This was a 22kW solar system. REC panels with SolarEdge inverters, paired with 2 Tesla Powerwalls.

I love that! Taking charge! Enjoy the freedom of knowing you've got it under control!

ROI is important - but it is not the only factor! I've seen customers with evening power prices as high as 66c/kWh whereas I'm paying 31c. So for many, prices have doubled already. The higher power prices go, the better the ROI for batteries become.

A $15k battery will be warrantied for 10 years (or more), the return would have to be ~$1500 a year, or $120 a month, $4 a day. Your bills would have to be reduced by either the FIT changing, or the Tariff changing. $4/day isn't always obvious, especially because Tariff pricing going up, doesn't seem to be factored into the ROI. Neither does FIT dropping to 4c or lower. A lot of these calculators are based squarely on $/Kw of storage, not looking at the use cases or the ways that billing could change, and is changing in the future. Keep in mind, 10 years, the battery keeps working, but the available storage gradually depreciates from 13kw to 8-9kw. By then, you have 2033 Solar/Battery technology and 2033 inflation/pricing of electricity. The predictable ROI isn't really going to deliver $100 each month, unless there's a cause to use that much power, e.g. Air Conditioning or EV charging, or a Pool Cleaning pump or other daily use. To break even, the battery would likely require that 13kw of storage to pay for peak usage (38c to 98c), or to cover the gap between tariff and FIT. i.e. 13kw of 4c to 15c FIT "lost" vs 13kw of 38-98c Peak traded. At a 65c peak, that's $8.45 per day, from 5pm to 9pm or 2pm to 8pm. That's a kettle, a microwave, oven, AC, TV, room fans, computers, Saving 10-12kw over 4 hours, there's your $4-$5/day. That's also if there's no other incentives/discounts or VPP type events, negative price events, solar soak events, etc. A lot of the money is just made from Grid Stabilisation, i.e. soaking up excess solar from the grid, and exporting it during peak periods, i.e. SmartShift and that's handled by the VPP or APIs in the batteries now. I have no idea if this is sustainable for a whole decade, but I have a feeling that it will be ... because tariff changes happened when they removed 2 powerstations from NSW. YMMV If the battery saves you 10kw of peak power during high demand or high peak, it's probably going to make the money back fairly quickly that you would have spent. Especially when it comes to Demand pricing and occasional spike use, i.e. cooking dinner, using the microwave, the fridge comes on, while the hot water and AC are on, etc. Now you have a demand surge for the month that might push $10/day in costs, and you never noticed. Most of these ROI calculators made assumptions about grid pricing being in the 30c/10c FIT or 20c/12c FIT. That arbitrage of Peak vs FIT, Load shifting. If you're in Sydney/Ausgrid, that would have changed recently from ~25c to ~38c/kWh in less than a year. And FIT would have gone from 12c-15c/kWh to 4c-6c/kWh. YMMV. There's also trials of EA025 (Residential ToU) and EA111/115/116 (Residential Demand TOU/Residential Demand rates - where your peak usage affects the entire month's bills), which is running alongside the Ausgrid's Solar Soak / Twin Rate EA959 and EA960 rates, which basically only give you FIT between 2pm and 8pm when peak rates are highest. These Solar Soak plans tend to work well if you can avoid high usage, but occasionally these Solar Soak plans have Negative Price events, so exports cost money at these times. What does this mean for payback periods ? If your metering changes, and it seems like Ausgrid will start to move people onto EA111, which is a Demand tariff without the ToU Peak and off-peak rates. Tariffs won't remain flat for everyone.

Glad it was helpful!

Effective sun exposure is 4 hours .....

The Enphase Enlighten App

same for me...

Correction…It’s a backup battery…

@@darleneseaman4280 oh so what you’re saying is we need to buy extra equipment to apply that discount to our bills?

It’s an option, when you buy solar. If you choose, than yes. It another piece of equipment they have to install.

The main benefit of solar is to use it as it's generated to directly reduce your power bill. In the good old days we'd help people size up a system to match their daytime energy consumption, these days almost everyone sizes up the system based on their 24-hour usage because they will be purchasing a battery within the lifetime of the solar system. The feed-in tariff no longer matters now that we have battery storage, as you say.

@@SolarayEnergy Are you sure that's how it works in WA? I have 20 panels and my Dec bill for 59 days says I exported 1222 kw/h and imported 408kw/h. I am home all day so use power all day , just seems a lot of exported kw/h if I am using the solar as well? Maybe its setup to export everything and then we pay to import it again? it is Government owned Power company lol.

In Sydney a system produces about 4 times its size so a 5kW system will output 20kWh a day, on average, doing more in summer and less in winter.

Hey! 15min. interval is due to type of connectivity to gateway, meaning mostly your system is on wi-fi or ethernet. If it's on cellular, it goes around every 6hrs

❤❤

Still no...