As part of the University of Genoa’s “Energia 2020” R&D project, the so-called Smart PolyGeneration Microgrid has been developed as a pilot and research initiative to provide electricity and heat to the Savona campus.
The Savona campus is a satellite campus of the university, about 40km west of Genoa in northwestern Italy. About 6,000m2 in extent, it provides facilities for approximately 2,000 students as well as various research centres and laboratories.
Smart PolyGeneration Microgrid
The project, which was undertaken with Siemens with funding from the Italian Ministry of Education and Research, comprises a 3-phase low voltage (400V line-to-line) “intelligent” distribution system running inside the campus and connecting:
- Three CHP gas turbines with combined ratings of 160kW electrical and 284kW thermal. In the winter the thermal output is used for heating, while in the summer it is routed to an H2O/LiBr absorption chiller for cooling the student library.
- Roof-mounted PV of 80kWp
- Three CSPs equipped with Stirling engines (3kWe, 9kWth), which were installed primarily for research purposes
- NaNiCl2 storage batteries with 100kWh capacity
- Two EV charging stations (for two EVs).
The microgrid has a single point of connection to the main grid via a dedicated MV/LV transformer. It comprises a ring approximately 500m in length, with four main switchboards – for the chiller and CSP units, the storage and PV units, one of the two EV charging stations, and the second EV charging station and the CHP gas turbines.
The ICT infrastructure is a three-level hierarchical structure – at the lowest field level for data and acquisition, which feed into a SCADA system and up to the highest energy management system level.
Commissioning of the microgrid was in February 2014.
In the second phase of Energia 2020, a Smart Energy Building is under development, which will connect to the microgrid as an active load or “prosumer”. This building, which is being funded by the Italian Ministry for Environment as a sustainable building, includes a range of energy efficiency measures as well as renewable generation resources. These include a geothermal heat pump, 20kWp rooftop PV and a 3kW micro-wind turbine. Completion is due by the end of 2015.
Economic and environmental benefits
The microgrid and smart energy building are expected to lead to a reduction on the campus of about 50% in the electrical consumption from the national grid, and about 40% of the thermal consumption.
Considering the operating costs, a saving of approximately €50,000 per year is expected, while the CO2 emission reduction will be 120t per year.
These savings aren’t large when compared with the €2.4 million cost of the microgrid. However, the microgrid architecture was also based on research goals and the research team believes much larger savings would result from optimizing the generation and storage components.
Energy management and smart metering
Research opportunities opened up the Smart PolyGeneration Microgrid include experimenting with how microgrids can contribute to the provision of ancillary services in Italy and the use of smart metering for demand side management. A joint project between the University, Siemens and Enel is under way with the installation of smart meters within the microgrid for load management on the campus.