Several pilot configurations will help develop ALPGRIDS outputs, among which the Alpine Microgrid Model. The Model will provide guidance and concrete tools for target groups in order to facilitate the development and implementation of new projects addressing local territorial goals. The model will address topics such as governance, regulation, financing, available technical solutions and market players.
City of Savona (Italy)
The pilot project, managed by IRE and supported by UNIGE, focuses on the development of a feasibility study of a microgrid in a neighborhood of the city of Savona in the north-western part of Italy.
The idea is to expand the microgrid architecture already existing inside the nearby Savona University Campus (University of Genoa) to a city district with the third aim of testing the application of sustainable power systems in the framework of a local energy community, decreasing the energy bills of users and improving the local resilience against blackout. Today, the area includes a public football field, a small public park and a swimming pool, but this project also incorporates the realisation of 3 buildings to host private companies and social housing.
The planned microgrid will consider different energy vectors:
- electricity, locally produced by PV plants;
- thermal energy, supplied by traditional heat pumps, geothermal heat pumps, solar collectors and electric boilers;
- cooling energy, produced by traditional heat pumps and geothermal heat pumps.
Moreover, electric storage batteries and thermal storage systems are also considered in order to maximise the use of renewable energy. Two different control levels will be applied:
- at higher level, the Energy Management System (EMS) of the microgrid will optimally operate and control the microgrid through a centralised approach;
- at lower level, Building Energy Management Systems (BEMSs) will operate optimally and control each building. There will be a bidirectional communication between EMS and each BEMS.
WEIZ Campus and Municipality of Thannhausen (Austria)
The focus of WEIZ pilots is the exchange of electricity within a neighborhood of different consumers.
For the first pilot, the WEIZ Campus, it is the goal to implement an intelligent Energy Management System for the direct connection between WEIZ I and WEIZ II as well as to implement an energy storage with a capacity of about 200 kWh. The W.E.I.Z. II electricity is generated by the installed PV system and is primarily used for general electricity in the W.E.I.Z. II. The excess electricity is either used to charge the battery storage in the building or, as soon as it is fully charged, transferred via a direct electricity connection to the neighboring building W.E.I.Z. I. The second pilot is the direct connection between the PV plant of the Municipality of Thannhausen with their neighborhood.
The project results will be (1) a functional demonstrator for a shared use of PV generation via point-to-point connections, (2) simulation models for dimensioning the system’s components, (3) a validated measurement and control system, (4) business models and clearing system considering the needs of users and providers as well as insight on the economic feasibility of the approach, (5) insights on the reproducibility of the approach and finally (6) a technology-service-tender for shared use of local PV-generation via point-to-point connections.
Val de Quint valley (France)
The “Val de Quint” valley is a rural area of about 760 inhabitants. Mostly a residential area, it is also concerned by agricultural and touristic activities and a few very small enterprises. Saint-Julien-en-Quint, one of the 6 villages located in the Val de Quint valley, is already involved in microgrid activities, with shared PV selfconsumption. This village will form a first pilot site considering realised data and existing energy facilities. As the local stakeholders aim at extending the microgrids activities to the entire Val de Quint area, this will form an extended pilot site relying on simulated data, allowing us to consider various microgrid configurations, including energy storage options and cogeneration of heat and electricity. On both sites, the studies will mainly focus on economic issues related to the energy consumption flexibility provided by the microgrids.
Municipality of Selnica ob Dravi (Slovenia)
The pilot project focuses on the development of a feasibility study of a microgrid of public buildings in the centre of Selnica ob Dravi. Different pilot development steps and activities were split up and will be implemented between two partners, the Municipality of Selnica ob Dravi and Energap.
The aim of the project is to establish a pilot microgrid that serves for modelling and finding solutions for:
- possible self-sufficiency of public buildings and thus reduction of energy costs;
- possible island operation of the microgrid, which would provide energy even at a failure of the public network in the event of natural and other disasters;
- legal formal establishment of an energy community, in which, in addition to the municipality, interested citizens would also participate and would finance the installation of photovoltaic power plants.
When the community is established it will involve the following public sector stakeholders – municipality, school, kindergarten, cultural centre and fire station. The school will serve as a production unit and a user. If possible, the fire station will have a production and a small storage system; others will be users.
Through the pilot, the technical and legal aspect of setting the community will be studied. The pilot will act as a showcase for citizens to see and understand the microgrids. Through measuring the production and use and using the system of net-metering, we will try to produce as much of our own energy as possible. The energy efficiency measures on the user’s site will be also implemented to achieve as much self-sufficiency as possible.
City of Udine (Italy)
he pilot project aims to apply the recent Italian regulation on renewable energy communities to three public buildings, a school, a kindergarten and a museum, and four social housing buildings, all organised in a microgrid.
High-efficiency CHPs, in a partial replacement of the existing gas-fuelled boilers, are envisaged at the school and the kindergarten, with the related benefits of a reduction in primary energy consumption, carbon emissions and overall energy bill of the Municipality.
The electricity generated by the existing PV plants and by the CHPs will be shared into the microgrid, contributing to its greater energy self-sufficiency. It will verify the convenience of a complete entry into the network of the electricity coming from renewable sources, as provided for by the new regulation on energy communities, compared to a real local consumption.
For the purpose of optimal sizing and operation of CHPs, an annual campaign for continuous monitoring of heat and energy exchanges, as well as the generations of PV systems, will be carried out on the buildings involved. The processing through a simulation model of the acquired data will define the most effective configuration of the local energy community in terms of energy and economics.
Pilot site in the City of Grafing (Germany)
Grafing is a city in a semi-rural environment 30km east of Munich. With around 13,600 inhabitants and around 6,100 grid connection points, Grafing has a total yearly consumption of electric energy of approximately 24GWh. Out of this, 10GWh is produced locally. This results in a self-sufficiency rate at city level of around 40%. In Grafing, the increasing number of EV will sooner or later provide challenges for the electric grid.
A retirement home will be built in the center of Grafing for 43 residents. The start of building is scheduled for 2022. This is an opportunity to explore a Microgrid solution, where a photovoltaic power plan on the roof of the building supplies the 43 appartements of the residents using the Mieterstrom model. It is planned to install electric vehicle charging in the (partial public) underground car park below the retirement home. To increase self-sufficiency and use of renewable energy, the effect of storage and EV charging are analysed. Legal issues and boundaries of the Mieterstrom are explored. Existing local data of solar supply and EV charging will be used to set up a simulation model and discover different scenarios and their effect on economics. A metering scheme that allows for correct billing of local produced energy and energy from the grid has to be set up.
Originally planned microgrid solutions, where using the public grid to enable energy sharing between different buildings would be necessary, are hindered by German legislation, as the EU rules of Clean Energy Package have not been implemented.
Pilot sites followed by AURA-EE (France)
AURA-EE has chosen to work on several pilot sites in the Drôme department for all of which a collective self-consumption scheme will be set up. Collective self-consumption means that a local PV producer can sell its electricity directly to local consumers. Previous studies have shown that business models of collective self-consumption are difficult to implement in France, and that their profitability is highly dependent on the load profile of the consumers involved. By working on a wide range of situations, AURA-EE hopes to identify the best conditions under which such projects can be implemented, so as to help municipalities and energy communities develop more easily their future projects.
The six pilot sites (Saint Marcel-les-Valence, La Roche-de-Glun, Die, Montélier, La Chapelle-en-Vercors, Eurre) have been selected thanks to a call for interest sent to all the municipalities of the Drôme department. They are mainly small villages, either in rural or semi-rural areas. On all these sites, potential PV projects are already identified, some energy communities sometimes already exist and all the buildings are equipped with smart meters, which makes it easier to collect some data.
The project starts with the collection of the load curves of each building during one year. Overall, about 50 buildings are concerned. These load curves, that is the average power over short time intervals as a function of time, will be provided by the existing smart-meters at a 10- or 30-minute timestep (depending on the power subscription). Then, we plan to simulate the PV production curve at a 30-minute timestep on the basis of meteorological and satellite data. The power of the PV plant will be adjusted to the building perimeter so as to reach a high self-consumption rate (> 90%).
Various scenarios will be designed according to building perimeter (ultimately, we might only keep the buildings whose load curve best suits the PV production periods), the PV capacity and different financial schemes.
At the end, the data analysis will assess, on each pilot site and for each consumer, what share of local production can be self-consumed and when. Then, adding the financial hypothesis, the aim will be to find out the best PV electricity price structure, fitting both the producer and the consumers so that we get a well-balanced model over time.