3. Why using the Photovoltaic system? Is it energetically profitable? Is it environmentally profitable? Is it economically profitable?
4. Is it energetically profitable? YES, IT IS! To build a 1 kWp photovoltaic system (panels, supporting structure, cables, inverter, etc) 2500 kWh are necessary; then it will produce 1350 kWh/year in Taranto, thus obtaining: Energy payback period of the energy investment: 1.9 year (N.1); this is a heavy burden on the environment and it is acceptable for a period of 25-30 years. This kind of plant is second only to last generation eolic generators, which programs a payback period of the energy investment of about half of the photovoltaic system, that is : 8 months for a period of 20 years….. if the wind blows!!! Notes N.1 = Plant installed on roof, including a single crystalline photovoltaic panel with a 14% output.
5. Is it energetically profitable? YES, IT IS ! To assess the environmental impact of a photovoltaic plant the following data are used: LCA, Life Cycle Assessment which considers 1) Energy used, 2) Raw materials used (silicon, copper, water used) 3) Environmental Emissions (contribution to the greenhouse effect, production of dangerous waste, consumption of the stratospheric ozone, etc) during its complete life cycle, from the extraction of the necessary raw materials up to the waste disposal and/or the final recycling.
6.
7. The emissions in the air of Carbon Dioxide in the complete life cycle of the Photovoltaic system are equals to 30-40 g/kWh of peak power, that is 22 times inferior to a Coal plant, 9 times inferior to a gas plant, comparable to those of a biogas plant, 4 times superior to an eolic plant, 10 times superior to a nuclear power station. For the end-of-life recycle (raw materials used again to rebuild new panels) about 90 kWh/m2 are necessary: 33.500 tons of modules to dispose within the year 2040 are expected. The photovoltaic environmental impact turns out to be 10 times inferior, if compared to the present Italian energy mix (mainly obtained by Gas, Oil, Coal)
13. CHARACTERISTICS OF THE SITE ( RESEARCH ON SPOT) Roofing = FLAT Available surface on the roofing = 2000 m2; Presence of Faraday shield = yes Height of perimetric parapets = 90 – 105 cm Presence of shading obstacles = None View of the Southern side and of the exit from the staircase
18. Investigation on site with pilot pane l Gymnasium Staircase Entrance South ROOFING MAP 1= Central heating area 2= Gas storing area
19. SHADING ASSESSMENT – panels completely turned to the South First row panels maximum sun height Second row winter solstice Panel length School covering IT IS POSSIBLE TO IMPLANT 3 ROWS OF PANELS ON THE SOUTHERN PART. THIS IS THE IDEAL SITE.
20.
21. POTENTIAL DIMENSIONS OF THE PHOTOVOLTAIC PLANT POWER OF A SINGLE PANEL = 180 W peak power NUMBER OF PANELS = 110 (maximum) PEAK POWER = 110 x 180 = 19,8 kW peak (maximum) SIMULATION OF THE SETTING UP OF 110 of 180 Watt photovoltaic panels.