Everything Homeowners Need to Know About Energy Tariffs, SEG Payments and Selling Electricity to the Grid
If you’ve invested in solar panels – or you’re planning to – you’ve probably heard terms like Octopus Flux, Smart Export Guarantee (SEG), Octopus Agile and selling electricity to the grid. Understanding how these energy tariffs work can make a significant difference to the return on your solar investment.
At SolarTherm UK, we help homeowners across Essex, Kent, Suffolk, Hertfordshire and the wider South East and East Anglia maximise the value of their solar PV systems. Choosing the right energy tariff is just as important as selecting high quality solar panels or battery storage.
This guide explains the difference types of electricity tariffs available, how export payments work and how to choose the best tariff for your home.
What Are Energy Tariffs?
An energy tariff is the pricing structure your electricity supplier uses to charge you for the electricity you import from the National Grid – and, in many cases, pay you for electricity you export.
For homes with solar panels, your tariff affects:
- Electricity import costs
- Export payments
- Battery charging strategy
- Overall savings
- Solar payback period
Modern smart tariffs can significantly improve the financial return from a solar PV system, particularly when combined with battery storage.
Why Energy Tariffs Matter for Solar Homes
Without solar panels, every unit of electricity you use must be purchased from your supplier. With solar, you generate your own electricity, using as much as possible within your home. Any surplus can be stored in a solar battery or exported to the grid for payment under the Smart Export Guarantee (SEG).
The value of every exported kilowatt hour depends entirely on your chosen tariff. Choosing the wrong tariff could mean earning substantially less for the same electricity generation.
Understanding Import vs Export
There are two separate parts of your electricity bill.
- Import: electricity purchased from the National Grid, usually used in the evenings and overnight when your solar is no longer generating electricity.
- Export: your solar panels generate electricity, but you may not use all of this self-generated power. Rather than it being wasted or your panels stop generating, you can sell this surplus electricity to your supplier for payment under the Smart Export Guarantee (SEG). This is known as selling electricity to the grid.
What Is the Smart Export Guarantee (SEG)?
The Smart Export Guarantee (SEG) is a government backed scheme requiring most licensed electricity suppliers to pay households for renewable energy exported to the grid. If your home generates surplus electricity from solar PV, you can receive payments for every unit exported.
The Smart Export Guarantee replaced the older Feed in Tariff (FiT) scheme for new installations in 2019. Benefits include:
- Earn money from surplus solar generation
- Improve solar payback
- Reduce overall energy bills
- Works alongside battery storage
Most modern solar installations are designed with SEG eligibility in mind when completed by an MCS certified installer.
How Does SEG Work?
Your export meter (normally part of your smart meter) records how much electricity leaves your property. Your supplier then pays you according to your chosen export tariff. The payment amount varies depending on energy supplier, tariff selected, time of export (for some tariffs) and wholesale electricity prices. Some suppliers offer fixed export rates, while others offer dynamic pricing.
Smart Meter Requirements
Most SEG tariffs require a smart meter, MCS certified solar installation, an eligible inverter and a registered export account. As an MCS certified installer, SolarTherm UK designs systems that meet current export requirements and can guide customers through the registration process after installation.
Fixed Rate Export Tariffs
The simplest option is a fixed export tariff. You receive the same payment for every exported unit regardless of the time of day, season or electricity demand. Advantages include predictable payments, easy budgeting, no need to monitor electricity markets and they are ideal for many homeowners. This suits customers who want straightforward returns without actively managing their energy usage.
Time of Use Tariffs
Time of Use tariffs charge different electricity prices throughout the day. Electricity is generally cheaper overnight and more expensive during peak demand. Time of use tariffs can also vary depending on national demand. These tariffs work particularly well alongside battery storage allowing you to charge batteries when electricity is cheap and discharge your battery during peak demand and expensive windows. This results in dramatically reduced import costs, contributing to higher long term savings.
What Is Octopus Flux?
One of the UK’s best known smart tariffs is Octopus Flux. Designed specifically for homes with solar panels, battery storage and smart meters. The tariff offers time based import pricing, time based export payments and higher export rates during peak demand. This allows homeowners to store cheap overnight electricity and export surplus power when payments are highest. For battery owners, Octopus Flux can significantly improve overall system performance.
Who Benefits Most from Octopus Flux?
Flux works well if you have solar PV, battery storage and smart home controls and especially well if you have flexible electricity usage where you can load shift to benefit most from your self-generated electricity and cheaper import periods.
Battery systems can automatically charge during cheaper periods before supplying your home later. Many homeowners across Essex and the South East see excellent returns when their battery is programmed correctly.
What is Octopus Agile?
Octopus Agile is one of the UK’s most dynamic electricity tariffs. Instead of fixed prices, electricity changes every half hour. Prices follow wholesale electricity markets.
Benefits include:
- Very low prices during periods of excess renewable generation
- Opportunity to reduce charging costs
- Excellent for battery owners
However, prices can also become much higher during peak demand. Agile is generally best suited to households comfortable managing their electricity usage.
Fixed Tariffs vs Smart Tariffs
| Fixed Tariff | Smart Tariff |
| Same price all day | Prices change throughout the day |
| Predictable bills | Greater savings potential |
| Simple to understand | Requires smart meter |
| Lower management | More active optimisation |
| Suitable without battery | Ideal with battery storage |
Neither option is universally better. The best choice depends on your electricity usage, battery capacity, solar generation and your lifestyle.
Battery Storage Makes a Huge Difference
Battery storage transforms how energy tariffs work. Instead of exporting all your surplus electricity immediately, your battery can store excess solar generation, power your home after sunset, charge overnight using cheaper off peak grid electricity and export electricity during higher paying periods. This flexibility can often increase overall savings substantially.
Selling Electricity to the Grid
Many homeowners ask whether selling electricity to the grid is worthwhile. The answer depends on:
- Export tariff
- Battery storage
- Self-consumption
- Household electricity use
Generally, using your own solar electricity first delivers the greatest savings because importing electricity costs significantly more than most export tariffs pay. However, exporting surplus electricity still provides valuable additional income through the Smart Export Guarantee (SEG).
Feed in Tariff (FiT) Explained
Before the Smart Export Guarantee (SEG), the UK operated the Feed in Tariff (FiT) scheme. The FiT paid homeowners for electricity generated and electricity exported. The scheme closed to new applicants in 2019. If you’re already registered your payments continue under your original agreement and existing contracts remain valid provided your system doesn’t change. New solar installations, since 2020, instead use the Smart Export Guarantee (SEG).
Which Tariff is Best?
There is no single best tariff for every household. Generally:
- Fixed Export Tariff: is ideal for smaller systems, homes without batteries and those looking for simplicity.
- Octopus Flux: this is ideal for those with battery storage, high solar generation and those looking for flexible energy management.
- Octopus Agile: if you are a tech savvy household and want automated battery systems and to control your own energy usage.
- Time of Use Tariffs: these are ideal if you want to incorporate EV charging, solar PV and battery storage as a complete system. Using cheaper overnight prices to charge your EV and battery and running your home using your battery during peak periods.
SolarTherm UK helps customers understand which tariffs complement their system and usage patterns, ensuring they get the best possible return from their investment.
Why Choose SolarTherm UK?
Choosing the right installer is about more than fitting solar panels. Our experienced in house team provides guidance on:
- Solar panel sizing
- Battery storage selection
- Smart energy tariffs
- Export payments
- Smart Export Guarantee registration
- Future proof system design
As an MCS Certified Contractor, NICEIC Approved Installer and EPVS Gold Standard member, every installation is completed to recognised industry standards, giving homeowners confidence that their system is designed for long term performance and eligibility for schemes such as the Smart Export Guarantee. We stay up to date with evolving energy tariffs and export requirements, ensuring customers receive advice based on current industry best practice rather than sales driven recommendations.
Whether you’re in Essex, Kent, Suffolk, Hertfordshire or across the wider South East and East Anglia, our team can recommend a system that delivers excellent financial performance today while remaining adaptable as the UK energy market evolves.
Why This Guide Matters
Understanding energy tariffs is just as important as choosing the right solar PV system. The right combination of import and export tariffs, whether that is fixed rate, time of use tariffs or Octopus Flux, battery storage and efficient system design can significantly improve your long term savings while reducing reliance on the grid.
At SolarTherm UK, we don’t simply install solar PV systems – we help homeowners optimise every aspect of their investment, from system design through to export payments and ongoing performance, ensuring customers across the South East and East Anglia get the maximum value from renewable energy.
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
The Smart Export Guarantee (SEG) is a government-backed scheme that pays homeowners for surplus renewable electricity exported to the National Grid.
Yes. If you have an eligible solar PV system, smart meter and export tariff, you can receive payments for excess electricity you export.
For many homes with solar panels and battery storage, Octopus Flux can improve overall savings by combining cheaper import periods with higher-value export rates. Whether it’s the best option depends on your energy usage and battery capacity.
The Feed-in Tariff (FiT) was the previous government incentive for solar installations and closed to new applicants in 2019. The Smart Export Guarantee (SEG) replaced it for new systems and only pays for electricity exported to the grid.
No. Battery storage isn’t required to receive SEG payments, although it can help you maximise savings by increasing self-consumption and allowing more strategic exporting.
Yes. We provide guidance on compatible energy tariffs, export payments and battery storage options so your solar PV system delivers the best possible financial return.
