As the UK energy market continues to evolve, more EV drivers are looking beyond the price of a home charger and asking a more practical question: how can I reduce the cost of charging my car?

For many households, the answer is to combine a reliable home EV charging point with an electricity tariff that offers lower rates at certain times of day.

Some EV tariffs provide a fixed overnight off-peak window, while dynamic tariffs can change their prices throughout the day. In both cases, moving more of your charging away from expensive daytime periods can help reduce running costs.

The important part is choosing a tariff that suits your driving routine and setting your charging schedule correctly.

How EV Tariffs Work in the UK

EV tariffs generally fall into two categories: fixed time-of-use tariffs and dynamic tariffs.

Fixed Off-Peak EV Tariffs

Fixed time-of-use tariffs offer a lower electricity rate during a defined daily period, usually overnight. The start and end times are published by the energy provider, making them relatively straightforward to plan around.

Octopus Go is one example of this type of EV tariff. Other providers, including OVO, also offer EV-focused plans or charging add-ons, although their eligibility requirements and pricing structures vary.

For drivers who normally plug in overnight, a fixed off-peak tariff can provide a simple and predictable way to reduce charging costs.

With a charger such as the Injet Eco, users can manually check the lower-cost hours shown by their electricity provider and create a corresponding charging schedule in the app.

This type of manual scheduling does not require a direct integration between the charger and the energy supplier.

Dynamic Electricity Tariffs

Dynamic tariffs work differently. Products such as Octopus Agile can change their electricity price every 30 minutes, with the following day’s prices normally published in advance.

Prices may be lower when demand is reduced or renewable generation is high. Occasionally, rates can become very low or even negative, but these periods are not guaranteed.

A dynamic tariff can offer greater potential savings, but it also requires more attention. Users need to check upcoming prices and manually decide when they want their vehicle to charge.

For drivers who prefer a consistent routine, a fixed off-peak EV tariff may be easier to manage. Drivers with more flexible schedules may find a dynamic tariff more suitable.

What Is the Best EV Tariff?

There is no single best EV tariff for every UK household.

The right option depends on:

• Your daily mileage

• How much energy your EV normally needs

• When your vehicle is parked at home

• The tariff’s peak and off-peak unit rates

• The daily standing charge

• The length of the lower-cost charging window

• Whether you have a compatible smart meter

• Whether the tariff has specific vehicle or charger eligibility requirements

• How much other household electricity you use during peak periods

A tariff with a very low overnight rate may appear attractive, but it could also have a higher daytime rate or standing charge. It is therefore important to compare the complete tariff rather than looking only at the advertised EV charging rate.

Using the Charge At Home App for Scheduled Charging

The Charge At Home app gives Injet Eco users a straightforward way to manage their home charging routine.

Instead of relying on the charger to select an electricity tariff or calculate energy prices, users remain in control of their charging schedule.

A typical setup involves four steps:

1. Check the current rates and off-peak hours shown by your energy provider.

2. Open the Charge At Home app.

3. Set the charger to operate during the lower-cost period.

4. Plug in the vehicle and allow the schedule to start charging at the selected time.

If your tariff changes its rates or charging window, you can update the schedule in the app.

This approach works particularly well with fixed time-of-use tariffs because the lower-cost period normally remains consistent from day to day.

For a dynamic tariff, users can review upcoming prices and manually adjust the charging schedule when appropriate. Because dynamic rates can change every day, they require more active monitoring than a fixed overnight tariff.

The charger does not automatically retrieve or respond to half-hourly tariff prices unless a specific integration with the energy supplier has been confirmed.

Why Reliable Connectivity Matters

A home EV charger is often installed outside, in a garage or at the edge of a driveway where the household Wi-Fi signal may be weaker.

Reliable connectivity helps users:

• View charger status

• Monitor charging sessions

• Start or stop charging remotely

• Update charging schedules

• Review charging information

• Receive charger notifications

The Injet Eco Pro offers connectivity options designed for installations where reliable remote access is important. Depending on the selected model and configuration, this can include Wi-Fi, Bluetooth and 4G connectivity.

A secondary connection can be particularly useful when the charger is installed a long distance from the home router.

Hardware Designed for Reliable Home Charging

Reducing charging costs is not only about selecting an electricity tariff. The charger itself must also provide reliable operation, appropriate safety features and convenient controls.

App-Based Scheduling

Scheduled charging allows users to decide when the charger should provide power to the vehicle. This makes it possible to align charging with the fixed off-peak periods published by an energy provider.

Dynamic Load Balancing

Dynamic load balancing monitors household electricity demand and adjusts EV charging power when necessary. This can help prevent the combined household load from exceeding the available electrical capacity.

Solar Charging Support

For homes with solar panels, compatible charging modes can help make better use of locally generated electricity. Actual performance will depend on the solar installation, charger configuration, household demand and available generation.

OCPP Support

OCPP provides an open communication standard for compatible charger-management platforms. This can be valuable for installers, landlords and organisations that may need broader charger-management options in the future.

OCPP support should not be confused with automatic compatibility with every domestic energy tariff. Tariff eligibility and supplier-controlled charging depend on the individual energy provider and its current list of supported vehicles and chargers.

UK Smart Charging Compliance

Private domestic and workplace chargepoints sold in Great Britain are generally required to comply with the Electric Vehicles (Smart Charge Points) Regulations 2021.

These regulations cover areas such as smart functionality, scheduling, security and the ability to send and receive information. Regulatory smart functionality does not mean that every charger automatically connects to every electricity tariff.

How Much Could Off-Peak Charging Save?

Potential savings depend on the difference between your normal electricity rate and your off-peak rate.

For example, if one charging session draws 30kWh from the grid:

• At 25p/kWh, the session would cost £7.50.

• At 8p/kWh, the same amount of electricity would cost £2.40.

• The potential difference would be £5.10 for that charging session.

This is only an illustrative example. Actual costs depend on:

• Your current tariff

• The amount of electricity drawn from the grid

• Charging losses

• How much of the session fits inside the off-peak window

• Your EV’s onboard charging limit

• Your home’s electrical supply

• Any changes to tariff rates or times

If a charging session is longer than the available off-peak period, some electricity may be charged at the higher daytime rate.

Fixed Off-Peak or Dynamic Tariff: Which Is Better?

A fixed off-peak EV tariff may be more suitable if you:

• Prefer predictable charging times

• Usually plug in overnight

• Want to set a recurring schedule

• Do not want to monitor electricity prices every day

A dynamic tariff may be worth considering if you:

• Can change your charging times frequently

• Are comfortable checking prices in advance

• Can avoid charging during expensive peak periods

• Understand that low or negative rates are not guaranteed

Neither option is automatically better for every household. The best EV tariff is the one that produces the lowest overall bill based on your actual charging and household electricity use.

Why Choose the Injet Eco?

The Injet Eco is designed to combine reliable home charging with practical energy-management features.

Depending on the selected model and installation, key features can include:

• App-based charging control

• Recurring charging schedules

• Wi-Fi, Bluetooth or 4G connectivity

• Dynamic load balancing

• Solar charging support

• OCPP compatibility

• Tethered and untethered options

• Outdoor weather protection

• Compliance with applicable UK smart charging requirements

For drivers on a fixed off-peak electricity tariff, the scheduling feature provides a simple way to plan charging around lower-cost hours.

This is manual time-based scheduling and should not be interpreted as direct integration with Octopus Energy or another electricity supplier.

Conclusion: Take Control of When You Charge

A home EV charger does not need to predict electricity prices to help reduce charging costs.

For many households, the most practical approach is to select a suitable time-of-use tariff, check its current off-peak period and use the charger’s app to create a reliable charging schedule.

Drivers using dynamic tariffs can also review upcoming prices and manually adjust their schedules, although this requires more regular attention.

By combining the right electricity tariff with reliable scheduled charging, UK EV owners can make home charging more convenient and potentially reduce the amount they pay for every mile driven.