The right solar backup size comes from three questions: which appliances must stay on during a power cut, for how many hours, and how much sun your roof receives. Answer those and the inverter, battery and panel sizes follow.
Which loads should a backup cover?
List the essentials: lights, sockets for phones and laptops, the Wi-Fi router, the TV, the fridge, the gate motor, CCTV and the electric fence. Heavy loads such as electric cookers, water heaters, irons and pumps need much larger systems and are often left on the grid or a generator.
How do you size the inverter?
The inverter must handle everything that runs at the same time, plus the surge when motors such as fridges and gate motors start. Adding the wattage of the loads that run together gives the starting point.
How do you size the batteries?
Multiply the power of the essential loads by the hours you want to cover. A home that wants lights, the router, the TV and security on through an evening outage needs far less storage than one that wants the fridge running overnight. Lithium batteries can use more of their stored energy than lead acid ones, so the same need is met with a smaller bank.
How do you size the panels?
The panels must recharge the batteries and run daytime loads using the sun available on your roof. Kenya gets good sun in most places, but shade, roof direction and the season all count.
Can I start small and grow?
Yes, if the inverter and batteries are chosen with room to expand.
Our survey measures your loads and roof and gives you a written design. See solar and power backup, solar in Nairobi and Machakos, or the areas we serve.
