Baltic Cable is a key part of the infrastructure that links together Europe’s electricity grids. It is a 250 km long high-voltage direct current (HVDC) submarine cable that transmits electricity between the converter stations outside Trelleborg, Sweden, and Lübeck, Germany. There are several interconnections between Sweden and other countries in the form of submarine cables, most of which are partly owned by Svenska kraftnät. Baltic Cable is currently the only interconnector between Germany and Sweden. 

Since 2010, Baltic Cable AB is a wholly owned subsidiary of the Norwegian state-owned company Statkraft. 

Baltic Cable is certified in Germany as a TSO under the ITO unbundling model, which sets strict requirements for the separation between the activities of Baltic Cable AB and Statkraft Group. This entails that Statkraft Group has no direct or indirect influence on, or insights into, the day-to-day business of Baltic Cable AB or the operation of the Baltic Cable interconnector. 

Baltic Cable earns its income from congestion rents, which arise when electricity prices differ between the two bidding zones connected by our submarine power cable. Unlike many other grid operators, Baltic Cable does not charge network tariffs or other customer fees. Our role is to make transmission capacity available to the market through the interconnector between Sweden and Germany. We do not determine how much electricity is transmitted or in which direction it flows. 

Electricity flows are determined by EUPHEMIA, the algorithm used by European power exchanges to match supply and demand across countries while making the most efficient use of available transmission capacity. Based on market conditions and price differences between bidding zones, the algorithm calculates both electricity prices and cross-border power flows.

Baltic Cable has no authority to influence these outcomes. Our role is limited to providing transmission capacity and operating the interconnector. The resulting congestion rents are collected and used in accordance with the regulatory framework to cover operating and capital costs and to provide a reasonable return. 

Baltic Cable receives congestion revenues/income when the cable is in use. How the company may use these revenues to cover operating costs, investments, and make a reasonable return is regulated by the regulatory authority. This means that the regulator determines how much profit Baltic Cable may make, in a similar way to how Sweden’s power grids are regulated. This allowance does not change even if congestion income/revenues increase. The company does not have free access to all congestion revenues.  

Ultimately, EU law governs how the electricity market in the EU must function. Baltic Cable AB is classified as a TSO (Transmission System Operator) just like the connecting parties Svenska kraftnät and Tennet TSO GmbH. However, Baltic Cable does not apply tariffs, as it does not have any customers. 

Baltic Cable has a nominal interconnection capacity of 615 MW and operates at 450 kV and 1364 A, with a minimum flow of 50 MW. As opposed to the majority of the electricity network including household connections, it operates at direct current (DC), meaning that the electric current flows in only one direction with a constant polarity.  

The capacity is adjusted with a certain delay, with a power change rate of 30 MW per minute. As with all cables, some losses occur during transmission. The HVDC technology allows for relatively low losses, with approximately 2.4 percent with the converter stations included.  The cable is a double-armoured, single-core submarine cable with a total length of 250 km.  

Baltic Cable is more than a power cable between Sweden and Germany. It symbolizes the cooperation, flexibility and resilience that form the European energy system – where electricity flows across borders to where it is needed most. Electricity is essential for society to function. From healthcare, transport and communication systems to industry, digital services and everyday life. A robust and interconnected power system makes Sweden and Europe less vulnerable in times of crisis, capacity shortages or geopolitical uncertainty. 

Interconnections like Baltic Cable help strengthen this resilience by connecting markets and enabling electricity to flow where it is needed. Cross-border connections help reduce costs, improve price stability and create a more efficient electricity market for both households and industry.  

Most of the time, electricity is exported through Baltic Cable from Sweden to Germany, but the exchange goes both ways. As Germany expands its renewable energy production, Sweden increasingly benefits from imports during periods of high wind and solar generation. During period of high demand, such as very cold winters, Baltic Cable helps strengthen security of supply providing access to electricity from the continent.  
 
During periods of high production in Sweden, Baltic Cables helps move electricity to where it is needed most, reducing bottlenecks and supporting a more balanced use of the system. This helps balance the power system, reduce waste and make better use of renewable electricity. 

In short, Baltic Cable contributes to the kind of energy system Europe needs: secure, flexible and connected. 

If Baltic Cable for any reason ceased to operate, the lost capacity would need to be replaced immediately. Production and/or consumption in the balancing markets of Germany, Sweden, and/or neighbouring countries would be redispatched at once to compensate. 

In the longer term, the electricity market would need to adapt to new conditions, affecting the use of transmission capacities across the region and, in turn, influencing prices. The Nordics would still be connected to continental Europe through a great number of interconnectors between Norway/Sweden/Denmark/Finland and Great Britain/Netherlands/Germany/Poland/Estonia/Lithuania, which in turn are connected to the rest of Europe. Therefore, energy would still flow, at least indirectly, also between Germany and Sweden. The overall capability of the common market to integrate different parts of Europe would weaken and during times with strained energy systems either in Sweden, Germany or some other connected country, the capacity available to remedy such challenges would be scarcer.  

Baltic Cable is built on one of the EU’s core principles: the internal market for trade and exchange between member states. Electricity trading occurs in both directions, facilitating more efficient energy production, contributing to a secure power supply and reducing the risk of disconnection. Both Germany and Sweden rely on trade and cooperation between European countries – including in energy. Ultimately, all consumers benefit from a well-functioning EU energy market.