You may have heard the term Dunkelflaute in the media.

It is a German word used to describe a prolonged period of time with little wind and sunshine (translated as “dull weather”). Days with cloudy skies with low wind can be serious for an energy system heavily reliant on wind and solar energy.

Is it a problem? Critics of renewables (yes they exist!) point to periods of Dunkelflaute as evidence that renewables can’t sustain our energy needs long-term. While it is true that “bland” weather can limit the effectiveness of solar and wind farms, it certainly does not make them unviable. Naturally the weather does eventually change and in the meantime there are stop-gap solutions.

One of these is battery storage – although in its infancy, this technology has the potential to store up energy for times when wind and sun are lacking. In fact we have been exploring battery storage at our own sites, you can read more about this on our website.

Pumped storage is another solution. Pumping water upstream when demand is high then using it to generate hydropower when the sun and wind are absent.

So, while it is good to be aware of “dull” weather patterns, it is by no means something to fear and certainly does not completely limit the feasibility of renewables.