Work Package 5: Pilot & Demonstration Projects

The deep geothermal underground laboratory (DUG Lab) project aims at a better understanding of hydro-seismo-mechanical coupled processes that are associated with high pressure fluid injections in a crystalline rock mass. Experiments are carried out at laboratory scale (a few centimeters) and at intermediate scale (a few tens of meters).
Currently, medium-scale experiments are carried out at the Grimsel Test Site. The project is divided into three main phases, namely a characterization phase, a stimulation phase and a circulation phase. The characterization phase includes geophysical and geological imaging of faults and fractures, and determination of the actual stress field by means of small hydro-fracturing experiments. During the stimulation phase, fault zone will be pressurized until slip occurs, and the associated permeability creation, pore pressure propagation, deformations and seismicity will be monitored. In a second step of the stimulation phase the massive rock mass between the faults will be hydro-fractured, which allows the circulation experiments to be conducted. The characterization phase could be completed in 2015, and it is expected that the stimulation experiments will be finished by the end of 2016. The entire medium-scale experiment will be finished by the end of 2017. On the basis of the results, the following large-scale experiment will be established.
The total budget of the experiment is in the order of 6.5 Mio CHF, whereby 1.8 Mio CHF were contributed by Shell donation to ETHZ and a grant by EKZ. The remaining costs are covered through the SCCER-SoE, ETHZ and UniNe.

GeoEnergie Suisse AG is developing a pilot and demonstration project for deep geothermal energy in the village of Haute-Sorne (Jura). Planned is a petrothermal deep geothermal project reaching down to 4000 – 5000 m. The system is projected to deliver up to 5 MWe and/or heat for industrial processes as well as district heating. The total project costs are roughly 100 Mio CHF. For the first time, the project will implement the so-called multi-fracture system in a granitic environment. Drilling is scheduled to start in 2017 or 2018.
The SCCER-SoE has already in Phase I collaborated closely with GeoEnergie Suisse AG (GES). The Haute-Sorne type project is a cornerstone of the deep geothermal energy roadmap of the SCCER-SoE and SCCER-SoE scientists played an important role in advancing the project, for example by developing strategies for assessing and mitigating seismic risk, for optimizing the reservoir design and monitoring strategies. The Haute-Sorne Project is also a demonstration site in the EU Horizon2020 funded project DESTRESS (2016 – 2020), where ETH Zurich and GES have together a budget of about 7 Mio Euro.
In Phase II, these links will become even more critical: Enabling the success of the Haute-Sorne project is one of the highest priorities of the deep geothermal energy activities of the SCCER-SoE. Many SCCER-SoE activities will be targeted towards enabling the technology but also in using the data from Haute-Sorne for calibration, upscaling and validation of methods and results, such as strategies for adaptive traffic light seismic monitoring systems, underground heat exchanger design, construction, and optimization, as well as research on optimal fluid circulation and associated heat extraction strategies.

This demonstration project will be implemented as part of the “GEothermie-2020” program of the Canton of Geneva. A step-wise approach including drilling wells (production and storage) at progressively increasing depths (1500-2500 m) will be performed by SIG during Phase II (Q4 2016 – 2017). This will provide the opportunity to test and validate the effectiveness of exploration concepts and models developed within WP1 as well as proof the feasibility of direct heat production and subsurface storage potential in sedimentary basins at relatively shallow depths. The project is already approved and in advanced stage of realization.

According to IEA, IPCC and COP21, CCS has to be implemented to keep global warming within 2°C. After a long phase of experimentation on capture and sequestration technologies, efforts in Europe to implement a concrete strategy are growing, under the umbrella of the ECCSEL ESFRI infrastructure and the newly approved ERA-NET Cofund ACT. The Swiss plan is being developed by SCCER-SoE groups together with SFOE, BAFU and industry participation (on-going discussions with three possible industry partners). The plan aims (i) to use the ERANET-ACT support to expand the work already carried out in SCCER-SoE Phase I and previous national projects (CARMA) to ensure that the required science and technologies are available, and (ii) to realize a first pilot project in Switzerland to demonstrate at the field scale that CO2 storage can safely be done without causing unacceptable seismicity, fluid-mineral reactions and environmental contamination. The timescale of ERA-NET Cofund ACT is very favorable, with expectation of funding by 2017 (Swiss quota of 4 MFr for 4 years). We aim at initiating with SFOE a CO2 sequestration pilot by 2019.

A new small HP plant that will be installed/built in the coming 2 to 3 years will be selected to provide a comprehensive set of research carried out by SCCER SoE partners (and if possible SCCER Furies and SCCER Crest). Thanks to a concurrent approach, this demontrator will show the ability of a small hydropower station to produce clean, sustainable and renewable energy while producing ancillary services. Using the results from WP2 and WP3, several topics will be addressed such as: the now-casting and seasonal forecasts of discharge to the water intake as a basis for sediment management and for a flexible power production scheme; a critical review of the implemented operation practice, in view of efficiency improvements considering multi-sectorial objectives; a technical optimisation of the hydro electrical equipment operating conditions allowing a flexible control and set up of a predictive maintenance; investigation of the ecosystem functioning (metabolism, food web), fish migration and biodiversity; assessment of the new regulation for small hydropower plant and the possible financial models.

Following the preliminary implementation carried out in the Mauvoisin reservoir in Valais, we will implement a project with HP industry with the goal of demonstrating the effectiveness of technologies to artificially stir the water stored in a dam reservoir to prevent sediment from settling and allow for the sediment to be conveyed downstream at acceptable rates through the turbines. The mobile mixing devise (demonstrator) will be tested at several dams (1 to 3) to show its efficiency in different conditions.
Expected outcome from real-size field demonstrator will be to: validate flushing efficiency (per m3 of water release, per kWh of energy forced into the reservoir) as  compared to laboratory development conditions; characterize dependence from local conditions (reservoir morphology, arrangement of reservoir inlets & outlets); identify practical difficulties and shortcomings of field implementation and deployment; control the modifications to the sediment regime in the river downstream of the powerhouse as well as in the residual flow streth, and the resulting environmental impacts. We will seek funding for industry and SFOE to initiate the demonstrator in 2017.

FLEXSTOR will test a set of innovative tools for flexible operation of storage hydropower plants in changing environment and market conditions at a complex hydropower scheme. This demostrator is motivated by the main hydropower challenge in Switzerland, namely the need for flexible operation targeting premium remuneration hours, for which comprehensive methodologies for hydropower upgrading projects are still missing.
Specific goals of FLEXSTOR are to demonstrate how to: concentrate production in less hours, while mitigating negative impacts (e.g. river up/down surges); manage reservoir sedimentation to expand storage capacity while complying with the Waters Protection Act; address mountain slope instability risks in periglacial zone, avoiding non-optimal “preventive reservoir lowering”; identify the changing demand structure and the required adaptation of the  storage management; extend the operating range of hydraulic machinery, whilst avoiding instabilities; optimally manage a compensation basin in order to minimize the ecological impacts of hydropeaking in the downstream river reach.
All these developments, which are at the core of the WP2 efforts, will be validated with proof-of-concept in the complex system of KWO Oberhasli, which allows later replication to other hydropwer schemes in Switzerland. The demonstration project has now been approved by CTI and industry (1'360kCHF) and will last till end 2018.