To add, the 300W of AC output would be pulled from the 100% batteries until the state of charge goes down to 99% and then your AC300 would pull from solar to re-charge the battery and this would repeat.
The B300 battery is rated at 3500+ Cycles to 80% of original capacity. If you charged it and discharged it once a day, you would go through 3650 cycles in 10 years. By that time you’ll likely see even better energy storage technology.
I suggest investing first in a Kill-a-watt or similar watt meter device which measures your power usage over time in kilowatt hours. For example, your maximum power consumption at a given point in time might be 1500W but is that all of the time? If it’s all the time then it would use up all the energy in a single B300 battery in less than 2 hours (3000Wh * 0.8 inverter efficiency loss / 1500W load = 1.6 hours). A second example is if your average load is 500W then the calculation would be 3000Wh * 0.8 inverter efficiency loss / 500W load = 4.8 hours.
Thank you for the answer.
I am using Schneider PowerTags to measure my usage. The current load is around 800-900W, but I plan to upgrade, and the max would be 1.5kw 240V. But is it correct that I can only use 80% of the B300 battery power? Same as with UPS?
It’s due to the overhead associated with the AC inverter because it needs power itself to run the circuitry to convert DC to AC - the industry standard is around 85% efficiency.