Article sourced from SolarQuotes
A home battery system that appeared to be performing well on paper delivered a costly surprise for one Australian household, highlighting the importance of correct system design, energy monitoring and inverter selection.
Louise Potgieter, SolarQuotes customer, installed a 24 kWh (kilowatt-hour) battery system and 15 kW (kilowatt) inverter with the expectation of significantly reducing her electricity bills. Prior to installation, her household electricity bill averaged around $670 per quarter, despite exporting more solar energy than it imported from the grid.
After the battery was installed, Potgieter monitored the system remotely while travelling overseas. The monitoring platform suggested the household was largely self-sufficient, with grid imports generally below 5 kWh per day. Based on those figures, she expected a substantial reduction in energy costs.
Instead, the next quarterly bill was almost identical to the previous one.
Investigating the discrepancy revealed a significant mismatch between utility billing data and the battery system’s monitoring platform. While the retailer reported more than 1280 kWh imported from the grid, the monitoring system showed only 261 kWh. After extensive troubleshooting, the cause was traced to an installation issue.
The battery system had been configured to monitor only the main house load, excluding the pool and shed. As a result, significant electricity consumption occurred outside the visibility of the home energy management system.
This meant excess solar generation was not always directed to those loads, reducing self-consumption and increasing grid imports. The issue was ultimately resolved by relocating the monitoring gateway to the main switchboard, allowing the system to accurately measure all energy entering and leaving the property.
According to Potgieter, the experience demonstrates the importance of understanding how an inverter measures energy flows and whether it can ‘see’ all loads connected to the site.
Modern inverters now play a central role in household energy management, coordinating solar generation, battery charging, grid imports and exports. Accurate metering at the main switchboard enables these systems to optimise energy usage and provide reliable backup power during outages.
Potgieter also highlighted the growing influence of innovative retail electricity plans. After switching to a tariff offering three hours of free electricity each day, the household now charges its battery during the free period and uses stored energy throughout the evening and overnight.
The experience also reinforced the value of inverter sizing. Larger inverters can charge batteries more quickly, support higher household loads and provide greater flexibility for future additions such as electric vehicles or extra battery capacity.
For homeowners considering battery storage, Potgieter’s advice is: Ensure the monitoring system captures the entire property, ensure you understand how the inverter operates and what sort of home energy system design you require long-term.
To better understand if you have the right inverter for 3 free hours of power, read Potgieter’s full review on the SolarQuotes website.
