Why is South Australia moving forward with Flexible Exports?
South Australia is leading the world in solar uptake. We all know the benefits and how great solar power is in reducing and eliminating our electricity bills. With more homeowners gravitating to solar power, the pressure on South Australia's existing infrastructure has surfaced resulting in current inverters tripping off, ramping down solar production or completely shutting down due to the grid voltage ranges going over the parameters of the inverter. It usually only happens for a short period of time in the middle of the day in spring as summer.
Keeping in mind during the day a solar power system will feed the home free electricity first and whatever the house does not need it sells back through to the grid
Currently when inverters trip off etc, the house will also loss the benefit during this time. The solution has always been not to control the inverter production by shutting it down but to control it at the feed in level where the issue really is. To do this, we need smarter interaction between solar systems and the electricity network.
The answer is Flexible Exports
Remember me saying "during the day a solar power system will feed the home free electricity first and whatever the house does not need it sells back through to the grid". Introducing Flexible Exports is addressing this issue so the house still gets what it needs during this short period of time and the grid issue is controlled at the feed in level and not the home.
Over the years, when having a solar power system installed, we have been imposed with restrictions such as using feed in tariff limiters to 5kw of inverter per phase to help avoid these future blackouts and current inverter issues. Other Australian states and most other countries in the world have zero feed in allowed. We are lucky here in South Australia, solar customers will soon be able to feed more energy into the grid, at the right times, thanks to this new project funded by the Australian Renewable Energy Agency (ARENA)
What are the options?
Option 1. Fixed Export Limit
- Fixed export option of 1.5kW per phase (vs the current 5kW per phase)
- Permanent and fixed limit, all year round.
Option 2. Flexible Export limit
- Enabled by smart internet-connected inverters – these receive regular export limit updates from SA Power Networks, and match exports to available grid capacity.
- Variable export limit that automatically adjusts between 1.5kW up to 10kW per phase (subject to available network capacity at the customer’s location throughout the day and the reliability of the customer’s internet connection).
Analysis shows the flexible export limits will typically be at 10kW for 98% of the time. This is double what we are currently allowed and more than makes up the different of the 2% of time not feeding back to the grid.
- Fix Export Limit to 1.5kw - This will be a cheaper upfront option when buying a solar power system as you will not need the extra equipment that is needed for the flexible exports option (2). You will need a feed in tariff limiter (smart meter) that matches the inverter you have chosen. Through the feed in tariff limiter (smart meter), the solar power system will limited to 1.5kws (of inverter) feed in at all times.
- Flexible export limit up to 10kw per phase. This option will cost a little more, upfront, to install the solar power system. This gives consumers as well as our infrastructure (SAPN - Electricity Network) a win win approach by allowing the consumer to export up to 10kw per phase (More than our current rules which are 5kw per phase) as well as the home not being disadvantaged and also protecting the grid during high feed back times when they will lower the feed in during that period. This will happen about 2% of the time so 98% of the time you will be able to export up to 10kw of inverter (more than what we are currently allowed).
