We just installed a 50 kW alpha ESS battery. The most logical usage would be to charge the battery during the daytime so that we are capturing our solar energy into the battery and then to feed any excess power that we are not using back into the grid in the evening from 6 pm to 9 pm when there are bonus rates for exporting. Here’s the problem. There is no way to set your home battery to export manually during these peak times.
I was assuming that I could just set my battery to export for example from 6 pm to 9 pm at night and this would allow me to boost the grid when it’s most needed and recharge the battery the next day using my solar. I was quite surprised when there was no way to export from the battery. I rang the installation company and they said this is due to NSW or Australian regulations that do not allow you to control when you manually export from your battery.
The real cost of electricity in New South Wales is that it’s cheaper in the daytime and much expensive at peak times like breakfast and dinner. So you want to EXPORT in peak times and IMPORT or charge form solar during off-peak times.
I found three possible solutions. None of them are perfect but they are all a step in the right direction.
Step one is the simplest.
1. Regular electricity provider with a VPP.
You can sign up for something called a VPP, a virtual power plant. You use electricity as normal, charging your battery from solar and using your battery to power your home. At times that the provider chooses, they can take electricity from your battery to charge the grid. This is turning complete control of your battery over to the electricity provider. AGL have a VPP plan. Origin have a VPP plan. This allows them to charge your battery when they want and discharge your battery when they want. They generally pay you a good fee (e.g $1 per kWh exported). They control your battery 100%. You have no control over the VPP exports. And they pay you a set rate, lower than the actual electricity prices. So it’s basically a way for them to make money by using your battery, and give you a percentage of that. Very clever for them.
2. Amber ‘wholesale’ prices
There’s a company called Amber who offer you wholesale rates on electricity prices. They also give you an app that allows you some control over your battery. (You can choose to import and export in 1/2 hr blocks. And they also have some automation to charge and discharge your battery at the times they think is best to make you money. It’s very complex, because for most of the daylight hours in the day electricity prices to export are negative (yes it COSTS you to put electricity into the grid!) It’s hard to manage this because if your solar panels are generating and your battery is full you will lose money. It’s enlightening to see the actual electricity prices in real time. (I’ve seen them as high as $21.10/kWh (you make $21.10 per kWh to sell to the grid) and as low as -$0.95 (they pay you 95c per kWh to import! That’s right – they pay you to use electricity!
Being paid to use electricity.
Good export price.
3. Hack your Battery/inverter to override the inbuilt settings
If you are an engineer you can use Home Assistant to control your battery via Modbus. I found these instructions to be easy to follow and they work for an Alpha ESS battery system.