Work out the solar system size, panel count, inverter rating and battery bank you need — from your average electricity usage and desired loadshedding backup.
Assumes a 75% system efficiency (panel + inverter + wiring losses) and an 80% usable depth-of-discharge for a lithium battery bank — both standard planning figures, not manufacturer-specific. Get a site survey for a final, install-ready quote.
A panel rated 1kW under lab conditions rarely delivers a full 1kW of real, usable energy per peak sun hour once you account for panel efficiency loss in heat, inverter conversion losses, and wiring/dust losses. A 75% overall system efficiency factor is the standard planning assumption used across the industry to size a system that will actually cover your real usage, not just its nameplate rating.
The solar panel array is sized to your total monthly consumption (so your bill drops). The battery bank is sized separately, only to your essential backup load and how many loadshedding hours you want covered — running the whole house on battery for hours is usually neither necessary nor affordable, so most homes back up just lights, fans, routers and a few sockets.
A grid-tied (on-grid) system needs no battery and is cheapest, but shuts off during loadshedding for safety (anti-islanding) unless it's specifically a hybrid inverter. A hybrid system adds batteries so it can supply your essential loads when the grid is down. Fully off-grid systems (no grid connection at all) need a much larger battery bank sized to multiple days of full usage — rare for a normal home.