DEMAND/SUPPLY MATCHING

3. MATCHING DEMAND/SUPPLY FOR CATANIA

Fig.5 Hydrogen production & utilisation over a year 

Fig.6 Demand & supply during a winter week

Fig.7 Demand & supply during a spring week

Fig.8 Demand & supply during  a summer week

In Catania, 56 PV panels are required to power the electric load of the dwelling, with an energy demand valued at 80% of the standard UK demand. The volume of hydrogen stored for seasonal storage (positive area) or used to cover the deficit of demand (negative area) for different months of the year is shown in Fig.5. During spring and summer time 23.6 cubic meters of hydrogen is produced in excess by the system and is stored for use during the winter. 2 cubic meters of hydrogen remains unused during this period. The system is obviously not self-sufficient during wintertime and the hydrogen stored during summertime is required to power the fuel cell supply during the winter.

The system requires to use 5.2 cubic meters of hydrogen stored during the summer months to power the fuel cell during January. The PV panels produce 120 kWh stored as 2.8 cubic meters of hydrogen, and 220 kWh of the electrical demand must be supplied by 9 cubic meters of hydrogen via the fuel cell.

The system is self-sufficient during the spring and summer months, and excess energy can be stored in the form of hydrogen. The system can generate an excess of 3.7 cubic meters of hydrogen during April and 4.6 cubic meters of hydrogen during August for use during the winter months. The 56 PV panels required to power the dwelling have an area of 37 square meters and the fuel cell is rated at 2 kW to power the electrical load of the dwelling.