From light to electric current
Panels are made up of photovoltaic cells, usually of silicon. When light strikes the cells, they generate direct current. The stronger the light, the more they produce; output falls in the evening and stops at night.
Direct current cannot power the appliances in the house directly. This is where the inverter comes in, converting it into alternating current at the voltage and frequency of the grid.
The main components
- the panels, mounted on the roof, on an outbuilding or on the ground;
- the mounting structure, which holds them in place and sets their angle;
- the inverter, which runs the system;
- the electrical protection, in dedicated distribution boards;
- the battery, optional, for storage;
- monitoring, to follow the output.
The path energy takes on an ordinary day
In the morning, as the sun rises, output increases gradually. The house first uses the energy being produced; if that is not enough, the rest comes from the grid. Towards midday, output can exceed consumption, and the surplus can charge a battery or go to the grid. In the evening, the house draws on the battery, if there is one, or on the grid.
Three types of system
Grid-tied (on-grid)
No battery. It is simple and suited to daytime consumption. When the grid goes down, the inverter switches off.
Hybrid
Adds a battery and, in certain configurations, a backup function. Details on hybrid solar systems.
Stand-alone (off-grid)
It is not connected to the grid and depends on batteries and, sometimes, a generator. It calls for very careful sizing and involves higher costs.
What comes next
If you want to see what would suit your home, start with photovoltaic panels and the indicative calculation. For a conversation about your own case, request a quote. We work in Bacău County, in Bucharest, in Ilfov and in Suceava County.