A day in the life of an off-grid installer

Last week we installed a battery backup system on an existing grid feed solar system

We had previously installed a 2kwatt grid feed system about 4 yrs ago when the feed in tariff was 66 cents/kwhr.  The owner wanted the system expanded to include a backup battery bank and inverter.

This is the layout:

When the power goes off, thGrid feed with backupe SPPro, which is always synchronised with the grid, instantly takes over supplying house loads. In order to alert the owner that grid supply has stopped, an alarm sounds in the house so that steps can be taken to limit energy usage.

The 140 Amp hr battery set has about 4 Kwhrs of usable energy available to supply loads – which if managed carefully, can last for 4-5 hrs of use. Important loads would be the fridge, lights (especially at night), laptop and other necessary loads.

When running normally in grid mode, the solar system preferentially supplies any battery charging requirements and house load support, then any excess energy is exported via the Selectronic SPPro  inverter. We specified one of Selectronic’s GO series inverters which limits grid export to 2 kwatt (the original size of the array) This ensures that the original agreement with the retailer remains unchanged so that the 66cents feed in tariff is safe!

For the hardware, we selected the Selectronics MY Grid system click on link here
It looks very neat and tidy and the Selectronic mY Gridvery best thing about the whole system is –
It’s all designed and made in Australia


Battery Size – 140 Ahr
Battery Type – Absorbed Glass Matt (AGM)
Battery Voltage – 48v
Array Size            –   2kw
Available Energy for backup – 4 kwhrs
Likely support time – about 5hrs or more depending on usage
System Brand – Selectronic My Grid