1000 Watts ka kuch bhee lay lo, UPS ya solar is better, generator ka masla ee rahta hay.
Solar will save you money in long run, less maintenance.
It will depend which batteries you use for UPS, AGS is good less maintenance, dry lay lo to masla ee khatam laqin dry battery is warranty ka issue hay.
Personally; if money is not an issue; I will go for solar with a bit larger backup. labmi lite jae bhee to issue nae ho ga, Even moonlight charges solar to some extent.