The Grid Congestion Problem: 'Policy makers could have scratched their heads a little sooner'

The limits of our electricity grid are in sight. In large parts of the Netherlands, the grid is so overloaded that no new companies can be connected in the coming years. In recent years, companies have switched en masse from fossil fuels to (green) electricity, municipalities are installing charging stations for electric cars and households are purchasing solar panels and heat pumps. As a result, supply and demand no longer match. 

What is grid congestion? 

Grid congestion creates a traffic jam on the electricity grid, Van der Laan explains. "Being stuck in a traffic jam is not really a disaster, except that it will increase your travel time a bit. If you generate extra power in the event of congestion on the electricity grid without any extra power consumption, there will be outages and failures on the grid." The congested grid is largely due to changes in supply and demand patterns. Due to the transition to wind and solar energy, the demand no longer matches the supply. "The overall demand for energy has not increased, but the peaks in supply and demand are more intense and at different times. In particular, a lot of solar energy is generated in the afternoon and wind energy when the wind blows. The demand for power is mainly in the morning when we wake up, but also when we come home at the end of the afternoon and want to charge the car, for example." 
  
Could the current problems have been avoided by intervening earlier? "It's a bit of a chicken-and-egg story," says Van der Laan, affiliated with ENTRANCE – Centre of Expertise Energy. "You're not going to reinforce the electricity grids if the demand isn't there yet. The transition to renewable energy has gone much faster than expected. However, researchers and grid operators have seen the problem coming for some time. Until 2020, grid congestion was not on the political agenda. Policymakers should have scratched their heads a little earlier. It is good that people are encouraged to switch to sustainable energy. But that also has consequences and too little thought has been given to that. At ENTRANCE, we try to help policymakers with this. For example, we are working on developing an instrument that helps policymakers to better assess the consequences of choices." 

'Concerns about electric heat pumps'  

Van der Laan is referring, among other things, to the construction of the countless solar parks. Too little thought has been given to the impact that solar parks have on the electricity grid. "Solar parks are far from ideal for the energy grid. Because the sun only shines on certain parts of the day, you have to deal with a peak load on the grid. But most of the time, a solar park is not running at full capacity, so it is a shame to reserve that peak capacity. Cable pooling can be the solution to better integrate solar parks into the grid. Cable pooling means connecting various sustainable energy sources, such as a solar park and wind turbines, to each other. By placing the sources closer together, you only need one connection to the grid. Of course, we should not close our eyes to the resistance to wind turbines. You have to take that seriously: the size of the wind farms has to be adapted to the environment."  

The professor also has concerns about the introduction of the (fully) electric heat pump. "From a grid congestion point of view, the switch to electric pumps can be disastrous, because the pump is used on cold days when people want to stay warm in their homes. The device will then need power throughout the day. You then get terrible peaks in the demand for power. A demand that we can hardly meet. Hybrid heat pumps are better in that respect, but we would like to get rid of gas. That's a bit contradictory. If we do all our heating with electric heat pumps, things will go wrong in terms of grid congestion in the coming years anyway. With hybrid heat pumps, you put much less strain on the grid because you can also use gas during peak times." 

Reinforcing the grid takes time  

The professor indicates that we will continue to suffer from grid congestion for some time to come. "A lot is currently being invested in reinforcing the electricity grid. The grid operators expect to invest more than 30 billion euros in the expansion of the electricity grid by 2030 alone. However, the procedures that allow expansion take a long time, land has to be purchased to make expansion possible and there is too little staff. The list of companies that cannot be connected to the grid will only increase in the coming years, I expect. We have to learn to live with it."  

How can we tackle grid congestion?   

Reinforcing the grid will take years. How can we curb grid congestion in the meantime? The use of batteries in which energy is stored is one possible solution, says Van der Laan. "The roll-out of batteries is accelerating at the moment. The big advantage of batteries is that you only need a fraction of the grid connection. The urgency to use batteries, especially for business parks where there are many large-scale consumers, is currently greater than ever. For households, the costs do not outweigh the benefits yet, but I foresee that smaller batteries will become increasingly affordable in the future."  

Researchers from ENTRANCE are involved in the ‘Groningen Stroomt Door-project’. "The fact that companies can take action together to do something about grid congestion is underexposed," the project says. Van der Laan: "Groningen Stroomt Door was founded to limit capacity problems of the electricity network on business parks in and around the city. The first pilot will take place at the Westpoort business park. Existing companies have a connection to the grid, but there is currently a waiting list for the other plots on the site. As a result, the lots are difficult to sell. We have calculated that a few small or one large battery can help to connect more companies to the grid. The questions we still face, are: where do we place the batteries and who pays for the costs? For the time being, companies do not want to pay for the cost of a battery." 
  
The Groningen Stroomt Door-project also maps out how much capacity companies use from the electricity grid. By jointly recognising peak moments in generation (feed-in) and off-take of electricity and coordinating supply and demand, the capacity of the grid can be better utilised. In general, smarter use of the grid is a solution to the problem of grid congestion, says Van der Laan. "You can see that several pilots are already running, for example, you can only charge the car at times when there is no peak load on the grid. You can also think of making solar panels smarter, whereby the efficiency of the panels is slightly reduced at certain times to prevent overloading of the grid. In that case, it will take a little longer for households to recoup the solar panels, but it will allow you to limit grid congestion." 
  
However, it is not always possible to make smart use of the grid, Van der Laan observes. In January, TenneT, the operator of the high-voltage grid, announced that, unlike the grids of the regional grid operators, there are also peaks on the high-voltage grids at other times, i.e. outside the usual peak times in the morning and evening. "For example, energy generated in wind farms in the North Sea is sold to neighbouring countries such as Germany and Belgium. This power then runs through TenneT's high-voltage grid," says Van der Laan as one of the reasons. "It is a worrying message, because smart use of the grid is actually one of the ways to tackle grid congestion. For the time being, TenneT's message only applies to the Flevopolder region, Gelderland and Utrecht, but if we have to deal with this throughout the country, we definitely have a big problem on our hands." 

'Saving energy helps'  

Van der Laan notes that the current government has done a lot of work to tackle grid congestion. "We had a competent cabinet and the minister made the right decisions to combat grid congestion. The question is whether this will also be the case in the future. I hope that we will not be blinded by electric heat pumps and will also look at alternatives such as heat networks and combined heat and power plants running on hydrogen or green gas. In addition, I do have a message: saving energy still has a major impact on reducing grid congestion. Let’s keep the focus on that!"