Developing and Promoting Microgrids in Rural and Island Areas

Microgrids precisely propose to address these objectives on low-voltage networks by controlling and optimizing the operation of local systems, composed of loads, energy sources and eventual storages.

Microgrids are generally defined inside a delimited perimeter; they can be connected to the main grid or offer solutions to operate “off-grid”. Different types of microgrids start to be distinguished according to the different issues they try to face, but also according to the market segment they concern: industrial microgrids, campus microgrids, island or isolated microgrids, military microgrids, village community microgrids.

Microgrids interact with many stakeholders. They have to offer them optimal solutions from the energy management point of view but they also have to take into account economical aspects and give orientations to economic decisions such as buying or selling electricity on the wholesale market. Sometimes the political dimension and the need to assure the security of supply also become the main driver.

In the PEGASUS project, 10 partners from MED countries are working together to study into more details microgrids, focusing on rural and island areas. The objective is to implement a set of tools and measures that aim at facilitating the development of microgrids. PEGASUS partners are coming from various structures: municipalities, energy agencies, universities, private companies. Seven partners have to work out specific simulations on pilot sites, so that the results of PEGASUS will rely on ground – based data. The project also includes an important module on the transfer of the results and plans to associate closely local and regional authorities so that they can use the proposed measures to introduce dedicated support to microgrids in their respective policies.

Since the beginning of the project, one year ago, most of the work has been focused on the selection of pilot sites, the installation of measurement devices and the launching of first simulations. The seven pilot sites are very different and can be spread into the following categories: village community microgrid (2), building-scale microgrid (3), university microgrid (1), medium-voltage microgrid (1). Greek and French microgrids are both focusing on a village community, and base their simulation of the microgrid on numerous data, mainly monitored from residential households.

• In France the pilot site is located in the center of a small mountain village, Saint-Julien-en-Quint. It gathers the 40 consumers connected to the central low voltage substation. Most of them are residential users, but there are also a few agricultural buildings as well as public premises.
• In Mega Evvidrio (Greece) the site is even bigger and measures will be registered on 62 buildings, 55 of them are residential (among the 171 permanently inhabited houses of the community) and the rest represents public offices. The pilot site also includes several PV plants, among which 5 existing PV parks of 100 kWp each, 5 PV existing PV systems on roofs and 75 autonomous systems to be installed on the roofs of houses.
• In Cyprus, the aim is to a controlled research hub with a microgrid architecture within the University of Cyprus (which makes it rather a nanogrid than a microgrid). It consists of controllable and uncontrollable loads of the FOSS lab, an electric vehicle charging station, PV systems and storage equipment.
• The Potenza pilot site (Italy), quite different from the previous ones, aimed at demonstrating the achievable advantages (primary energy, peak shaving, reduction of energy bills) by the Municipality in two different sites: a swimming pool, where a 165 kW CHP is able to provide about 95% and 85% % of the required thermal energy and electricity, respectively, and also to feed, through the existing distribution network, about 70% of the electricity consumed by an electric escalator, having an installed power of 192 kW, used to transport people from the outskirts to the city center.
• In Malta, the pilot site is located in Gozo island and consists of 10 public and private buildings, having both consumers and prosumers profiles. The objective is to simulate a microgrid operation, including storage systems and flexible electricity tariffs.
• In the Sport Park Ruse (Slovenia), the pilot site is based in a sports resort and includes two existing PV plants of 100 kWp each. The objective is to make the best use of the PV resource, eventually including storage systems, so as to provide cheaper electricity tariffs to end-users.
• In the Dalmatian Municipality of Preko (Croatia), the microgrid is composed of 5 consumers and 1 prosumer with the involvement of the Local Public Authority. The aim is also to provide cheaper electricity for the neighboring consumers.

For all these pilot sites, the monitoring started at the end of 2017 / beginning of 2018 and will last one year. The economic and technical feasibility studies will integrate these real data to develop a microgrid model and identify the conditions of reproducibility.

Several questions are still open:

• Which governance should be applied? Who should lead the process?
• Which cost categorization and how to deal with the upfront investment?
• What are the conditions for profitability?

Pegasus aims at providing some first answers to these questions.