Please see my comments below:
We have just moved into a large two storey house with a pool, it has two split ACs and we are about to add two more. (I live in a similar size house with 2 X 14kW ducted units and a 165,000 L pool. We rarely use the aircon or the pool but our quarterly bill is about $1,500. We live in Brisbane. I now have a 10 kW system and it generally gets me about $250 a quarter credit). (Where do you live and what size systems do you have pool and aircon?)
We’ve just had a quote for a 13kw system with 6.5kw battery and two inverters. (Size seems reasonable. If you can afford it always go for a bigger system. The battery at this stage would not recoup your investment, the only reasons you would install a battery is either because you are a mad keen Greenie, have many blackouts at night or have a large enough system that you feed into the grid and the batteries during the day and then feed in from the battery to the grid at night (I believe this can be done but you might want to check)).
Quote was 17k and the system was not really what we had in mind in size. The company assured us it was the best option for no bills and were offering 25c on the feed in tariff. (Quote is not unreasonable but I would skip the battery at this stage. What panels and inverters are they using? Please do not go with the cheap panels or inverter for this size.)
Looking at a 6.kw with battery I can see how it works out to be efficient for a larger system cost wise but the quick calcs they based the system off was 1,700 per quarter (we haven’t received a bill yet), the old was house circa 650 with much less electrical equipment and no pool.
Does this all sound reasonable? 13kw seems over the top in my mind but we’d really like to do our bit for the environment and not have to pay ever increasing power bills!
Thanks and Best Regards
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