Secure and Reliable Energy Supply


Uniper reserve power plants as a percentage of those used for grid stabilization in Germany (3.2 of 4.7 GW)

38.2 GW

Uniper generation capacity helps ensure a reliable energy supply in seven countries

Almost 91%

Availability factor of our conventional power plants

8.5bn cubic meters

Gas storage capacity1

No incidents

or fines in conjunction with the delivery of products and services to customers

Keeping the Energy Supply Secure and Reliable

Germany’s energy transition proceeds apace. Renewable energy is increasingly prevalent in other countries as well. Most is wind and solar. Germany alone had about 90 GW of installed renewables capacity in 2016, consisting of more than 28,000 wind and 1.5 million solar facilities. The growth of renewables presents the energy system with numerous challenges. For starters: what happens when the wind doesn’t blow and the sun doesn’t shine?

On cloudy, windless days it doesn’t matter how many wind turbines and solar panels have been installed. They alone can’t ensure a reliable energy supply. That’s when our flexible power plants and energy-storage facilities step in. Consumers in large industrialized countries expect an uninterrupted energy supply. What’s more, key industries and thus economic prosperity depend on this. 

Our extensive portfolio of power stations (hydro, gas, and coal) makes us one of Europe’s biggest energy companies. We’re converting some of our coal-fired power plants to burn biomass. In Sweden, we also operate nuclear power plants.

Energy-storage facilities, long-term gas procurement contracts, and regasification capacity for LNG are also part of our portfolio, which plays a key role in ensuring that consumers can continue to rely on their power and heat supply.

We also provide engineering services and project-development consulting to other companies. For example, we help them run their assets smoothly, provide their customers with an uninterrupted energy supply, and raise their own energy efficiency.

Flexible, technologically advanced hydro, gas, and coal power plants can do what wind and solar can’t do by themselves: ensure a reliable and completely controllable supply of power around the clock. Conventional power plants provide crucial backup for renewables and will therefore help make the energy transition a success going forward.

Klaus Schäfer Chief Executive Officer

Energy for cloudy, windless days

Nowadays, everyone takes electricity for granted. We can watch television, listen to music, or run the dishwasher whenever we want to – 24/7, 365 days a year. But the energy market is experiencing dynamic change, particularly in Western Europe. This change is driven primarily by energy policies and targets. The German federal government, for example, intends for renewables to meet 40% to 45% of the country’s energy needs by 2045. Yet by 2022, Germany’s remaining nuclear power stations will be shut down, eliminating a large source of reliable power.

Solar and wind emit no carbon. But the sun doesn’t shine every day and the wind isn’t always sufficiently brisk. This happens more often than people may think. It happened in Germany on January 24, 2017, particularly in the windless predawn hours. At that time, most wind turbine blades stood still. But across the country people were getting out of bed, turning on the lights, and turning up the heat to start the day.

Where does electricity come from on days like this? It comes from reserve power plants that have the ability to balance out the fluctuations in renewables production: gas-fired plants that meet peak demand and technologically advanced coal-fired power plants that can ramp up quickly when needed or reduce their output when the wind begins to blow harder.

We operate power plants at a variety of crucial points in Germany’s energy system. Our plants can respond to fluctuations in renewables output fast and flexibly. This enables them to ensure grid stability and a reliable energy supply when challenges arise.

Security of supply needs in Germany

Our new coal-fired power plants, such as Maasvlakte 3 in the Netherlands and Datteln 4 in Germany (which is scheduled to come onstream next year), set industry standards for efficiency and environmental performance. Energy and Process Efficiency They can ramp up and down swiftly in response to fluctuations in renewables production. Once operational, Datteln 4 will be able to balance out several hundred megawatts of fluctuation in wind output within a few minutes.

The relevance of reserve power plants for a successful energy transition is enormous: in Germany, the number of grid stabilization measures through reserve power plants to avoid large-scale blackout has increased significantly. This is having a corresponding effect on the costs of the power system. For example, in the winter of 2015-2016 (from October to April), reserve power plants were brought online on seven days. During the same period in 2016-2017, they were dispatched on 93 days. The determining factor for this is the weather: considerable amounts of excess wind energy from northern Germany can’t be rerouted to the south of the country and therefore overload the grid. This situation isn’t expected to change, since grid expansion simply can’t keep pace with the growth of renewables capacity. In short, our reserve power plants will remain crucial for ensuring a stable power supply.

To respond swiftly, gas-fired plants in particular always need to be in standby mode. We’re enhancing the already high flexibility and efficiency of some of our plants to further shorten their ramp-up times. For example, we’re currently upgrading two combined-cycle gas turbines (CCGTs) in Great Britain:

In 2016 we began upgrading Cottam Development Centre, a CCGT that entered service in 1999. The aim is to increase Cottam’s energy efficiency by 4.5 percentage points to 58% and shorten its ramp-up time by about 50%. Scheduled for completion in 2017, the project will significantly reduce fuel consumption and carbon emissions.

We’re also enhancing the efficiency of Grain CCGT, located on the southeast coast of England. Once the work is completed, Grain will use 46% less fuel for hot starts (when it’s ramped up from minimum load), because its ramp-up time will be reduced to 48 minutes.

The volatility of renewable, particularly wind, will increase the need for minute reserve capacity (capacity that can be brought online very quickly). Below are our fleet’s average ramp-up times broken down by technology.

< 30 minutes

Ramp-up time for newest gas-fired power stations2

< 5 minutes

Ramp-up time for run-of-river power plants

90 seconds

Ramp-up time for pumped-storage hydroelectric stations

Some of our strategic power plants are so crucial for Germany’s supply security that the transmission network operator won’t let us shut them down, even though this would make sense from an economic perspective.

In Germany a power plant only makes money when it produces electricity. Given the expansion of renewables – and the prioritization of feeding energy generated from these into the grid – electricity generation in particular from gas-fired plants is in clear decline. This means that there is no assurance that they can operate economically. However, these power plants are urgently needed for reasons of supply security and grid stability and are also “demanded” by the grid operator. This supply-guarantee service, which every electricity customer in Germany relies on, is not appropriately remunerated. What’s more, power-plant owners are forced by the existing statutory framework to provide this service at a price level below cost. The framework prioritizes supply security but doesn’t appropriatly remunerate it. This needs to change, as the importance of these reserve power plants will increase in the years to come. After all, the fire department isn’t paid according to the amount of water it uses to put out fires, but for getting to fires quickly and putting them out whenever required.

Grid instability does indeed lead to higher risks of outages. Backup plants wear out faster due to permanent operation in stand-by mode as well as frequent ramp-ups and ramp-downs. They therefore need more maintenance than in the past – with a higher possibility of plant downtime the inevitable result.

In 2016 the amount of power we could have produced from our conventional fleet was equivalent to 19.2 TWh (sum of total planned and unplanned outages), enough to meet the demand of 5 million households3 for a year.

Outages in 2016 (planned, unplanned)

Conventional fleet Average availability
Total planned outages
Total unplanned outages






















United Kingdom




Figures do not include power plants in Belgium (Langerlo sold in January 2016; Vilvoorde in strategic reserve and not operational).
1Power plants go offline (unplanned) e.g. due to technical defect.
2Power plants go offline (planned) e.g. due to maintenance.

Stored energy as a backup

For the energy transition to succeed, Europe not only needs flexible generating capacity. It also needs other ways to keep the energy supply secure. One way is to store surplus renewable electricity produced on particularly sunny, windy days for later use. Electricity can be stored in a pumped-storage hydroelectric station, in the natural-gas pipeline system, and in batteries.

Reliable energy reserve from pumped-storage hydroelectric stations

We have just under 2 GW of installed hydroelectric capacity in Germany with which we generated 5 TWh in 2016. This makes us one of the country’s most significant producers of zero-carbon power from water.4 Climate Change In Sweden, we have a further 1.5 GW of installed hydroelectric capacity. Unlike other renewables, this hydro capacity is flexible. And some hydro assets, called pumped-storage hydroelectric (PSH) stations, can switch quickly between electricity production and storage. They can store energy by using surplus electricity in the grid to pump water into a reservoir at a higher elevation. When energy is needed, the water is released to drive turbines that produce electricity. PSH stations can quickly change how much electricity they produce. This enables them to balance out load fluctuations and regulate grid voltage and frequency. They therefore play a crucial role in ensuring grid stability and in integrating intermittent wind and solar output. They can also be used to jump-start the grid after a widespread outage.

PSH stations have a round-trip energy efficiency of between 70 and 80%. This means that 70 to 80% of the energy used to pump the water higher is recaptured when it falls. They currently represent the only technology capable of efficiently storing large amounts of energy for an extended period.

Availability of Hydro Power Plants (2016)

Hydro power plants
(Operational Management)
Availability of hydro
Germany (run of river, reservoir) 98.3
Unplanned outages1 0.5
Planned outages2 1.2
Sweden (run of river, reservoir) 98.9
Unplanned outages 0.6
Planned outages 0.5
Germany (pumped storage) 85.5
Unplanned outages 7.9
Planned outages 6.6
1Power plants go offline (unplanned) e.g. due to technical defects.
2Power plants go offline (planned) e.g. due to maintenance.

Developing new storage technologies

But PSH stations don’t exist everywhere. So it’s important to develop other technologies that can be deployed in especially sunny or windy regions so that renewable energy can be stored where it’s produced. When electricity production exceeds demand in one grid segment, the surplus has to flow to another. When grid congestion prevents this, wind farms in the first segment often have to curtail their output or even go offline to eliminate the surplus and prevent overload.

That’s why we’re working on transforming surplus renewable power into hydrogen or methane. The technology is called power-to-gas (P2G) or wind gas. The resulting gas can be used for a variety of industrial processes, as a vehicle fuel, and as a fuel for generating power and heat. In particular, methane (known as synthetic natural gas) could be stored in the natural gas system and in underground gas-storage facilities without limitation. We’ve been conducting P2G trials for several years in places such as Falkenhagen in northeast Germany.Climate Change – Falkenhagen

Power-to-power (P2P) battery storage represents another flexible solution. In the past, battery systems were not suitable for large-scale applications. Together with RTWH Aachen University and other partners, we developed a prototype whose hybrid design incorporates five different battery technologies and 25,000 battery cells. In September 2016 we began test operations. The battery can store several megawatts of capacity and is designed to be used in conjunction with on-site renewables production at industrial facilities.

Ensuring a stable energy supply

Our core business is about more than providing flexible reserve capacity. In addition, we generate baseload and intermediate-load power 24/7. Our 38.2 GW of installed capacity (including our capacity in Russia) makes us one of Europe’s largest power producers.

38.2 GW

Installed capacity

138.7bn kWh

Owned generation

31 years

Average age of our gas- and coal-fired power plants


Our planned investments in new coal-fired power plants5

In my view, it’s no longer a question of whether Germany will phase out coal. As for Uniper, we have no intention of building any more coal-fired power plants in Germany. That wouldn’t make environmental or business sense. And if no new plants are built, the end of this technology in Germany is in sight. So it’s now really only a question of how coal will be phased out.

Klaus SchäferChief Executive Officer

Periodic technical upgrades to our assets are crucial for ensuring high rates of availability and efficiency and for preventing unplanned downtime. Most power outages are the result of severe weather or faults in the transmission grid. But a stable energy supply can also be endangered by natural disasters, IT failures, terror attacks, fire, explosions, and political instability. Essential public services depend on our power and gas supply. That’s why, along with safety, preventing supply interruptions is our top priority.


Average availability factor of our fossil-fueled assets


Average availability factor of our hydro assets

Being one of Europe’s leading energy producers means we have a major responsibility to ensure the energy supply. Our generation portfolio contributes to resolving upcoming crises of all kinds swiftly and responsibly. We continually improve and refine all the processes necessary for this purpose, including our integrated Asset Management System. This system enables us to ensure that we operate our assets as cost-effectively and reliably as possible, and without compromising on our safety, health, and environmental performance. The principles of this system are laid down in our Physical Asset Policy and are to be complied with throughout an asset’s life cycle, from planning to dismantling. In addition, we’ve introduced two other management processes that enable us to analyze asset-related risks and market risks could affect our business.

Responsible asset management

We can only ensure the implementation of the principles of our Physical Asset Policy if everyone at our company plays their part. This applies in particular to the employees working at our assets. We have therefore defined responsibilities, processes, and guidelines. These include topics such as work safety, business continuity, and crisis management. Our Chief Operating Officer (COO) is responsible for the effective integration of all these fundamental elements within our Asset Management structure.

Core asset management functions are distributed across three departments: Corporate Security is responsible for the planning framework, guidelines and monitoring measures relating to occupational safety; Process Safety monitors activities in plant and process safety; HSSE Governance & Solutions is responsible for monitoring occupational health and safety.

If a business-critical event occurs, the COO has the authority to form a crisis management team. He is also responsible for creating an organizational structure capable of dealing with any type of crisis situation and ensuring smooth crisis-management processes.

On February 1, 2016, a fire broke out in the boiler house at the GRES TG 3 unit of Berezovskaya power station in Russia, damaging essential components of the 800 MW boiler, which must be replaced. The unit is out of operation while repairs are under way.

Natural gas: partner for wind and solar

Natural gas, whose carbon emissions are relatively low, is the ideal partner for wind and solar energy. Gas-fired power plants are extremely fuel-efficient and can adjust their output within a few minutes, enabling them to balance out the fluctuations in renewables production and ensure grid stability. That’s why natural gas will play a pivotal role in the energy system of the future. We operate gas-fired power plants in several countries.


Gas-fired generating capacity as a percentage of our total capacity

We also procure natural gas and thus make a major contribution to the reliability of Europe’s heat supply. Many European countries’ domestic gas production is insufficient to meet their needs. We help fill these gaps by procuring natural gas from a variety of producers in several countries, mainly Germany, the Netherlands, Norway, and Russia.

In 2016 we procured 407 TWh of gas via long-term contracts. This gives our diversified gas procurement portfolio a solid foundation. In addition, we buy and sell gas on a spot basis at Europe’s trading venues. We sold a total of 1,725.7 TWh of gas in 2016, with 84% going to our wholesale and business customers.

Liquefied natural gas (LNG) is becoming an increasingly important ingredient in Europe’s energy mix. We procure, transport, and market it worldwide. We purchase gas, in addition to the above-mentioned countries, in the form of LNG from Qatar and Algeria and, going forward, the United States and Canada. The Uniper Group has entered into a 20-year contract for the procurement of approximately 800,000 metric tons LNG per year, which are extracted in the United States. LNG arrives in Europe on large tanker ships. After being transformed back into natural gas at special terminals, it’s fed into the pipeline system and used to produce power and heat. But LNG itself can also be used as a climate-friendly alternative fuel for heavy trucks, ships, and locomotives. We operate along the LNG value chain, from procurement and trading to regasification and operating LNG fueling stations in the near future. Our access to the global LNG market allows us to offer comprehensive and competitively priced service bundles to our customers. Nevertheless, there is a basic risk of supply disruption, e.g. for technical production-related reasons or other transit restrictions. As the Uniper Group obtains a large part of its gas supplies from Russia, it is highly exposed to risks in connection with the Russian political situation. At present, the main risks center around the Ukraine conflict.

Furthermore, we support our customers in planning, building, and commissioning gas transport systems and managing gas pipelines, storage facilities, and infrastructure projects. Our own gas storage facilities play a key role in ensuring that consumers have a reliable supply of natural gas in Europe. We operate facilities in Germany, Austria, and the United Kingdom. With 6.8bn cubic meters in Germany, we have more capacity6 than any other operator.

Energy services backed by decades of experience

We use our decades of experience in the energy industry to help shape the future of the energy supply system. We offer customers a broad portfolio of engineering and technical services. We support operators of conventional power plants to increase their assets’ flexibility, availability, and efficiency. We also help wind-farm operators to increase asset availability and to reduce costs.Climate Change

We continually expand our knowledge of how to manage and maintain complex industrial facilities. We also market this knowledge to transport system operators and other companies along the energy value chain interested in optimizing their asset management. We offer custom-tailored solutions in areas such as power plant construction and operations, fuel procurement (coal, natural gas, LNG), energy and commodity trading, and energy marketing.

We believe that tomorrow’s energy world will be based more on partnerships. That’s why we’re deepening our partnerships with large commercial customers and working closely with them to design innovative products and solutions tailored to their specific needs.

We’ve been supplying energy to RW silicium, a producer of metallurgical silicon in southeast Germany, for a long time. The company’s production is so energy-intensive that at times its demand overloads the grid. We recently deepened our business relationship with RW silicium to include demand-side management and flexibility marketing: Uniper experts monitor our customer’s energy use continuously, enabling them to deftly balance supply and demand, and avoid grid overloads. At the grid operator’s request, we can even curtail RW silicium’s production by remote control, thereby reducing its energy consumption by up to 30 MW within five minutes. Such production flexibility helps keep the grid stable. RW silicium receives a reward for its flexibility from the grid operator.

1Figure includes also assets for which we have operational control.
2Plants such as Irshing 5 CCGT, which entered service in 2011.
3Average annual consumption of 4,000 kWh per household.
4List of power plants prepared by Germany’s Federal Network Agency (March 2016).
5Does not include ongoing project in Datteln (completion is planned for the first half of 2018) or maintenance expenses.
6Volume of storable working gas (technical).

Assured Content

Selected figures were independently audited and are identified by the “audited” check symbol   .
Qualitative content related to the Management Approach was also part of the assurance.

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