Photovoltaic sizing: consumption, roof, irradiation and payback (with the site's sizing tool)

In SO1 you learned to check a kWp figure. Here you learn to arrive at it yourself and to defend every number in writing. You read 12 electricity bills and pull out the average, the seasonality, the custo de disponibilidade (the minimum billed consumption) and the effective tariff. You look up your city's irradiation in the Brazilian Atlas of Solar Energy and in SunData. You understand where each loss in the 0.75 production factor comes from. You turn kWp into 550 to 600 W modules and microinverters, checking the DC/AC ratio, voltage and current of each input. You assess the roof's area, orientation, tilt and shading. You build the month-by-month generation, calculate the savings with the Fio B of Law 14,300 and the payback in scenarios, without promising a return. You use the site's sizing tool knowing what it cannot see, and you close everything in a calculation record and a one-page proposal. The common thread is a small grocery store using 1,100 kWh/month and the 450 kWh/month house from SO1. The course covers pre-sizing and quoting: detailed design, structural design, the professional's technical responsibility record (ART) and utility approval are out of scope.