Maximising your solar system Tariffs, export, self-consumption and battery scheduling
Your solar panels are generating free electricity. But how much of that turns into actual savings depends on when you use energy, what tariff you're on, and how your battery is configured. Most new owners leave £200–£500 per year on the table without realising it.
If your battery isn't charging, your tariff schedule isn't working, or your system isn't performing as expected, we can check your settings remotely.
Book a settings review — from £75 → ← Back to New Solar Owner hubSelf-consumption — the single biggest factor in your savings
Self-consumption is the percentage of your solar generation that your home uses directly, rather than sending it to the grid. It is the most important number for your financial return — more important than system size, panel efficiency, or which brand you have.
Every kWh you use directly saves roughly 24p (the current retail electricity rate). Every kWh you export earns between 0p and 15p. The gap between 24p and 4–15p is your self-consumption premium — and it's why increasing self-consumption is almost always the best first step.
Typical self-consumption: 30–50%. Most solar generation happens during the day when many households are at work. Surplus is exported. The main lever is shifting appliance usage to solar hours.
Typical self-consumption: 70–85%. The battery stores surplus daytime solar and releases it in the evening. Self-consumption above 85% usually means the battery is not big enough to capture all surplus, or evening consumption is very high.
Choosing the right tariff for your system
Your electricity tariff is the second biggest lever on your savings. The right tariff depends on whether you have a battery, how much you export, and how flexible your energy usage is.
Tariffs like Octopus Flux, Octopus Go, and Intelligent Octopus Go offer different rates at different times of day. Typically: cheap overnight (7–12p/kWh), standard daytime (20–24p/kWh), and sometimes a premium peak export rate (up to 25p/kWh). The strategy: charge the battery cheaply overnight, use solar during the day, and either use or export stored energy during expensive peak hours.
If you don't have a battery, or prefer simplicity, a competitive flat-rate import tariff combined with a good Smart Export Guarantee rate works well. You save the full import rate on every kWh you self-consume and earn the export rate on every kWh you send to the grid. No scheduling required — the system just does its thing.
Regardless of your import tariff, you should always have an export tariff in place. Without one, every kWh you export earns nothing. The SEG is free to sign up for and you can choose any participating supplier — it does not need to match your import supplier. Rates range from 3p to 15p per kWh. Even 4p/kWh adds up to £80–£120/year for a typical 4kW system.
Battery charge and discharge scheduling
If you have a battery and a time-of-use tariff, the battery schedule is where the savings happen. The concept is simple: charge when electricity is cheap, use or export when it's expensive. The execution involves getting the right settings configured in your inverter portal.
The exact times depend on your tariff. Octopus Go uses 00:30–04:30 for the cheap window. Flux uses 02:00–05:00. Agile has variable half-hourly rates, requiring a more dynamic approach — some systems integrate with APIs to automate this. Check your tariff details for the exact rate periods.
In your inverter's monitoring portal or app. Look for: "Timed charge", "Force charge", "Battery schedule", "Work mode", or "Energy management". The exact menu varies by brand. On GivEnergy, it's in the Battery section. On Sunsynk and Growatt, it's in the System Mode section. On SolaX, it's under Battery Settings.
When the clocks change in March and October, check your charge schedule. Some inverters use UTC internally and adjust automatically. Others don't — and your 02:00–05:00 charge window suddenly becomes 01:00–04:00 or 03:00–06:00, missing the cheap rate entirely. Our Flux guide covers the BST fix for each brand.
Load shifting — use free solar electricity for heavy appliances
Load shifting means running your highest-consumption appliances during peak solar hours instead of during the evening. It costs nothing, requires no new equipment, and can increase your self-consumption by 10–20 percentage points.
Use delay timers on your washing machine and dishwasher to start during peak solar hours. If you work from home, this is easy. If you're out during the day, most modern appliances have programmable start times. EV charging is the single biggest opportunity — charging your car during solar hours instead of overnight can absorb 7kW of solar generation for several hours.
Using your monitoring data to track and improve your return
Your monitoring portal shows you exactly where your energy is going. Learning to read this data is the key to ongoing optimisation — it tells you whether your settings are working and where the remaining savings opportunities are.
Common mistakes that cost new solar owners money
We see these repeatedly in diagnostic sessions. Each one is easy to fix once identified — and some can save £100–£300 per year.
Surprisingly common. If your installer didn't set up an export tariff, every kWh you export earns nothing. Fix: sign up for the Smart Export Guarantee — it takes 10 minutes and you can choose any participating supplier.
Many systems ship with timed charge disabled. If you're on a time-of-use tariff but the battery only charges from solar, you're missing the cheap overnight charging opportunity. Fix: enable timed charge in your inverter portal and set the window to match your tariff's cheap hours.
Your DNO may have imposed an export limit (commonly 3.68kW under G98). If this setting is configured incorrectly — limiting generation instead of just export — your system produces less energy than it should. Fix: check the export limit setting in your inverter and ensure it is configured as an export limit, not a generation limit.
A reversed CT clamp causes the inverter to misread import as export and vice versa. Symptoms include: battery not charging, system exporting when it should be self-consuming, or monitoring showing negative generation. Fix: an engineer or electrician can reverse the CT clamp orientation in under 5 minutes.
When the clocks change, some inverters adjust their schedules automatically and some don't. If yours doesn't, your battery charges at the wrong time — potentially at full rate instead of the cheap rate. Fix: check and adjust your timed charge window twice a year, in March and October.
Frequently asked questions
Self-consumption is the percentage of your solar generation used in your home rather than exported. It matters because using energy directly saves the full retail rate (~24p/kWh), while exporting earns only 3–15p. A system with 80% self-consumption saves significantly more than one at 40%, even with identical generation. Batteries typically increase self-consumption from 40–50% to 70–85%.
If you have a battery, almost certainly yes. Tariffs like Octopus Flux offer cheap overnight rates to charge the battery and premium export rates during peak hours. The battery charges cheaply, solar tops it up during the day, and stored energy is used or exported during expensive hours. Without a battery, time-of-use is less beneficial — a competitive flat rate plus a good export tariff may work out simpler and comparable.
In your inverter's monitoring portal or app, navigate to battery settings and look for timed charge or force charge. Set the charge window to your tariff's cheap-rate hours (e.g., 00:30–04:30 for Octopus Go, 02:00–05:00 for Flux). Set the target state of charge to 100%. Ensure the feature is enabled — it's often off by default. If the option isn't available, your inverter may need a firmware update or the feature may not be supported on your model.
The Smart Export Guarantee (SEG) is a UK government scheme requiring large energy suppliers to pay for your solar exports. You need an MCS-certified installation and a smart meter or approved export meter. Sign up with any participating supplier — it doesn't need to match your import supplier. Rates vary from 3p to 15p per kWh. Fixed-rate tariffs offer consistency; variable tariffs can pay more but fluctuate.
Common causes: the battery is already full, a timed charge schedule is overriding solar charging during the day, the charge rate is throttled by a settings limit, or the CT clamp is misconfigured so the inverter doesn't see surplus generation correctly. An export limitation setting can also interfere if misconfigured. Check the charge/discharge pattern in your monitoring for the last 24 hours to identify which applies.
The difference between a well-optimised system and an out-of-the-box configuration is typically £200–£500 per year for a 4kW solar + 9.5kWh battery system. The biggest gains: switching to a time-of-use tariff (£150–£300/year with a battery), setting up an export tariff (£100–£200/year), shifting heavy appliances to solar hours (£50–£100/year), and correctly configuring battery schedules (ensures tariff savings materialise). Exact figures depend on system size, consumption, and tariff choice.
Related guides
How SEG works, current rates, eligibility, and how to sign up with the best-paying supplier.
Full setup guide for Flux's three-period tariff, including brand-specific inverter configuration.
Battery chemistry, BMS, charge cycles, degradation — the technical foundation for battery scheduling.
Why CT clamp direction matters for battery charging, self-consumption, and monitoring accuracy.
How export limits work, what your DNO requires, and what happens when the setting is misconfigured.
Flat-rate vs time-of-use, Octopus Flux, Go, Agile — how to pick the tariff that matches your system.
What to check monthly, quarterly, and annually to keep your system performing at its best.
Not getting the savings you expected?
A remote settings review checks your tariff configuration, battery schedule, charge and discharge rates, CT clamp readings, and export limiter settings. We tell you exactly what to change and how much the fix is worth in annual savings.