration of shallow geothermal energy potential and optimizing technological solutions that will ensure energy- and cost-efficient cold storage of vegetables. Leading research institutions cooperate within the project: Geological Survey of Slovenia (RO 215), Biotechnical Faculty of University of Ljubljana (RO 481) and Institute Jožef Stefan (RO 106).

The low self-sufficiency rate for vegetables in Slovenia, which was only 48% in 2020, can be increased by maintaining high quality of locally grown food for longer. Shortening of the transport chain will reduce the carbon footprint of agriculture and contribute to mitigation of climate change. To be able to do so it is necessary to increase the use of renewable energy resources where shallow geothermal energy (SGTE) is one of them. Energy-efficient cold storage solutions must be adapted to the local geological and climatic conditions and tailored to food storage requirements. Optimal planning of SGTE use enables cost-effective solutions that can reduce local food prices and the demand for food imports. To our knowledge, there are yet no solutions for cold storage of vegetables using PGTE in Slovenia or its vicinity. Therefore, our results will address these aspects and foster the energy transition of the agricultural sector.

We will identify most promising areas to develop cool storage using SGTE in Slovenia using new field measurements and numerical models at a selected pilot area. Simulations will assure optimized technological solutions with energy-, cost- and environmental-effective approaches in agriculture. All-inclusive approach will support also transfer of these new methods into neighbouring countries.
 

Project content by work packages and timeline (M=month)

1. Inventory of existing cold storage systems and analysis of their energy requirements for vegetable production, based on the results of at least one year of measurements of the operation of the selected cold storage for cabbage and/or lettuce (M 20).

2. Identification of typical baseline and peak energy demand and excess heat to be rejected to the ground in at least one pilot area, also based on a pilot cold storage site (M 22).

3. Analysis of natural settings for characterisation of the selected pilot area, also by drilling at least 150 m deep exploratory borehole and performing a thermal response test (M21).

4. Analysis of available geothermal heat pump technologies with a proposal for the selection of the most appropriate technologies in agricultural buildings according to the identified natural conditions (M 18).

5. Selection of the most appropriate quantification model for SGTE potential, accounting also for seasonal energy storage in groundwater (aquifer thermal energy storage) or in rock (borehole thermal energy storage) (M20).

6. Determination of optimal criteria for the deployment of geothermal facilities in the pilot area based on analytical and numerical simulations (M 27).

7. Preparation of draft technical guidelines and proposals for (legislative) constraints for practical implementation of SGTE, taking into account their impact on the environment. They will be prepared for the official procedure of the Ministry of Infrastructure (M 36).

8. Organization of a public workshop to discuss the draft guidelines (M 31).

All milestones No. 1 to 6 were completed by 2024. In 2025, we will prepare technical guidelines and proposals for (legislative) restrictions for the implementation of these systems in practice and present them at public workshops and in expert papers.

Financing

The total project costs are estimated to 140,000.00 EUR. The project GeoCOOL FOOD, No. V1-2213, is financed in the same shares by the Slovenian Research And Innovation Agency and the Ministry of Agriculture, Forestry and Food.

 

Members of the project group

Results

Bled, 37. tradicionalni posvet JSKS, 29. 11. 2022

ADRINEK, Simona, RMAN, Nina, PRESTOR, Joerg, JANŽA, Mitja, VIDRIH, Rajko, STEGNAR, Gašper. GeoCOOL FOOD – hladno skladiščenje hrane z rabo plitve geotermalne energije. V: ROŽIČ, Boštjan (ur.). Razprave, poročila = Treatises, reports : 26. posvetovanje slovenskih geologov = 26th Meeting of Slovenian Geologists, Ljubljana, October 2023. Ljubljana: Univerza v Ljubljani, Naravoslovnotehniška fakulteta, Oddelek za geologijo, 2023. Str. 1-5, ilustr. Geološki zbornik, 26/1. ISSN 0352-3802. [COBISS.SI-ID 178371331]

KOZOLE, Urška, HRIBAR, Gregor, RMAN, Nina, VIDRIH, Rajko. Vpliv kakovostnih primarnih surovin in naravi prijaznih pobiralnih postopkov na ohranjanje kakovosti sadja in zelenjave – predstavitev vzorcev s tipičnimi senzorično zaznanimi napakami : predavanje na usposabljanju Preprečevanje izgub zelenjave in sadja v času podnebnih sprememb in zdravstveno tveganje za ljudi pri uživanju zelenjave in sadja, Ljubljana, 22. november 2024, [organizatorja] Ministrstvo za kmetijstvo, gozdarstvo in prehrano, Kmetijsko gozdarska zbornica Slovenije [in] Biotehniška fakulteta. [COBISS.SI-ID 217524227]

RMAN, Nina, PRESTOR, Joerg, STEGNAR, Gašper, VIDRIH, Rajko. GeoCOOL FOOD – Cold food storage using shallow geothermal energy : lecture at the Geothermal DHC, Final CA18219 meetings and microconferences on storage, Limassol, Cyprus, 11-12 March 2024. [COBISS.SI-ID 189654787]

RMAN, Nina, VIDRIH, Rajko. Pomen kakovosti sadja za predelavo : predavanje na strokovnem posvetovanju v okviru 28. Pirčevih dnevov, Ljubljana, Biotehniška fakulteta, 20. 2. 2025. [COBISS.SI-ID 227097859]

ADRINEK, Simona, PRESTOR, Joerg, PESTOTNIK, Simona, RMAN, Nina. Effects of groundwater flow on end-temperature of closed-loop systems used for cooling. Renewable energy. [Print ed.]. 2026, vol. 256, [article no.] 124234, 14 str. ISSN 0960-1481. DiRROS – Digitalni repozitorij raziskovalnih organizacij Slovenije, DOI: 10.1016/j.renene.2025.124234. [COBISS.SI-ID 246318595]

Borko, K., Chapman, F.M., Raymond, J., Ryżyński, G., Rman, N. 2026: Field to laboratory assessment of subsurface thermal conductivity: A geothermal case study in Slovenia. Geothermics, Vol. 141, 103747, ISSN 0375-6505,https://doi.org/10.1016/j.geothermics.2026.103747.

 

Final project reports and other results

GeoCOOL FOOD vsebinsko poročilo

M1_1 Inventarizacija hladilnic na kmetijah (xlsx)

M1_2 Enoletne meritve v hladilnicah na kmetiji (xlsx)

M2_1 Metodologija izračuna energetskih potreb hladilnic

M2_2 Izračun energetskih potreb na podlagi monitoringa

M3_1 Metodologija za oceno potenciala

M3_2 Izvedba raziskovalne vrtine GCF-1_24

M4_1 Predlog najprimernejših tehnologij rabe PGE

M5_1 Izbor najustreznejšega modela kvantifikacije

M6_1 Primerjava obeh modelskih pristopov

M7_1 Smernice za rabo PGE v hladilnicah