Associate
Have solar installed in far north Queensland, Australia. We get pretty good rebates on rooftop solar. Had a 13.2KW system installed recently at a cost of $9000 (approx) £5000 after rebate. On a clear day the system generates 55-59KW, cloudy/rainy 7KW. House of 4 generally using 20-25KW per day, in summer with air conditioning rising to average 35KW. Battery doesn't make any economic sense here, payback outside of 10 year warranty, fit is 7.8c (approx 4p) per KW. Power cost 29c (16p). I guestimate payback within 5 years, maybe less...we have our hot water system on a day timer so divert excess power to that. Most people go with 6.6KW systems but as we have 2 phase power this was made good economic sense.