Energy reports and grid updates are full of terms that don’t always come with an explanation. Intermittency is one of them.
You will often see it alongside phrases like “the problem with solar” or “the challenge with wind power”, which can make it sound rather alarming.
It isn’t a design flaw. It’s just a way of describing how these energy sources work.
What intermittency actually means
Intermittency, which you might also see called variable generation, simply means that solar and wind don’t produce electricity at the same level all the time. A solar farm generates power when the sun is shining. A wind turbine turns when the wind is blowing. When the weather changes, the energy output changes too.
That is a key way that renewable energies differ from a gas-fired power station, which can run at a fairly consistent level regardless of the weather. That consistency comes at a price: fuel costs, carbon emissions, and exposure to volatile global energy markets.
Intermittency is not a reason to dismiss renewables. It is a different challenge, and one that the energy system is getting better at managing.
A helpful way to think about it is rainwater. During a downpour, water arrives faster than you can use it. During a dry spell, nothing comes in at all. The answer is not to give up on rain. It is to build the right infrastructure to collect it, store it and use it when it is needed.
Why it matters right now
The UK is building more renewable energy into its electricity system, which means managing changing levels of generation is becoming more important. Solar and wind can produce large amounts of clean power, but the system also needs ways to store that power and move it to where it is needed.
This is where battery storage comes in. Large-scale battery systems can absorb surplus power when generation is high, such as during bright daylight hours, and release it back into the grid when generation dips or demand rises. RenewableUK notes that battery energy storage systems play an important role in smoothing periods of intermittency in renewable generation.
At Elements Green, our solar projects are increasingly developed alongside utility-scale battery storage for this reason. Our proposed Great North Road Solar and Biodiversity Park in Nottinghamshire, for example, is designed with this principle at its core, combining solar generation with battery storage from the outset. Capturing energy during peak daylight hours and using it later does not make intermittency disappear, but it does help smooth the supply curve and make solar a steadier part of the energy mix.
The bigger picture
Intermittency is sometimes used as an argument against renewable energy, as though the fact that the sun sets every evening is somehow a surprise. But the grid has always had to balance supply and demand. Power stations go offline for maintenance. Demand rises suddenly. Cold evenings happen. The system already manages change, and it is becoming better equipped to do so.
Intermittency is a logistics challenge. And logistics challenges have solutions.
The question is not whether renewable energy can work. It is how we build the infrastructure that lets it work as well as possible. With solar, storage and smarter grid planning working together, there is every reason to feel optimistic.
The question is not whether renewable energy can work. It is how we build the infrastructure that lets it work as well as possible. With solar, storage and smarter grid planning working together, there is every reason to feel optimistic.
