Coal to biomass conversion: Amager plant

Full conversion of Amager power plant in Denmark from coal to biomass, supporting the Danish capital's carbon neutral goals. We provided full spectrum consultancy across the project life cycle.
BIO4 bioconverted power plant in Copenhagen

The City of Copenhagen aims to become the world’s first carbon-neutral capital. Greater Copenhagen utility HOFOR is supporting the city achieve this goal through several initiatives, including the conversion of Amager power plant from fossil fuels to biomass.

Amager power plant consists of two units: One from 1971, which was converted to wood pellets in 2010, and another which ran on coal until it was replaced in 2020 by a new unit, BOI4, which runs on sustainable wood chips.

All power and heat generation at the plant is now based on renewable energy. The conversion to biomass has resulted in CO2 reductions of one million tonnes per year, corresponding to the emissions from 500,000 cars, and has made more than 80% of the district heating supply in the Danish capital carbon neutral.

Ramboll played a significant role in the implementation of BIO4 with a team of experts that were able to take the project from A to Z. Our experts had many important positions in the project, including construction manager, commissioning manager and quality assurance and quality control manager. Ramboll also provided consultancy on the turbine, biomass storage, balance of plant, electrical systems, distributed control system, risk calculations (HAZOP), 2D and 3D computer-aided design, the new office building, site operation, site supervision, operation and maintenance, and health, safety, and environment on site.

Best-in-class energy efficiency

In addition to providing green energy to the Copenhagen area, BIO4 is highly flexible. When the supply of wind energy is high or the demand for heat is high, the plant can generate heat only – up to 585 MJ per second. When there is a demand for power too, the plant can generate both heat and power. BIO4 supplies approximately 25% of the heat demand in Copenhagen.

The new unit has an energy efficiency of more than 110%, which is up to 30% higher than the efficiency of the old coal-fired plant. This energy efficiency, which is best in class compared to other combined heat and power plants, is made possible by utilising flue gas condensation.

The plant was ready for operation at the end of 2020.

Facts about BIO4

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    BIO4 is flexible, generating both power and heat or heat only, depending on demand

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    The boiler is based on circulating fluidised bed technology

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    The plant uses flue gas cleaning with flue gas condensation and has two contained facilities for storage of wood chips and conveyors

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    At full load, BIO4 has a capacity of 185 tonnes of wood chips per hour. Annually, the plant consumes 1.2 million tonnes of sustainable wood chips

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    BIO4 is a green landmark for the city of Copenhagen and a recreational area for the citizens and tourists. In the future, access will be allowed on the plant premises, giving visitors a chance to enjoy the view from a height of 40 metres.

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