After advice - larger system 10kW no battery or 6.5kW system with battery

Hi everyone,
I live in Canberra Australia and have received three solar power quotes. Initially I was looking at buying a battery however one supplier advised that due to the costs of the batteries and the current poor return on investment they recommend getting a larger system 10kW which would be cheaper to install and you can sell back the additional kW to the grid.
In Canberra a single phase home (which is what I have) can only sell 5kW back to the grid.

Quotes for 6.5kW system with battery are approx. $20,000
Quotes for 10kW system no battery $10,000 - $12,000

The supplier who recommended larger system no battery advised that I could save up to $1900 per year where as with the battery it would only be $1400 noting that the pay in tariff could change (currently its around 12-13c per kW)

I am now super confused - ideally it makes sense to go the larger system without the battery and sell back what we can as the option is around $10,000 cheaper and we can always add a battery once prices drop but I’m not sure that is the best option as only one of the three suppliers recommended it to me and the pay in tariff could reduce.

Any advice is welcome.

Thanks

Hi Neale,

The correct answer is not that simple but it comes down to how much energy you actually use per day. Do you know your average daily consumption in kWh? (it will be on your bill somewhere).

Generally going for a bigger solar system is more beneficial to buying a battery as you receive extra credits for the energy sold back to the grid. If you have electric hot water you can use the excess solar to heat your hot water during the day rather than off-peak power (this basically stores energy much like a battery but as heat). See more information here… home-solar-battery-systems

Important notes: The battery capacity and inverter size required depends on the amount of ‘excess’ solar generation during the day. There is no point having a battery if you don’t have enough excess solar to charge it!
If blackouts aren’t a problem I recommend you install solar and after a year then decide if you want to add a battery. You can add an AC battery at any time in the future.

Hope this helps,
Jason

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I don’t think there is any chance a battery will pay for itself at the current price when you factor it’s price, what you can expect it to return over its life and what else you could earn with the money

I find it interesting that when it comes to all things PV, that the break-even point on the investment is a paramount consideration when contemplating to install solar panels, batteries, etc. Do people apply the same consideration when, for example, they buy that new $50,000+ SUV?, and that’s a bigger investment and depreciates in value faster and it devalues as soon as it’s driven out of the car yard!

For me, it’s a no-brainer - buy the 6.5kW system plus batteries, and say goodbye to the power company forever. Wouldn’t that be great? Keep and use all your own energy. This is what we’re planning to do in the near future, and moving to be as self-sufficient as possible. Don’t think about the Feed-in-Tariff, that to me, is a smoke screen. Think more about when you’re not paying in terms of a power bill, which will inevitably be higher than your return via the F.I.T.

my two bobs worth…
have agreat day.

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