Cloudy days, winter and night-time: What are the limits of solar?

By Mara Oct 22, 2020

There are a variety of questions to consider around the purchase of solar panels and a solar battery, but one we often encounter is with regards to the possible limitations on solar energy generation, namely, do solar panels work at night or when it’s cloudy, or can they only generate energy when the sun is out?

It makes a lot of sense to ask, particularly if you’re sitting at home browsing the Internet whilst it rains outside! That’s how the UK is a lot of the time; overcast and inconsistent. Sure, recent summers may have seen a glorious stretch of hot weather and clear skies for a few weeks, but the majority of the time this still isn’t the case. So, does bad weather hinder solar energy generation?

Do solar panels work when it’s cloudy?

We are used to cloudy weather in the UK, so as a homeowner looking to install solar panels and a solar battery we can understand why you may be worried about solar panel limitations, but we have good news.

Although a cloudy or overcast day is not the optimum condition for solar panels to generate electricity, they still can, even in limited daylight. This is because the solar panels do not need access to blazing sunshine to generate solar energy; they can do so from any clear access to daylight. Of course, the more direct sunlight the better when it comes to solar energy generation, but the bigger area where this factor comes into play is not so much when it’s cloudy, but when the sun goes down.

Do solar panels work at night?

This one is simple. No, solar panels do not generate solar energy at night.

This area highlights the seasonal factor with solar energy generation. For a significant part of the year, you will enjoy plenty of daylight hours during which your solar panels can generate energy. When it comes to the winter months, the much shorter daylight periods, coupled with the greater regularity of cloud cover, means that you will generate significantly less than in summer.

We’d estimate that it’ll probably be around a third of the solar energy produced when compared with the amount that is generated on a summer’s day. This is why we tend to talk about estimated savings in regards to annual energy bills where different savings can be averaged across a full year.

With this in mind, a key issue you may face with solar energy generation is that you’re not actually at home for many – or even any – of the daylight hours during winter. So, any energy generated by your solar panels would be of little use to your home energy needs and would return to the grid. Thankfully, we have something that can overcome solar panel limitations and maximise your solar energy potential.

How does a solar battery help?

We always recommend a solar battery installation alongside any solar panel installation. This ensures that as your solar panels make the most of any daylight to generate as much solar energy as possible, it is not only able to be used towards powering your home in the day, but can be directed to charging the solar battery for later use. This gives you the flexibility to make use of your solar energy at night, which in many homes is when the majority of energy consumption occurs through usage such as lighting, cooking and TV.

Another benefit that many will not be aware of is that through the winter months and cloudy days, when your solar panel systems are not producing as much energy, many homes can make use of time-of-use tariffs to charge their battery with cheaper energy during the night, to then be used to ‘make up the difference’ alongside the lower levels of solar energy generation in winter.

If this all sounds complicated to manage, don’t worry. For homes with time-of-use tariffs, our software can generate a personalised charging plan* which aims to power your home from the cleanest and lowest-cost energy available. In addition to our innovative solar battery options, we also offer the Moixa Dashboard and App which will help you understand your energy generation and consumption.

Does a solar battery have any other benefits?

Interesting you should ask that, as actually, yes it does! At Moixa, we offer our solar battery customers the opportunity to join GridShare Membership. This allows Moixa to unlock additional value from your battery by supporting the grid through a ‘Virtual Power Plant’.  GridShare Membership is one of the ways Moixa looks to support a low-carbon future, powered by renewable energy, by balancing the grid with spare battery capacity. If you join GridShare Membership, you receive an additional £50 per year for the first three years.

While you may have heard of the end of the Feed-in Tariff for new customers, there is now a new Government initiative, the Smart Export Guarantee, which came into effect in January 2020. This means that homeowners who send solar energy to the Grid can once again receive a level of financial reward. Exact figures will vary depending on how much you send to the grid and which energy company you are with.

Get in touch

At Moixa, we have provided our solar batteries to over 1,000 homeowners in recent years. If you visit our Request a Quote page to enter a few key details, we’ll get in touch to discuss a specific quote for your solar energy needs, our pricing and our flexible payment terms.

You can also call us on 0161 883 2374 or email on to speak to a member of our team. From there, we can offer more answers to your questions and put in motion the process of installing your solar panels and solar battery at your home.


*Automated personalised charging plans are only available for homes with predictable household consumption patterns, households without predictable consumption can still make the most of a time-of-use tariff through our static charging plans.