Frequently asked questions

What consequences does a period of prolonged heat have for the electricity supply in the Netherlands?

During periods of warm weather, power plants may have to limit their production of electricity if the temperature of the cooling water they use is too high and/or if the supply of cooling water is insufficient. If the total reserve capacity of electricity falls below a certain level as a result of restrictions on the use of cooling water, this can lead to electricity shortages in the Netherlands.

What consequences does a period of prolonged cold have for electricity supplies in the Netherlands?

During such periods, the demand for electricity will increase sharply. Producers may have problems obtaining sufficient fuel as coal transports by river come to a halt. Ice build up may slow down or even halt coal supplies at the plants themselves and gas supplies are also increasingly less secure. As a period of prolonged cold usually affects (western) Europe as a whole, neighbouring countries generally experience the same problems.

What is TenneT’s role during periods of prolonged heat that require the introduction of restrictions on the use of cooling water?

TenneT monitors the situation, issues signals to the various parties involved (electricity producers, regional grid administrators, Department of Public Works and Water Management, Ministry of Economic Affairs) and informs market parties in the energy sector when necessary. This is done by means of a system in which TenneT invokes different phases which indicate the size of the reserve capacity available within the Netherlands. It should be noted that TenneT has no power to influence the discharge of warm water in rivers.

What has changed compared to 2006?

A new assessment system has been introduced for the discharge of warm water (e.g. cooling water used by electricity producers). Under the previous system, a maximum temperature of 30 degrees applied to the discharge of cooling water. The new system takes more account of the ecological aspects of the temperature of the surface water into which the cooling water is discharged. The scope for warm water discharges is determined based on a set of ecological preconditions. These preconditions differ for each discharge point. Under the new assessment system, different permits can therefore be issued for different discharge points. As a rule of thumb, there is more room to discharge warm water into bodies of water and waterways that have strong currents, like the North Sea and the major rivers. On bodies of water and waterways with little circulation, the scope for discharging heat may remain the same or even decrease under the new system.

Will breaches be tolerated, as was the case in previous years?

The introduction of the new assessment system means that temporary exemption orders no longer apply, because the extension of the cooling water limits is included in the new permit. The new assessment system also stipulates that during a period of no more than one week in July or August, the water temperature may rise to a maximum of 32 degrees at the boundary of the dilution zone, provided that the overall surface water temperature exceeds 25 degrees. The period during which the maximum value is exceeded must be continuous and is strictly limited to one week per year.

Where can I check the temperature of the surface water?

The surface water temperatures measured at several different stations can be found at www.actuelewaterdata.nl (the water temperatures for the measuring station at Lobith can be found at www.aqualarm.nl).

Why do neighbouring countries allow unlimited discharge of cooling water?

Different regulations apply in the countries neighbouring the Netherlands. Every country has its own regulations.

When is TenneT given additional powers to influence the electricity market?

TenneT’s primary role is to issue signals to the parties involved. TenneT is given additional powers when there is an imbalance between supply and demand on the electricity market. In the event of such an imbalance, TenneT can take a number of measures to restore the balance, with the aim of safeguarding the security of supply. For instance, TenneT can deploy regulating, reserve or emergency capacity or invoke the so called ‘not normal situation’.

When is the electricity supply (partially) switched off?

In the exceptional event that TenneT can no longer maintain the energy balance, as a final measure it will order one or more regional grid administrators to switch off part of the load in their respective regional grid, to prevent worse from happening. It should be noted that this measure has never been taken during cooling water periodes.

How will TenneT inform the (market) parties involved?

TenneT will inform the parties involved about the different phases in an open and transparent manner and for as long as necessary. The energy market will be informed by e mail. The answers to the most important questions will be published on TenneT’s website.