How about we explore Avedøre Power Station? This combined heat and power station stands south of Copenhagen. It is owned by Ørsted A/S. Avedøre Power Plant is a high-tech facility. It is one of the world’s most efficient of its kind. The plant can utilize as much as 94% of the energy in the fuel. It converts 49% of the fuel energy into electricity.
Avedøre Power Station’s design comes from architects Claus Bjarrum and Jørgen Hauxner. Its presence is a monument on the city’s skyline. The plant consists of two units. Together they generate 793 MW of electricity and 918 MW of heat.
Unit 1 is the oldest unit. It was built in 1990. Coal was its primary fuel. Oil can also be used. Avedøre Unit 1 achieved an energy conversion efficiency of up to 91%. This happened by using excess heat for district heating. This made it one of the world’s most efficient coal-fired power plants. As of 2015 it was being converted from coal to wood pellets. The cost was DKK 740 million. It burns 1.2 million tonnes of wood pellets per year. This reduces CO2 emissions by about a million tonnes.
Unit 2 is the newest and most efficient. It was built in 2001. It burns various fuels like natural gas and heavy fuel oil. It can also burn straw and wood pellets in the same burners. Avedøre Unit 2 has a production capacity of 585 MW of electricity. It generates 570 MW of heat. It is the most efficient of the two units.
Avedøre Unit 2 also consists of multiple sub-units. The main sub-unit is the 80 metres super critical boiler. It links to a steam turbine and an electrical generator. One of the world’s biggest biomass boilers connects in parallel to the turbine. Unit 2 also has two separate gas turbines. Each has a capacity of 110 MW.
Avedøre Unit 2 has an electrical efficiency of 49%. This makes it one of the world’s most efficient. This high efficiency occurs when the unit only produces electricity. The electrical efficiency decreases when producing heat for district heating. The heat exchange occurs at a higher temperature then. When factoring in the heat energy exported to district heating the energy conversion efficiency reaches 94-96%. This makes it one of the world’s most efficient combined heat and power stations. In preparation for conversion to 100% biomass in 2027 the plant received a 360 tonne crane. It can transfer 800 tonnes of wood pellets per hour from ship to shore.
As a by-product high quality plaster is made. This happens when cleaning the flue gas. Avedøre Power Station supplies 200000 households with heat. It generates about 30 % of the electricity consumption on Zealand. This equals the annual electricity consumption of around 1.3 million households.