Strategic pillar 4: excellent network management

Our energy networks are among the most reliable in the world. We will ensure they remain so in the future. Thanks to efficient management, we are keeping the existing networks affordable. We also consider it important that customers experience more convenience and trust when we carry out work for them.

Safe infrastructure

Customers expect us to ensure a safe infrastructure and to guarantee their safety when we carry out our work. The safety of networks for everyone involved is our highest priority. A safety culture is essential for an infrastructure that is safe for our employees and other stakeholders. The possibility that incidents could occur in the gas or electricity grid means a targeted approach is crucial. We are also working in other ways, and in different areas, to prevent unsafe situations arising for our employees and the environment:

  • We are working on replacing and closing medium-voltage stations that have limited or inadequate protection. As this will take some time, additional measures aimed promoting safe working practices in such spaces will apply until this work has been completed. These measures will remain in force until these installations have been replaced by closed installations.

  • In 2014, a gas explosion in Diemen resulted in the loss of two lives. The Dutch Safety Board recommended the digital registration of gas connections in buildings with multiple connections, such as blocks of flats. During the year under review, Alliander mapped out the connecting pipes of more than 8,000 buildings with multiple gas connections.

In 2018, there was one lawsuit related to the health and safety of customers or third parties.

Reliability of supply of energy networks

In 2018, customers were without electricity for 30.6 minutes (2017: 20.9 minutes) on average. In the year under review, there were four major power failures, some of which were caused by safety systems that were not working properly. In addition, compared with 2017, there were 30% more outages in the medium-voltage network, with a huge peak in outages in the hot summer. This was because the persistent drought dried out the soil, reducing its thermal resistivity, which put additional strain on cables. That said, a positive effect on the outage duration was seen in places where we have implemented our digitisation strategy to a large extent, such as in the north of Noord-Holland. In those areas, we can localise disruptions more quickly and manage technicians more effectively. In Amsterdam, we are working on simplifying the local electricity grid. As this grid has become extremely complex over the years, simplifying it may help us to resolve outages more quickly, among other things. 

Gas outages are relatively uncommon (in 2018, 0.5% of customers were affected by a gas outage). The main cause of fluctuations in the gas outage duration are random large-scale outages that leave customers without a gas supply for a long time. Many of these outages are isolated, non-recurring incidents.

Preventing excavation damage

In 2018, Alliander became part of an alliance that aims to prevent damage to cables and pipes caused by excavation activities. In this context, it is important to ensure contractors and excavation workers are aware of the risks associated with their work and of the need to register the work beforehand with the Cable and Pipe Information Centre (KLIC) run by the Netherlands Land Registry and Mapping Agency (Kadaster).

Annual electricity outage duration1
  • 1 The average figure for the Netherlands for 2018 was not known at the time of publication.
Repeat outages

The number of unique cable numbers with more than five outages per year was on target (maximum of 17), thanks in part to choices made when prioritising work. This decline comes after several years in which there was a rising trend in repeat outages. The increases seen in 2016 and 2017 were chiefly attributable to the fact that more excavation work was carried out in those years, which had an impact on the number of outages due to damage to networks during excavation work. Damage caused by excavation work in the past is particularly likely to result in repeat outages. A sharper focus on repeat outages, combined with more effective preventive actions, resulted in the improvement seen in 2018 compared with 2017.

Annual gas outage duration1
  • 1 The average figure for the Netherlands for 2018 was not yet known at the time of publication. 
Causes of gas outage duration (2018)
Causes of electricity outage duration (2018)

Major outages in 2018

In 2018, there were four major power outages, two of which occurred in Arnhem and Amsterdam. In February, some 52,000 households in Arnhem went without electricity for several hours. On 9 March, a major, complex outage occurred in the Amsterdam city centre. An electricity cable was cut by workers, resulting in a short circuit and fire in the Frederiksplein distribution substation. The consequences of the outage were very evident in the centre of Amsterdam. A total of 28,000 households were without power for a long time, the Rijksmuseum was evacuated and many of the trams came to a standstill. Liander arranged for a detailed investigation to be carried out. The cause of the outage turned out to be a safety system that was not working properly. If a live cable is accidentally cut, this causes a short circuit. In such situations, the cable is normally switched off by a back-up safety system within a few seconds, but this did not happen in Amsterdam due to a defective fuse. 
We introduced measures in response to this outage. A system that constantly monitors the safety systems had already been installed in nearly all of the 250 stations in our service area, enabling us to prevent similar incidents. This system still had to be installed in a small number of stations, and we expect that this will happen by the end of March 2019. Until that time, technical specialists from Liander will continue to check the safety systems on a regular basis.

Infrastructure maintenance

In 2018, we spent € 954 million on the maintenance, replacement and construction of our energy infrastructure (2017: € 816 million). When it comes to infrastructure maintenance, every region has its own priorities, approach or characteristics. An overview of our investments in the energy networks in each region is available on

New switching station in Middenmeer

In 2018, we worked on renovating and expanding the electricity network in various locations. In Middenmeer, TenneT and Liander worked together on the construction of a brand-new switching station and a number of new cable connections. This new station is needed to connect the Wieringermeer wind farm, which will be one of the largest wind farms in the Netherlands, with a hundred turbines supplying green power to some 280,000 households. The work is expected to be completed by the end of 2019.

Feasibility of installing connections

The growing economy has led to a rapid increase in demand for capacity. Businesses in particular require more capacity so they can increase their production capacity. In addition, the energy transition is picking up pace, and renewable energy is being generated in more and more places. To cope with this, many new connections, upgrades to existing connections and thicker cables are required. The number of applications for new connections and upgrades go way beyond the plans for infrastructure development. At the same time, there is a severe shortage of people with technical skills. As a consequence, it is not always possible to install the required connections within the statutory 18-week time frame. Moreover, in some parts of the electricity grid a backlog of work has arisen with regard to the expansion of the underlying network (thicker cables). This results in a sharp increase in the number of transmission restrictions. A transmission restriction means that the customer still has a connection, but this does not have the capacity the customer requires. 
The network operators and partners in the chain are working together on solutions aimed at helping to reduce the time taken to install connections and ensure adequate transmission capacity. Moreover, the network operators want to provide clear information on what can, and what cannot, be achieved within the 18-week time frame. They held in-depth discussions on this matter with the Netherlands Authority for Consumers & Markets (ACM) during the year under review. 

Improving our operational processes

During the year under review, we made fundamental changes to how we organise our operational processes, partly in response to the increased workload and the shortage of technicians. These changes have enabled us to continue to improve our performance in terms of promptness, productivity and cost-awareness. 

Prior to 2018, the department responsible for the renovation and renewal of our networks worked in teams that consisted solely of engineers, project managers or construction supervisors. The department now works in multidisciplinary teams that include project managers, engineers and construction supervisors. Together, they are responsible for a number of projects. As a result, there is a sharper focus on ensuring projects are carried out in accordance with the agreements reached (with the customer or otherwise), and on making the best possible use of available engineering capacity. 

Moreover, during the year under review, we experimented with outsourcing entire projects to contractors. They handle the preparations as well as implementation, which includes linking up to network, enabling us to handle more work together. Based on this experience, a major procurement process was launched at the end of 2018. 

When planning our work, we determined the amount of time our activities would take on the basis of fixed, average standard lead times. We analysed which factors affect these standard lead times, such as the presence of any soil contamination. By using more flexible standard lead times in projects, we can now plan and manage our work more accurately and effectively. In this context, we applied more appropriate standard lead times for the first time in 2018.

Our results in the regions


Major housing developments are under way in the Arnhem-Nijmegen urban area. During the year under review, we expanded the infrastructure in various places so that energy can be supplied to new homes. With regard to Nijmegen-Noord, preparations for a new distribution substation near Ressen are well under way. Moreover, additional facilities are required in east Gelderland so that solar and wind energy can be generated locally. Within that region, we worked on connecting the Den Tol wind farm to the existing distribution substation in Ulft. Further expansion of this station is ongoing.


Friesland advocates renewable energy and energy saving measures. In 2018, we put a great deal of effort into preparing for the expansion of the Wolvega and Oosterwolde distribution substations and carrying out the associated work. We continued to install connections for energy generated by solar panels on the roofs of farm buildings and connected new producers of green gas to the gas network. We worked closely with stakeholders, such as housing associations, to make districts and homes natural gas-free. With a view to ensuring the adoption of heating develops along the right lines, we helped to prepare a heating vision for Friesland’s towns and cities.


The Haarlemmermeer area is home to a large concentration of data centres, notably around the A4 motorway. The local network does not have the capacity to cope with the demand for electricity in this area, which remains high. To cater to the explosion in demand for energy in Haarlemmermeer, we are consulting with national transmission network operator TenneT, the municipality and residents to find a suitable location for adding new capacity to the area. We worked hard on preparations for a new distribution substation in Wieringermeer. The substation is necessary given all the plans that exist for generating wind energy in this area. 


Demand for energy is increasing in Amsterdam due to population growth and the activities of businesses such as data centres. The city is also making a conscious effort to move forward with the energy transition. The number of solar panels increased, more homes were weaned off natural gas, and initiatives were in place for electric car mobility. Demand for energy around the Zuidas financial district is rising faster than expected, making an upgrade necessary. We therefore worked on two new distribution substations and the revamping of the Zorgvlied station. Preparations are well under way for a new distribution substation on a new island in IJburg.


In view of the growing demand for electricity in the Zuidplaspolder, in 2018, we joined forces with network operators Stedin and TenneT to examine the feasibility of a new distribution substation. In anticipation of this, we intend to organise a flexibility market to match electricity supply to demand. We installed a connection for excavating a tunnel in the vicinity of the Rijnlandroute, which will link the A4 and A44 motorways, and relocated the load of the Leiden distribution substation to another station. We also repositioned cables and pipes.


Flevoland is an extremely suitable area for wind generation. The issue here is to ensure that generated energy can be fed into the electricity grid in all circumstances. In Almere, we reinforced the energy network to facilitate growth in the number of homes, businesses and data centres. We also made a start on expanding the De Vaart distribution substation. We applied for dispensation for the new direct current (DC) network at Lelystad Airport Business Park, which we were given approval for at the start of 2019. 

Investments by region 


Investments (€ million)

Number of smart meters installed



















Other (mainly Kenter and Alliander AG)