How to Set Up Night Charging on a Duracell Energy Battery & Inverter
If you're on a cheaper overnight electricity tariff, charging your Duracell home battery during off-peak hours can help reduce your electricity bills and ensure you have plenty of stored energy ready for the day ahead.
In this guide, we'll show you how to correctly set up night charging on your Duracell solar battery, explain the recommended charge rates, and highlight some common mistakes that can stop your battery from operating as expected.
Why Set Up Night Charging?
One question we're often asked is whether night charging should be enabled throughout the year. For most customers, night charging is primarily used during the winter months when there is less daylight available and solar generation is reduced due to poorer weather conditions.
During autumn and winter, your solar panels may not generate enough energy to fully charge your battery, making overnight charging a great way to ensure your system starts each day with a healthy level of stored energy.
In contrast, many customers find they do not need to use night charging during the spring and summer months. With longer daylight hours and increased solar production, the battery can often be fully charged by solar alone during the day.
Many electricity suppliers now offer cheaper electricity overnight, typically between:
1:00am - 8:00am
2:00am - 9:00am
(depending on your supplier and the time of year).
By charging your home storage batteries during these low-cost periods, you can use that stored energy throughout the day instead of buying electricity at peak rates.
Step-by-Step: Setting Up Night Charging
Step 1: Open the Duracell Energy App
Log into your Duracell Energy app and navigate to the main system screen.
Step 2: Select the Battery Icon
Tap the battery icon to access the battery settings or go to the navigation menu and select scheduled control.
Step 3: Select "Charge Time"
Choose Charge Time and enter your preferred charging window based on your electricity tariff.
For example:
Start Time: 3:00am
End Time: 6:00am
Step 4: Save Your Settings
Save the changes and allow the system a few minutes to update.
Step 5: Toggle Charge Time ON
Once you've entered the charging schedule, make sure you toggle Charge Time ON.
This is one of the most common reasons customers believe their schedule isn't working.
Important: Do NOT Set a Discharge Time
One of the most common mistakes we see is customers setting both a charge time and a discharge time. Setting a discharge schedule can result in stored battery energy being exported back to the grid when this isn't your intention.
For most homeowners, the goal is to:
✅ Charge cheaply overnight
✅ Store that electricity
✅ Use it throughout the day
❌ Not automatically sell all of the stored energy back to the grid
Recommended Charge Rates
Your battery charge rate should generally be matched to the inverter size.
3.68kW Inverter
Recommended charge rate:
3000W
6kW Inverter
Recommended charge rate:
5000W
These settings typically provide a good balance between charging speed and system performance.
Example Setup
If you have:
A 6kW inverter
A 16kWh battery
An overnight tariff
A normal wake-up time of 6:00am
We would recommend:
Charge Time: 3:00am - 6:00am
Charge Rate: 5000W
We generally recommend that charging finishes around the time you get up. The reason for this is simple. A battery cannot effectively charge and supply your household demand at the same time. If the battery is still charging when you start using appliances in the morning, you may end up importing electricity from the grid while the battery continues charging.
By ensuring the battery has completed charging before you start your day, you maximise the value of your cheaper overnight electricity.
Check If Variable Rate Tariff Algorithm Is Enabled
If your battery appears to be charging or not charging at unexpected times, it's worth checking the Variable Rate Tariff Algorithm setting.
If enabled, this feature can act like an AI energy management system and may automatically adjust charging schedules based on tariff information from your electricity provider.
If you want full control over your charging schedule, you may wish to disable this feature and rely on your manually programmed charge times instead.
Electric Vehicle Charging and Battery Charging
Many customers with a My Energi Zappi car charger or other branded EV chargers ask if they can charge their EV and battery at the same time.
While it may be possible depending on the property supply and system size, running both together can place a significant demand on the system.
In some cases, charging the car and battery simultaneously may:
Cause system overloads
Trip protective devices
Prevent either the vehicle or battery from charging correctly
For this reason, our recommendation is charge the vehicle first. Then allow the battery to charge afterwards during the remaining off-peak period. Splitting the charging times helps ensure both systems receive the power they need and helps avoid interrupted charging sessions.
Final Thoughts
Night charging is one of the simplest ways to maximise the value of your Duracell solar battery. Set your charging window to match your cheaper electricity tariff, ensure the charge schedule is switched on, avoid setting a discharge schedule, and check that the Variable Rate Tariff Algorithm isn't overriding your settings.
Combined with the correct charge rate and EV charging schedules, your battery can deliver maximum savings and help you get the very best from your solar energy system.
As trusted solar panel suppliers serving homeowners across Northern Ireland, we specialise in designing and optimising systems that deliver real savings all year round.
Whether you're considering a new battery installation, upgrading an existing system, or looking for advice we're here to help!
Contact Solarfix today for a free, no-obligation consultation and discover how much you could save with a properly configured solar and battery system.
