Britain’s electricity system is expected to remain secure this winter, but growing attention on energy resilience is prompting homeowners to consider what would happen if their power supply was interrupted.
As temperatures drop and households prepare for the colder months, the reliability of Britain’s energy supply is back in the spotlight.
According to the BBC’s report, Lights will stay on this winter, grid operator says after concerns, the National Energy System Operator (NESO) expects the country’s electricity system to remain secure throughout winter 2026/27, although some periods could place greater pressure on the network.
NESO has also highlighted the importance of managing periods when electricity demand is high and renewable generation is lower.
For homeowners, the message is reassuring. However, it also provides an opportunity to look at how solar panels and battery storage can help households take greater control of their energy.
Is Britain’s Electricity Supply Secure This Winter?
NESO’s winter assessment indicates that Great Britain should have sufficient electricity to meet expected demand throughout the winter.
It’s Winter Outlook 2026/27 highlights the challenges of balancing electricity supply and demand as the energy mix evolves, with wind, solar, gas-fired generation and battery storage all playing a role.
NESO has warned that there may be tighter periods, particularly during colder weather when demand increases and renewbale generation can fluctuate. These situations can require additional action from electricity generators to maintain the balance of the system.
Importantly, a tighter period does not automatically mean a power cut is likely. The system operator has measures available to help maintain supply.
Nevertheless, energy security remains an important consideration for households and businesses, particularly as electricity continues to play an increasingly central role in everyday life.
What Would Happen If Your Home Lost Power?
Even when the national electricity system is expected to remain secure, individual power cuts can still occur because of local network faults, severe weather or damage to infrastructure.
When the electricity supply is interrupted, a conventional grid-connected solar PV system will generally shut down automatically. This is an essential safety feature designed to protect engineers working on the electricity network.
That means having solar panels on your roof does not necessarily mean you will have electricity during a power cut. However, a compatible solar battery system with the appropriate backup equipment can be designed to keep selected circuits, or potentially much of your home, powered during an outage.
For homeowners who want to maintain access to essential appliances, lighting and other electrical equipment, this is where battery backup technology can make a difference.
How Whole-Home Backup and EPS Can Help
SolarTherm UK installs solar PV and battery storage systems, including compatible Hanchu ESS solutions. Depending on the equipment selected and the electrical design, these systems can incorporate backup functionality to provide electricity when the grid supply fails.
There are two important concepts to understand.
Whole-Home Backup with a Hanchu ESS Gateway
A compatible Hanchu ESS battery system paired with the appropriate gateway can be configured to provide backup power to a home’s electricity installation during a grid outage.
The gateway manages the changeover between the normal grid supply and backup operation. With a correctly designed and commissioned installation, this can allow the home to continue operating using available battery energy and, where supported by the system, solar generation.
The exact level of backup depends on the system configuration, available battery capacity, inverter capability and the electrical loads being supplied. Whole-home backup does not mean that every appliance can necessarily operate simultaneously without restriction.
EPS – Emergency Power Supply
EPS stands for Emergency Power Supply. It is a backup output available on compatible inverter systems, designed to supply designated electrical loads when the normal grid supply fails.
Depending on the system, an EPS arrangement can keep essential equipment operating, potentially including lighting, internet equipment, refrigeration and selected sockets.
An EPS installation is not automatically the same as whole-home backup. It may supply a dedicated set of backup circuits rather than the entire property. The available power, supported loads and changeover arrangements depend on the inverter, battery, installation and system design.
Can Solar Panels and Batteries Keep Working During a Power Cut?
With a suitably designed and compatible solar and battery system, backup power may be available even when the electricity grid is down. During normal operation, solar panels can generate electricity for household use, while surplus energy can be stored in the battery for later use.
During a power cut, a system equipped with the necessary backup functionality can isolate itself from the grid and supply supported loads from its battery and, where the configuration permits, solar generation.
This can help households make use of their stored energy when the grid supply is unavailable. However, backup duration is not guaranteed. It depends on the battery’s available charge, the amount of electricity being consumed, the power limits of the inverter and whether solar generation is available at the time.
A correctly specified system should therefore consider not only how much energy a household uses, but also which appliances the homeowner wants to keep running during an outage.
Is Battery Storage Worth Considering Before Winter?
Battery storage can offer benefits beyond backup power. When paired with solar panels, a battery can store surplus electricity generated during the day for use later, helping households make greater use of their own solar generation.
Depending on the system and electricity tariff, a battery may also be charged using lower-cost electricity at suitable times for use when electricity is more expensive.
For homeowners considering a new solar installation, or looking to add storage to an existing system, it is worth discussing both the potential energy saving benefits and whether backup functionality is appropriate for the property.
Not every battery installation provides power during a power cut, and backup equipment may need to be specified separately. It is important to establish this before installation rather than assume it is included.
Prepare Your Home for Greater Energy Resilience
NESO expects Britain’s electricity supplies to remain secure this winter, and there is no reason to interpret its outlook as a prediction of widespread power cuts. Nevertheless, energy resilience is about more than the national supply outlook. It is also about understanding your household’s energy needs and the options available if your own electricity supply is interrupted.
A solar PV system combined with compatible battery storage and appropriately designed backup equipment can help homeowners make better use of their own energy and maintain power to supported circuits during a grid outage.
At SolarTherm UK, we help homeowners across Essex, Kent, Suffolk, Hertfordshire and the wider South East and East Anglia explore solar panels, battery storage and backup options suited to their properties.
If you are considering solar panels or battery storage ahead of winter, speak to our team about your options, including compatible Hanchu ESS battery systems and gateway solutions.
Contact SolarTherm UK today for a free, no obligation quote and design, tailored to your property, usage and future energy needs. No hard sell, just honest, expert advice – and the time you need to make an informed decision.
Your home. Your energy. Your future.
Frequently Asked Questions
Most standard grid-connected solar PV systems automatically shut down during a power cut as a safety measure. However, a compatible solar inverter and battery system with suitable backup functionality can provide electricity to supported circuits when the grid supply is interrupted. The system must be designed and installed to operate safely in backup mode.
Yes, provided your battery system supports backup operation and has the necessary equipment installed. Depending on the configuration, a solar battery can supply essential circuits or provide whole-home backup. How long the power lasts depends on the battery’s available charge, electricity consumption, inverter capacity and whether solar generation is available.
EPS (Emergency Power Supply) typically provides backup electricity to designated circuits or a specific backup output when the grid fails. Whole-home backup is designed to supply a wider proportion, or potentially all, of a property’s electrical installation through suitable backup equipment such as a compatible gateway. The capabilities depend on the system design and the appliances being used.
Compatible Hanchu ESS battery systems can be configured for backup operation when paired with the appropriate compatible inverter, gateway and electrical installation. The precise capabilities depend on the equipment selected and how the system is designed and commissioned. SolarTherm UK can help homeowners establish which configuration is suitable for their property.
A Hanchu ESS Gateway is part of a compatible backup system that manages the property’s connection to the electricity grid and its backup supply arrangement. Depending on the system configuration, it enables the installation to isolate from the grid during an outage and supply supported household loads from the battery and, where supported, solar generation.
Potentially, yes. A compatible solar PV and battery system can be designed to continue generating electricity and charging the battery during a grid outage. However, this capability depends on the inverter, battery, gateway and backup configuration, as well as the available sunlight and the electricity being consumed in the home.
There is no fixed duration. Backup time depends on the battery’s usable capacity, the power required by connected appliances, inverter limits and the amount of solar electricity generated during the outage. Running essential appliances rather than high-demand equipment can help extend the available backup time.
Potentially, provided the appliances are connected to supported backup circuits and their combined electricity demand remains within the system’s limits. Refrigerators, lighting and internet equipment may be suitable for backup, while electric showers, immersion heaters, electric vehicle chargers and other high-power appliances may exceed the available capacity. Heating systems also vary in their electrical requirements.
A compatible gateway or other manufacturer-approved backup switching arrangement may be required, depending on the inverter and system design. A standard solar battery installation does not automatically provide whole-home backup. Your installer should confirm which equipment is needed to support the intended backup functionality.
Solar battery backup can provide additional resilience during power cuts, alongside the potential benefits of storing surplus solar electricity for later use. Whether it is worthwhile depends on your household’s electricity consumption, backup requirements, budget and the system’s capabilities. A professional assessment can help establish the most appropriate solution.
SolarTherm UK installs solar PV and battery storage systems for homeowners across Essex, Kent, Suffolk and the wider South East. Contact our team to discuss compatible battery storage options, including Hanchu ESS systems, and whether EPS or whole-home backup is suitable for your property.
