Wind energy: Wind turbines convert wind into renewable energy in the form of electricity. Hydropower: Water that flows in a river or is collected behind a dam produces renewable energy in the form of electricity by flowing through a water turbine. Solar energy: Solar cells and solar panels convert the rays of the sun into renewable energy in the form of electricity and heating. Biomass: Biomass is converted into electricity by combustion. Biomass, organic waste, and manure are converted into biogas, which is supplied to, for example, the natural gas network. Biogas plants: Biogas is formed in biogas plants when biowaste is decomposed by bacteria in an oxygen-poor environment. In addition, biomass like wood pellets and wood chips is converted into biogas at gasification plants. Biogas can be used in the production of green fuels. Heat production: Heat pumps will gradually replace fossil-based heat production and effectively convert electricity from the electricity grid into heat. The heat pumps are placed at individual consumers or in the district heating systems in Denmark, which—via underground insulated pipes—supply heating to households and industry. Heating: District heating systems consist of low-temperature solutions where you can return excess heat back to the grid. In a modern system with well-insulated houses and floor heating, you can use a low temperature in the district heating system and still heat the home. The advantage of the low temperatures is that less heat is wasted. Electricity: A nationwide transmission grid is connected to local distribution grids, which ensures that households and companies are continuously supplied with power. Intelligent management and monitoring of the electricity grid ensure that there are no power outages and that there is balance between production and consumption. Power-to-X: Electricity is converted to hydrogen and other green fuels for industrial use or for heavy goods transport—for example by air and sea—where electricity cannot be used directly. Hydrogen production can be done using Power-to-X technologies. Here, a so-called electrolysis process ensures that water can be split into hydrogen and oxygen. In other Power-to-X technologies, hydrogen can be refined into ammonia and methane. The green fuels can be stored and used when the wind is not blowing and the sun is not shining. The gas grid is used to transport biogas and green hydrogen. The digital consumer: All elements of the energy system are managed through markets and digital controls that communicate with each other. By means of digitalization, data can be collected and the energy system can be optimized, thus preventing fluctuations and power failures. For private consumers, digitalization means that—via your smartphone—you can check your electricity, water, and heating consumption, enter into agreements about your energy consumption, and state your preferences. Consumers may consume, produce, and store energy, as so-called prosumers. Consumers play an active role in the energy system and can, for example, form part of local energy communities with purchases and sales of local green power to the surrounding houses. The intelligent infrastructure: The energy system of the future is a sustainable system in which renewable energy generation, infrastructure, and energy consumption are integrated through energy services, active users, and technologies. The system consists of types of energy with fluctuating production that are much more unstable than conventional energy sources. This means that it is necessary both to maintain the current security of supply and ensure energy supply stability. In order to balance production and consumption, we therefore need digitalized energy systems and new technologies that can be controlled by, for example, artificial intelligence. This presupposes integrated interaction between the various energy sectors. Transport: Heavy goods transport such as ships, aircraft, and trucks cover long distances can refuel green fuels at refuelling facilities in ports and airports – or from energy islands at sea. Buses and vans are supplied with electricity from recharging points. Homes: Homes are supplied with 100 per cent green, renewable energy. Homes will have an integrated charger for electric cars. The electric car is programmed automatically to recharge when there is a lot of energy on the market and the electricity price is low. This will especially be at night and when the wind is blowing. Industry: Large companies and agriculture will—like private consumers—be supplied with 100 per cent renewable energy. At the same time, they return their production surplus heat to the district heating network, so that the energy is not lost, but is reused, for example for heating of private households. So-called biogenic CO2 can also be utilized from companies and energy plants that use biological materials. This may—for example—be wood and organic food waste containing CO2 absorbed from the atmosphere during the life cycle of the materials. Together with hydrogen, CO2 can be utilized to develop Power-to-X fuels.

Illustration: Claus Lunau