- SOFTWARE:
- FLAC3D
- Rhinoceros3D
- RS2
+358 50 560 6893
Rock mechanics simulations of the excavation and 50 years of operation of a seasonal heat storage facility
Vantaan Energia Oy is building Varanto, a seasonal thermal energy storage facility located in Vantaa, Southern Finland. The seasonal thermal energy storage stores energy in hot water in three underground caverns and the stored heat may be used to heat buildings via the district heating network when necessary. The caverns are 20 m x 300 m x 40 m in size and will be excavated with the lowest excavation level being 100 m below ground level. The caverns filled with hot water will be pressurized allowing the water to reach temperatures of up to 140°C without boiling or evaporation. The total thermal capacity of the fully charged seasonal thermal energy storage is 90 GWh and is equivalent to as much as 8 million euros worth of district heating.
Rock mechanics simulations were performed to support the preliminary design of the facility. Several variants of shape, size, location and layout of the caverns were studied to evaluate underground stability and the safety of the facility and to optimize construction costs. The behaviour of the bedrock, fractures and weakness zones surrounding the facility was simulated during excavation of the facility and an operation time of 50 years. Several simulation variants were run with variable cyclic thermal loading/unloading sequences and different maximum temperatures to find possible solutions for the design and concept. The performance of the variants was evaluated in terms of stress and displacement evolution, deformation of rock mass, fracture and weakness zone opening and closure, as well as possible shear of the zones. With the joint efforts of process design and the design of underground spaces, the project was able to reach economic feasibility and proceed to the execution phase of the facility in 2024.
Cookie | Duration | Description |
---|---|---|
cookielawinfo-checbox-analytics | 11 months | This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics". |
cookielawinfo-checbox-analytics | 11 months | This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics". |
cookielawinfo-checbox-functional | 11 months | The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". |
cookielawinfo-checbox-others | 11 months | This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other. |
cookielawinfo-checbox-others | 11 months | This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other. |
cookielawinfo-checkbox-necessary | 11 months | This cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary". |
cookielawinfo-checkbox-performance | 11 months | This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance". |
cookielawinfo-checkbox-performance | 11 months | This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance". |
viewed_cookie_policy | 11 months | The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data. |