This is an extract from a recent paper “Green Hydrogen Is Danish Hydrogen” prepared by State Of Green.

In Denmark, hydrogen will be produced using renewable energy sources like wind and solar with zero carbon emissions. This supports Denmark’s commitment to clean energy, decarbonisation, and reaching climate neutrality in 2050. Denmark has a long tradition of active energy policy, initiated as a reaction to the first oil crisis in 1973. Over the years, aggressive pursuit of energy efficiency, system integration, and renewable energy generation has moved Denmark close to a fossil-free energy system.

The next step is decarbonisation of heating, transportation, and industry through both direct and indirect electrification, taking advantage of the high level of renewable energy in the Danish energy system. Hydrogen is the natural conclusion of this journey. It holds considerable potential for reducing CO₂ emissions in hard-to-abate sectors and offers further potential for system integration and deployment of renewable energy sources.

Power-to-X and green hydrogen: Power-to-X (PtX) is a blanket term that refers to a set of technologies that convert renewable electricity into other forms of energy products. The ‘X’ represents different energy carriers or products that can be generated through this process, including hydrogen, e-fuels, chemicals, and materials. In Denmark, the term is used to signal that the product is not necessarily hydrogen; it could also be methane, ammonia, or synthetic fuels.

Today, nearly all hydrogen production is based on fossil fuels such as coal (brown hydrogen) or natural gas (grey hydrogen). Using renewable energy instead of fossil fuels to produce fuels and chemicals can contribute to significant CO₂ emission reductions. In Denmark, the focus is on producing hydrogen and hydrogen derivatives using only renewable energy, making Danish hydrogen exclusively green hydrogen.

The best use of hydrogen: When decarbonising light transport and space heating, direct electrification through battery-powered vehicles, district heating or electric heat pumps is the most cost effective and energy-efficient pathway. Due to their energy losses, e-fuels are more efficient for areas where direct electrification is not possible or is associated with very high costs, such as long-distance flights, freight shipping, industrial high-temperature processes, and energy-intensive vehicles in agriculture and construction.

The Danish principles for using hydrogen: Firstly, hydrogen production should be based on renewable electricity and should be fully integrated into the energy system. Secondly, hydrogen and hydrogen derivatives should only be used when direct electrification is not feasible. Thirdly, the development of the sector should be based on market terms. Finally, sectoral integration is key for the success of full deployment by, for example, utilising excess heat from electrolysis in the district heating system or using sources other than drinking water for electrolysis to create a circular process that protects drinking resources.

Green Hydrogen Value Chain

Green hydrogen value chain from a Danish perspective where the energy source is derived from renewable sources like wind and solar. Hydrogen functions as an energy carrier, crucial for balancing the energy system, and is transported through pipelines and stored in underground salt caverns. Additionally, hydrogen serves as a building block for hydrogen-based products, where hydrogen can be combined with either nitrogen for e-ammonia or carbon dioxide for e-methanol and e-kerosene. The Danish approach sees sectoral integration as key for the success of the full deployment of green hydrogen. This includes utilising excess heat from electrolysis in the district heating system and purifying wastewater for electrolysis.

Political framework to support an emerging green sector

With an ambitious political framework Denmark aims to become a frontrunner of green hydrogen. The 2022 Agreement on green hydrogen and green fuels sets a goal of 4-6 GW electrolyser capacity in 2030 and defines economic subsidies to kick-start the sector. Green hydrogen plays an important part in fulfilling the 2020 Danish Climate Act’s goal to decarbonise Danish society by 2050. As such, the Danish parliament has agreed ambitious targets for the roll-out of PtX in Denmark.

The PtX agreement builds on the visionary 2020 Climate Act and sets the ambition for Denmark to become a frontrunner in the production of green hydrogen. The agreement sets a target for building 4-6 GW of electrolyser capacity in 2030 with the goal to further Danish participation in the emerging European hydrogen market. It is a principle for the Danish approach that the roll-out of hydrogen and hydrogen derivatives should be market-based.

To kick-start the emerging hydrogen economy, the Danish state has initiated a tender to subsidise the production of green hydrogen, awarding DKK 1.25 billion towards the end of 2023 to green hydrogen producers. The purpose of the tender is to support the industrialisation and scaling of Danish hydrogen production and price discovery. Since 2019, more than DKK 3 billion of public funding has been allocated to support the Danish hydrogen sector.

The Power-to-X-taskforce, which is anchored in the Danish Energy Agency, was also established to ensure smooth cooperation between government, municipalities, and private stakeholders, and to help identify and clear barriers to allow the growth of the Danish hydrogen sector.

The roll-out and success of the Danish hydrogen adventure hinges on an extensive planned build-out of renewable energy, mostly from North Sea wind farms. To ensure consistent efficiency, the Danish government allows for overplanting of offshore wind turbines.

The Danish government is working to ensure a framework that can accommodate smart regulation and cost-effective differentiated grid tariffs that can reward flexibility and interrupt ability to ensure that green hydrogen production is integrated in the national electricity grid, which will be dominated by wind and solar power in the future.

Towards 100% renewable electricity production

Denmark is at the forefront of wind power and the integration of variable renewables. Abundant wind resources combined with hydrogen and hydrogen derivatives can secure a reliable, independent, and sustainable net-zero emissions energy system. Highly dependent on imported energy, the 1970s oil crisis led to increased electricity costs in Denmark.

The Danish wind power legacy: Despite renewables originally being more expensive than fossil fuels, continuous political commitment secured more and larger wind power projects onshore, and in 1991 Denmark established the world’s first offshore wind farm, Vindeby. Since then, the increasing scale of offshore wind and strong technological improvements from the Danish wind power industry have reduced costs throughout the whole supply chain — producing a lower Levelised Cost of Energy (LCOE) and increasing the competitiveness of offshore wind. Today, renewables are among the cheapest forms of electricity production in Denmarkand many other countries around the world, and costs are expected to further decrease as scale increases.

Gigantic potential for offshore wind: Geographically located between the North Sea and the Baltic Sea, Denmark has access to abundant offshore wind resources which provide the potential for Denmark to become Europe’s green powerhouse. With the Ostend Declaration, European politicians have set the ambitious target of 120 GW offshore wind capacity by 2030 in the North Sea, with the potential to increase capacity to at least 300 GW by 2050. Denmark can deliver a substantial amount of this.

Strong grid and flexibility from electrolysers: With a security of electricity supply of 99.99 percent, the Danish energy system has proven that it is possible to integrate large amounts of intermittent renewables. In the coming years, the need for a continued build-out of the electricity grid, as well as hydrogen pipelines across Denmark and to neighbouring countries, will grow as the volumes of intermittent, decentralised electricity production increase. Electrolysers will play a key role in securing the balance between electricity supply and demand. Renewable electricity and electrolysers thereby benefit each other towards securing the value creation and competitiveness of Danish renewables and hydrogen production.

From pioneering wind to pioneering net-zero energy systems: The potential for offshore wind energy in Denmark is high. Combined with hydrogen, Denmark can secure a reliable, independent, and sustainable net-zero emissions energy system. Denmark has a history of pioneering achievements, particularly in the refinement of skills within wind energy. Presently, the nation is poised to undertake a new pioneering initiative, with a specific emphasis on hydrogen.

Electrolysis: the next phase of the green transition

An electrolyser is a device that uses electricity to split water into oxygen gas and hydrogen gas. To keep the gases separate and prevent mixing, there is a special membrane in between called an electrolyte. It helps to balance the charges and keeps the gases from getting mixed up or contaminated. When using renewable energy for electrolysis the hydrogen produced is called green hydrogen.

Old technology given new life: There is nothing new about producing hydrogen from wind power — in Denmark, at least. Back in 1894, the inventor Poul la Cour used electricity from a wind turbine to split water into oxygen and hydrogen gas. The gases were separately collected in tanks, stored in bottles, and used to light buildings, such as the Askov Folk High School.

How green hydrogen can be utilised: While producing green hydrogen through electrolysis is not a new technology, the hydrogen currently used in industrial processes is predominantly fossil-based, being derived from gas and coal. Today’s hydrogen supply accounts for 1.7 percent of the global annual energy consumption and emits 830 million tonnes of CO₂ annually. Only about 1 percent is based on renewable energy. As global renewable energy continues to grow rapidly, the potential for substituting fossil-based hydrogen with green hydrogen represents vast opportunities for emissions reductions. Green hydrogen can be utilised in many parts of the energy system, either in its pure form or as a building block in further refining processes. As a fuel, green hydrogen is completely free of harmful emissions; a vehicle fuelled by hydrogen, for example, only emits water vapour.

The importance of water: Danish efforts to develop suitable solutions for electrolysis focus on purifying wastewater, and using groundwater from areas where the water level is problematically high and cannot be used for consumption. In this way, electrolyser plants can contribute to a new water ecosystem which uses low-quality water from other sectors, including wastewater from private households. While technologies within wastewater treatment and water purification already exist in Denmark, the Danish water industry is also working on new technologies to solve these challenges.

Cross-sector collaboration: Collaboration across sectors is a longstanding Danish tradition. Whether between industry actors, research institutes, and private businesses, or public-private initiatives to solve the greatest challenges facing society, cooperation lies at the heart of the efforts driving positive developments.

Connecting the Danish hydrogen sector to Europe

Establishing a Danish pipeline infrastructure for hydrogen will ensure a cost-effective, large-scale, and steady distribution of green hydrogen to users in both Denmark and Europe. To ensure that the vast amounts of Danish-produced green hydrogen make it from producers to users, efficient means of transportation will be necessary. Initially, while the sector is still developing, hydrogen can be transported on trucks and ships. However, with the rapid scale-up of hydrogen projects throughout Denmark, pipeline infrastructure will be the cheapest, and for larger projects the only viable means of transportation.

Hydrogen infrastructure in Denmark: The Danish government is leading the way by working towards establishing the necessary framework for a market-based roll-out of hydrogen infrastructure. Recently, the government reached an agreement that ensures public ownership and operation of future hydrogen infrastructure in Denmark. The two state-owned gas system operators, Energinet and Evida, will build and operate the infrastructure based on the market demand for pipelines. Energinet will connect cross-border hydrogen infrastructure, offshore infrastructure, and cross-border pipelines across Denmark to a storage facility. Evida will connect national hydrogen producers and users to the interconnected Danish hydrogen system.

Hydrogen can solve the challenge of renewable energy storage: Hydrogen pipelines have an inherent capability to serve as storage by pressuring the pipeline. Additionally, parts of the Danish underground have unique properties which can be utilised to store hydrogen. Today, large natural underground chambers known as salt caverns are used to store pressurised methane gas. As the demand for natural gas decreases, the possibility for storing hydrogen could become relevant. Such large-scale storage would offer possibilities for flexible operation of electrolysers in coordination with electricity markets, while ensuring a stable, continuous supply of hydrogen to Danish consumers, producers of e-fuels, and neighbouring countries.

Regional interconnection of infrastructure: Hydrogen distribution plays a major part in ensuring a green future for Denmark as well as its neighbours. A border-crossing infrastructure along with Danish renewable energy resources will allow Denmark to export green hydrogen across Europe. The REPowerEU plan — with its target of 10 million tonnes of domestic hydrogen production and a further 10 million tonnes in imports by 2030 — highlights the need for an efficient infrastructure network across borders.

Access the report here