Page 9 - Water-energy_2020

F. Calise, et al. Energy Conversion and Management 220 (2020) 113043

Table 1
District simulation data: Santa Maria di Salina and Favignana.
Geometric features Both districts Santa Maria di Salina Favignana

V1 V2 H-SMS Sch-SMS Off-SMS H-F Sch-F Off-F
2
Height (m ) 3 6 6 6 6 6 6 6
3
Volume (m ) 280 559 1080 2655 1080 1209 5208 3750
2
Floor area (m ) 93.24 93.24 180 442.5 180 201.45 868 625
Number of planes (−) 1 2 2 2 2 2 2 2
Number of apartments for floor (−) 1 2 –
2
Apartment area (m ) 93.24 93.24 –
2
Glass area (m ) 19.15 38.73 51.11 72.90 64.84 45.08 171.80 66.72
st
Heating and cooling season (Salina 669 HDD) Heating: T set = 20 °C 15th November-31 March
Cooling: T set = 26 °C 1st May to 30th September
Heating and cooling season (Favignana 686 HDD) Heating: T set = 20 °C 15th October-15th April
Cooling: T set = 26 °C 1st June to 15th September
Thermal Energy demand Figs. 4 and 5
Air infiltration rate (vol/h) 0.6
3
Average daily DHW demand (m /day/person) 50
DHW set point temperature (°C) 45
Tyrrhenian Sea in South Italy. Favignana is modelled according to the drinkable freshwater. The MED system is driven with thermal energy
same approach used for Santa Maria di Salina. In particular, the same from the CPVT collectors (Table 4). In particular, the district heating
representative types building are considered. Note that office, hotel and network directly uses the thermal energy provided by the CPVT col-
school buildings are featured by different geometrical features with lectors. Moreover, biomass heaters are installed as auxiliary systems, in
respect to the ones considered in Salina (Table 1). Regarding the order to match the thermal energy demand when the solar radiation is
thermophysical proprieties of the buildings, no remarkable differences scarce or null. The district cooling network is supplied by an absorption
are assumed between the two locations. Since Favignana is a very at- chiller driven by thermal energy produced by the CPVT collectors. An
tractive touristic place, a significant increase of the number of in- auxiliary electric chiller is also installed for matching the cooling en-
habitants is considered during the summer season, as for the case of ergy demand when the thermal energy produced by the CPVT collectors
Salina. In particular, the inhabitants of the island increase from 965 in is not sufficient for the activation of the absorption chiller. Another
winter to 2000 in summer. Table 3 displays the number of buildings district heating network provides the thermal energy for DHW pre-
occupied during the year. For the evaluation of the thermal energy paration, using thermal energy from the CPVT field. A biomass aux-
demand of Favignana and Santa Maria di Salina, the heating and iliary heater is installed for meeting the thermal energy demand for
cooling seasons are assumed according to Italian regulation: Heating DHW preparation, when the thermal energy supplied by the CPVT is
st
season from 15th November to 31 March and cooling season from 1st insufficient. Finally, the power demand, including the power delivered
May to 30th September. to electric components of the plant, electric chiller and district demand,
Proposed system PS1: CPVT-ACH-MED is referred to Favignana. This is matched by power produced by the CPVT collectors. When the CPVT
polygeneration plant includes a CPVT field that supplies a district power production does not meet the district power demand, a suitable
heating and cooling network and MED technology that produces amount of power is withdrawn from the local grid. Conversely, the

Fig. 3. An example of the SketchUp 3D model:

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