Wind turbines and solar panels are easy to spot across our landscape. But how does the variable energy they generate supply the power grid without causing issues? Generation and demand do not always tally. And significant overproduction or underproduction of energy can negatively affect  the grid operation, as we saw during the large scale blackout that affected the UK in August 2019.

Our Professor of Power Systems Engineering, Professor Victor Becerra, knows that control technology is essential for the successful integration of clean renewable energy into the power grid. He wants to help ensure the nation benefits from reliable, safe and secure access to sustainable energy.
 

Harnessing nature

Renewable energy is crucial for a more sustainable future, free from fossil fuels. In the UK there is a significant amount of wind generation. Solar is on the rise, too. 

But using natural resources such as wind or the sun to generate electricity can have its downsides. They are not constant and some aspects of their variability can be difficult to predict. The wind doesn’t always blow and the cyclical nature of the sun, along with weather impacts on sunlight, all affect energy generation levels.
 
Victor explains: 

‘Control systems can be used in different ways to address the challenge of integration of intermittent renewable generation to the power grid. For example, they can be used to govern the charge and discharge cycles of energy storage devices. So storage devices are charged when there is excess of renewable generation. And discharged when there is a deficit.’

Active Network Management is another important and innovative control technology currently being used in power distribution grids in the UK. This type of control system  takes frequent measurements of key electrical variables at specific points in the network to control flexible demand and renewable generation. This prevents too much energy being fed into the network at once - if necessary, by restricting generation levels of renewable sources. This avoids exceeding the thermal capacity of power lines,  stabilises the network voltages, and avoids outages and system faults. 
 
Control systems can be used in different ways to address the challenge of integration of intermittent renewable generation to the power grid.

Victor Becerra, Professor of Power Systems Engineering

Demand response schemes are another way to support the integration of variable renewable energy. They enable energy customers to adjust their electricity demand automatically, dependent on supply. This helps maintain the balance between supply and demand of power on the grid. 
 
Victor is also involved in improving the adoption of solar energy. He’s working on a project in the 2 Seas area of northern Europe, which includes the south of England. It’s looking at ways to stimulate the growth or uptake of solar energy - from the residential level, to whole towns - through a series of solar energy technology demonstration projects, delivered across the partnership, in both urban and rural environments, and on domestic and public buildings. 
 

Supplying the baseload

While issues with the intermittent nature of renewable energy persist, more constant sources are needed to supply the baseload, which is the minimum electricity demand over a time span. This is where nuclear power comes to the picture in some countries, as a component of the energy mix that is particularly suited for that job. Nuclear plants provide a steady supply of carbon free power. But what about safety?

If something goes wrong at a nuclear power plant that causes a significant release of radioactivity into the environment, there can be negative consequences for humans and ecosystems alike. Not only in the vicinity of plants, but farther away as radioactivity can be spread by the atmosphere.
 
There are many mechanisms in place at existing nuclear power plants that make them extremely reliable and safe. But very occasionally there may be accidents or near misses, as has occurred historically in Fukushima, Chernobyl and Three Mile Island, for example. Victor’s work on control systems for nuclear power plants is helping them to become even more tolerant to faults. Adding elements of fault tolerance to nuclear power plant control systems makes the whole system smarter and safer.  

Enhancing the ability of wind and solar to provide a reliable power supply is starting to answer our clean energy demands. And enabling safe, clean nuclear energy to help supply the baseline demands means we are on the way to fossil fuel free energy generation - with cleaner air to follow.