A rural producer near Goiania wanted relief on the pumping bill. I modelled generation, losses and payback before any module purchase, then designed the layout, protection and earthing and witnessed commissioning.
The quote on the table carried 2,310 modules and no word about the load curve. Irrigation pulled eight pumps in shifts that did not match midday sun, and the consumer unit was on the regulated A tariff with time-of-use pricing. Solar without reading the load curve is an equipment purchase, not a design.
| Stage | Criterion | Figure adopted |
|---|---|---|
| Solar resource | Site mean irradiance over a 10-year history | 5.4 kWh/m²·day |
| Array | String voltage inside inverter limits with thermal margin | 28 strings · 2 inverters |
| Losses | Row-to-row shading, temperature, cabling and dust | 13.8% per year |
| Consumption covered | Compared against 12 months of bills, no remote self-consumption | 71% of annual energy |
Commissioning recorded open-circuit voltage per string, insulation resistance, device tripping and the production curve over the first 30 days. The model pointed at 1,940 MWh a year; the first two metered cycles landed 4% below, inside the band the model itself allowed for months with above-average rain. Payback is a projection, not a contract: that is how it is written in the specification.
A plant in Guarulhos ran its 1994 substation with no discrimination and no earthing record. I redrew the single-line diagram, the me…
A 1,850 m² store in Brasilia replaced burnt luminaires like-for-like. I mapped the real illuminance of each sales zone and redesigne…
A Curitiba condominium approved 48 bays with chargers and the substation could not follow. I ran the load study with the building ma…
