Find the best times to run appliances and maximise your solar usage
Enter your solar system details and daily routine, then tell us when you typically run your main appliances. We’ll show you exactly when to shift your usage to maximise free solar power and estimate how much you could save.
Self-consumption is the percentage of your solar generation that you use directly in your home, rather than exporting to the grid. Higher self-consumption means more free electricity and faster payback on your solar investment.
Every kWh you use directly saves you the full retail electricity rate (currently ~24.5p/kWh). This is the most valuable use of your solar power.
Electricity you don’t use gets exported. You earn the SEG rate (typically 4-15p/kWh) — less than half what you pay for grid electricity.
The maths is simple: If you use 1 kWh of solar directly, you save ~24.5p. If you export it and buy grid power later, you might earn 10p but spend 24.5p — a net loss of 14.5p. This is why self-consumption matters.
Understanding when your panels produce the most power is key to timing your appliance usage. Peak generation depends on your roof orientation and the season.
| Roof Orientation | Peak Generation Time | Best Time for Appliances |
|---|---|---|
| South | 11am – 3pm | 11am – 2pm |
| South East | 9am – 1pm | 10am – 12pm |
| South West | 1pm – 5pm | 2pm – 4pm |
| East | 7am – 12pm | 9am – 11am |
| West | 2pm – 7pm | 3pm – 5pm |
Most UK households use the majority of their electricity in the evening (6-9pm) — cooking dinner, watching TV, running the washing machine after work. Unfortunately, this is exactly when solar generation drops to near zero.
Typical self-consumption without changes: 25-35%
Not all appliances are created equal. Here’s a guide to which ones offer the biggest opportunity for shifting:
Your daily routine has a huge impact on how much solar you can realistically use. Here’s what different households typically achieve:
Typical: 25-35%
Out during peak solar hours. Use timers to run appliances while away. Can reach 40-50% with smart scheduling.
Typical: 40-55%
Great position to use solar directly. Run appliances during breaks. Can reach 60-70% with awareness.
Typical: 45-60%
Flexibility to time activities around solar. With conscious effort, can reach 65-80%.
Typical: 30-50%
Variable patterns mean some days are great, others less so. Average out to moderate self-use.
Most modern washing machines and dishwashers have delay timers. Set them to start at 11am or 12pm even when you’re at work. It costs nothing and can boost self-consumption by 10-15%.
If you can’t use timers during the week, batch your laundry for sunny weekend afternoons. One sunny Saturday can handle a week’s worth of washing using entirely free solar power.
Laptops, tablets, phones, and power tools — plug them in during solar hours. Each device is small, but it adds up over a year.
If you have an immersion heater, consider using a solar diverter (like iBoost or Eddi) to automatically heat your water with excess solar. This can use 2-3kW of surplus generation that would otherwise be exported.
In summer, run air conditioning during peak solar. In winter, boost your heating during the sunny afternoon window. Your home acts as thermal storage.
For most UK installations, the 10am-2pm window offers reliable, strong generation even in spring and autumn. If you can only shift one appliance, time it to run during this window for maximum benefit.
A home solar battery is the ultimate self-consumption booster. It stores surplus daytime generation for evening use. Typical results:
However, solar batteries cost £4,000-8,000. The optimisation techniques in this guide are free and can get you partway there. Consider a battery if you’ve already maximised behavioural changes and want to go further.
Self-consumption opportunities vary significantly by season:
| Season | Generation (4kW system) | Peak Hours | Optimisation Potential |
|---|---|---|---|
| Summer | 18-22 kWh/day | 6am – 8pm | High — lots of surplus |
| Spring/Autumn | 10-15 kWh/day | 8am – 5pm | Moderate |
| Winter | 3-7 kWh/day | 10am – 2pm | Limited — less surplus |
In winter, generation is low enough that you’ll likely use most of it naturally. Focus your optimisation efforts on the sunnier months when surplus is highest.