What is the average solar panel’s output per day in the UK?

Solar power truly is a wonderful thing. Just think about it. Harnessing the power of the Sun (a bright star that’s been shining for over four billion years) to tap into a never-ending supply of clean, renewable energy, giving you greater energy independence, and saving you money too. Wow.

According to NASA, the Sun's power output is approximately 3.8 x 10^26 watts (W), and of this, the energy that reaches Earth's outer atmosphere is approximately 1,361 watts per square meter (W/m²). It’s a little hard to get your head around, so before you reach for your calculators, let’s break that down to what it means for you and your home.

Average daily production and output per day.

A typical 4 kW solar panel system in the UK will harness the Sun's power to produce an average daily output of around 8.8-11.0 kWh per day.¹ For those of us that skipped physics class, that equates to a significant portion of an average household's daily electricity needs.

To put it into perspective, it's roughly enough to:

• Power a washing machine for 4-5 full cycles (assuming 2.1 kWh per cycle).²

• Run a TV for about 50-60 hours (0.18 kWh per hour).²

• Boil a standard kettle around 50 times (0.2 kWh per boil).²

• Keep your fridge-freezer running for approximately 18 days (0.55 kWh per day).²

So broadly speaking, a typical 4 kW solar system can comfortably cover the daily electricity demand for lighting, entertainment, and essential kitchen appliances in the average UK home. This serves as a solid baseline of energy independence, which can be optimised even further through smart energy management, battery storage to capture excess solar generation, and adjusting energy consumption habits to align with peak solar production.

Solar energy system efficiency with batteries.

Solar batteries, like the ones we offer at E.ON Next, are essentially large rechargeable units for your home that act as an intelligent energy bank. During the day, when your solar panels are generating more electricity than your household is actively using, this excess energy isn't immediately sent back to the grid. Instead, it gets stored directly into your solar battery, allowing you to "bank" your self-generated, free electricity for when you need it most.

Key advantages of solar batteries:

• Maximises self-consumption. A battery lets you use more of the free electricity your solar panels generate. Instead of exporting excess power back to the grid for minimal gain, you can instead store it and use it during peak hours when grid electricity prices are typically higher.

• Reduced energy bills with solar. Because you’re cutting down the amount of electricity you need to buy from the grid (especially at the peak times), you’ll see your energy bills come down!

• Greater energy independence. Having your own energy supply and storage capacity means you rely less on external energy suppliers, protecting you more from fluctuating grid electricity prices.You'll also rely less on the grid. This can be a huge help during times of high demand, as it eases pressure on the whole power network. That means more stability and reliability for everyone. Plus, you'll be better off even during grid outages.

• Enhanced cost savings. Beyond just lower bills, a solar battery allows you to truly "break free" from constant grid reliance, making greater long-term cost savings by maximising the use of your own low-carbon, self-generated energy.

• Ups your renewable energy use. Perhaps most importantly, a solar battery ensures that a larger proportion of the clean energy generated by your panels is actually used within your home. This improves your home's environmental footprint as well as the efficiency of your renewable energy investment.

Make the most of your energy with Next Smart Saver!

So let’s imagine you’ve got your solar panels and now a battery to store any excess energy you generate. Did you know there’s a great way you can then maximise the value you get from this extra energy? It’s called a time of use (ToU) tariff. And as the name suggests, these are tariffs where instead of paying the same price for electricity all day long, the price changes depending on when you use it.

Typically, you’ll get cheaper rates during ‘off-peak’ hours (usually overnight, early mornings, or midday) when fewer people are demanding power. Time of Use tariff prices are usually a bit higher during the ‘peak’ hours, like when everyone gets home from work and starts cooking dinner or watching TV (often 4 pm-7 pm). This dynamic pricing gives you a fantastic opportunity to really make your solar energy and battery storage work smarter for you.

Next Smart Saver is a new time of use tariff from E.ON Next. It gives you the option to use your electricity at a lower price during the ‘off-peak’ hours of 5am-4pm and 7pm-2am, and at an even lower price during ‘super off-peak’ hours of 2am-5am, with a higher price for the ‘peak’ hours of 4pm-7pm. This tariff is already becoming popular with our customers who are benefiting by shifting their energy use to the off-peak periods – but if you have solar panels and a battery, you may be able to unlock even more value. Let’s see how that could look in a simple illustration.

An energy day in the life.

Imagine you have a 4 kW solar panel system, a battery, and have switched to our Next Smart Saver tariff. Your solar panels will typically generate around 10 kWh of electricity per day. And during the daytime, you might use around 4 kWh for your immediate needs. But, instead of exporting the remaining 6 kWh back to the grid for a modest payment, you instead store it in your solar battery. Later, in the evening as we approach the peak hours (4pm-7pm), you can intelligently use the energy from your stored 6 kWh in your battery. This means you’re essentially powering your home without purchasing expensive electricity from the grid during its priciest period.

Solar charging during off-peak.

While a solar battery's primary job is to store the energy generated by your rooftop panels, they often can do a lot more, especially when paired with a smart tariff. This allows you to make savings when you charge your battery up from the grid during off-peak hours.

On days when your solar panels aren't generating as much power, your battery might not be fully charged. In this instance, rather than drawing expensive electricity from the grid during peak times, you could simply top up at the cheaper periods (if you’re on a ToU tariff, like E.ON Next Smart Saver). Many modern solar battery systems can be programmed to automatically detect and charge themselves only during these low-cost windows.

This strategic charging ensures that you're always buying electricity at its absolute lowest price, storing it away, and then using it to power your home later, particularly during peak times (when grid prices would otherwise be at their highest). It's a clever way to further reduce your overall energy costs and maintain maximum energy independence, even when the Sun isn't shining so brightly.

You have the power.

It’s an exciting time in energy. Thanks to a combination of technological advancements and innovative tariffs like Next Smart Saver, our customers are becoming more empowered and in control of their energy.

Ultimately, when it comes to solar, by understanding your home's average daily solar output, and what you can store in your solar battery, you’re able to then manage your electricity smartly and efficiently. And it’s becoming easier too. We know adopting new tech or tariffs can sometimes feel daunting, so we’re on hand to offer support and guidance around smart home integration.

Why not check out our solar panel and battery solutions today, plus learn how our Next Smart Saver tariff can complement these to revolutionise your home energy and make you savings. Contact us here for a personalised assessment of your potential daily solar output and the savings you could achieve.