Been quoted around $14K for 5KW of solar and the 7KWh battery bank, hybrid inverter, etc, but that's the first place I called. That doesn't include installation and although I have a mate that is Solar Certified, you need someone who is battery certified to do that side of it apparently and there aren't too many of those people around yet - I may look into what is involved and do the course myself yet - it may be a good little sideline. :D
Mick, as for converting to Lithium later on - the chargers would be different as would the algorithms for the battery discharge cycle, so I doubt it, but upgrading that isn't beyond the realms of possibility.
Lead acid is a tried and tested technology - in a home, there are no gains to be had from the weight savings of Lithium so that negates most of the gains IMO. The batteries I'm looking at give over 2,500 cycles - the 7KWh is a true 7KWh - that is with a discharge of 60% at which point the unit cuts the batteries out of the system until they are charged again. That 2,500 cycles is before degredation starts to become a really limiting factor, but that's the best part of 7 years, which is about right.
It isn't pretty like the Tesla Powerwall, the batteries sit in an IP rated enclosure outside near the switchboard - cabinet is 1500 high, 1200 wide and 400 deep. You won't even see them where I'll put them if I go ahead - they will be behind a fence on the dead side of the house.
Still lots to think about before I jump in, but the gears are turning. :)
At those prices, payback is borderline by the time the batteries will need replacing, but that's not the only reason I'm looking at it. With the built in functionality of a UPS in the inverter, power outages become almost a non issue - the system would run the fridge, and a couple of lights almost indefinately. It will be a good test to see what you can live without should you want to go off grid - which I'll almost certainly do down the track when we move to the country later on.
The physical limitations of a suburban block will stop me doing this until I move to the country - there just isn't enough room for all the panels I'd need where I am now to tell the power companies to bugger off completely, nor have I yet curbed my electricity usage - the Spa is the biggest culprit now - costs me around $3 a day to run that sucker now - was less than $1 a day when it was first purchased.
