Hybrid solar and battery systems
Use surplus solar without draining your home battery.
Start with the right settings. If you need to prevent battery discharge during grid charging, ask your installer about separating the zappi supply.
Your solar panels and battery share one hybrid inverter. From the AC side, myenergi products cannot separate solar generation from battery discharge.
Start here
Two settings for normal ECO+ charging.
These help your battery take priority during surplus charging. They do not stop a third-party battery supplying a boost.
Set a small Export Margin
This leaves a little power exporting while zappi or eddi uses the remaining surplus. Some systems need 100 W or 150 W.
Set this on the master product. Menu names vary by model and firmware. Use your configured installer passcode.
Set Minimum Green Level
Use ECO+ with Minimum Green Level at 100%. This avoids topping up normal surplus charging from the grid or battery.
A lower MGL allows a top-up. That might make the battery discharge to support charging, even with an Export Margin set.
Other Settings → Installer Settings → your installer passcode → Supply Grid → Network → Export Margin
On a small screen, scroll sideways to follow the screens. Enter your configured installer passcode, rather than assuming the example code applies.
Remember the minimum charging power.
A single-phase EV charge needs around 1.4 kW available after the margin. With a 100 W margin, that means around 1.5 kW of total surplus before charging starts. Start and stop delays still apply.
Watch the setup video
Solar charging and boosts behave differently.
Choose a mode to see why the same settings do not cover every situation.
Wait for surplus, then charge.
Your battery gets the opportunity to take the solar first. With enough surplus remaining after the Export Margin, zappi starts charging. At MGL 100%, it pauses when there is not enough surplus.
The load draws from available power.
Boosting does not restrict the load to spare solar. If a third-party battery is supplying the house, it will also try to supply the EV or heater load it can see.
An alternative installation approach
Separate zappi from the battery’s view.
In some installations, a Henley block splits the supply after the meter. One branch feeds zappi’s distribution board. The other feeds the house distribution board, with the hybrid inverter connected on the house side.
The CT positions make the difference.
The inverter’s CT monitors only the house branch. It does not measure zappi as a household load, so normal battery control does not discharge to cover that load. The myenergi Grid CT still monitors the whole property, allowing zappi to detect surplus.
1. myenergi Grid CT: after the electricity meter and before the Henley block. It monitors both the house and zappi supplies.
2. Solar inverter CT: after the Henley block, on the house feed only. The dedicated zappi supply stays outside its measurement.
Conceptual single-phase example for discussion with your installer. This is not a complete wiring design. Scroll the diagram on smaller screens.
myenergi Grid CT
After the meter, before the Henley block. It measures the combined import and export of the house and zappi branches.
Solar inverter CT
After the Henley block, on the house feed only. The zappi branch stays outside the inverter’s household-load measurement.
These are different sensors with different jobs. Moving the myenergi Grid CT onto the house-only branch would exclude zappi from the total measurement.
Why a shared supply can cause problems
If the inverter and zappi share a branch that the inverter’s CT monitors together, the inverter sees EV charging as household demand. It might discharge the battery to meet it. Some systems also cycle between battery charging and surplus diversion as their controls respond to each other.
What changes with the separate-supply arrangement?
The installer connects the hybrid inverter on the house side and places its CT on the house-only feed. zappi retains its own branch, while the myenergi Grid CT remains before the split. A Henley block alone does not achieve this. The branch layout and CT positions must work together.
What your installer needs to check.
- Inverter export limitsThe inverter sees power flowing towards zappi as export. Its configured export limit might therefore restrict how much solar power reaches zappi, even when the panels could generate more. Any DNO requirements must remain satisfied.
- Different monitoring figuresThe inverter might record energy sent to zappi as exported energy. myenergi measures the property’s net grid flow when its Grid CT is correctly positioned.
- Deliberate battery exportThis arrangement prevents the battery responding to zappi as a household load. It does not stop zappi using energy the battery is deliberately exporting, where surplus charging conditions are met.
- Battery controls and smart schedulesStopping battery discharge or coordinating charge schedules is another option. Check that the battery controls cover the actual EV charging period, including tariff-controlled sessions.
- Installation suitabilitySupply ratings, circuit protection, inverter controls, CT requirements, earthing and local rules all need assessment. The diagram shows the principle, rather than a design suitable for every property.
Your next step.
For normal solar charging
Start with a 50 W Export Margin, ECO+ mode and MGL 100%. Check how your battery responds. Some systems need a higher margin.
For boosts without battery discharge
Check your battery’s discharge controls. If a wiring solution is needed, ask your installer to review the separate supplies and CT arrangement.