A 2.5kVa inverter will draw about 100A at 24V. You therefore need a 24V 200Ah lithium (or 2x12V 200ah) battery assuming a 0.5C discharge rate. For lead acid which has a max discharge of about 0.2C, you need 24V 500Ah ie 4 x 12V 250Ah batteries. And 2,400W panels.
After searching and getting suggestions I settled with MUST ya 1.5Kva at 24,000kes. It has a 2 years warranty. Hizo suggestions elders mumenipatia hapo juu nimeona ni expensive na ni ngumu kupatikana hapo jiji.
I have 6*150 watts solar on standby. Currently I am planning to buy a 12v 300ah battery. From specs MUST 1.5kVA can support up to 60 amps charging current from solar.
If you just need a 1.5-2.5kVA to survive KPLC blackouts, the main rule is: get a Pure Sine Wave inverter so you don’t fry your TV or fridge.
A buddy of mine in Nairobi uses an SVC Energy off-grid inverter with his 5KWh lithium setup. It’s been surviving the crazy voltage drops perfectly without any issues.
Solar is a long-term investment, so don’t just buy blindly online. I know they have ready stock here in Kenya. My advice? Go physically check the units yourself and feel the build quality before spending your money. Seeing is believing. Good luck!