A world first renewable energy system inaugurated in Denmark

The vision to set new standards for cost-competitive renewable heat and power production has became a reality with the official opening of a revolutionary green energy facility in Denmark. Inaugurated by the Danish Minister of Energy, Utilities and Climate, Mr. Lars Christian Lilleholt, the 45 million € investment is now ready to produce both sustainable power and heat with the help of an advanced solar energy system from Danish renewable energy specialist, Aalborg CSP A/S.

Replacing natural gas with renewable energy sources is a natural step in Denmark’s green energy transition where most district heating plants typically switch to solar or biomass. However, combining several energy technologies to produce both heat and power is certainly a proof of innovative thinking which recently led to the realization of an ambitious green energy project in the town of Brønderslev.

The system is the first combined heat and power (CHP) plant in Denmark, but also in the whole world to integrate concentrated solar power (CSP) and a biomass boiler while also using Organic Rankine Cycle (ORC) to turn the energy into district heating and electricity. Utilizing benefits of these innovative technologies enables the Brønderslev Forsyning district heating plant to achieve record energy efficiency, lower energy prices and a future-proof solution that is no longer dependent on fluctuating fossil fuel prices. Clean energy also means the reduction of more than 25,000 CO2 annually.

CSP, a flexible energy technology

Part of the new, sustainable CHP facility is an advanced, 26,929 m2 solar energy plant from Aalborg CSP. This solar-thermal system is based on the concentrated solar power (CSP) technology that has already been producing heat since the end of 2016. With the ORC and biomass units also going online, it is now ready to contribute to electricity production as well.

The CSP technology consists of 40 rows x 125m U-shaped mirrors that collect the sunrays throughout the day and reflect them onto a receiver pipe. This receiver pipe is surrounded by a special glass vacuum tube and inside this runs – only heated by the sun – thermal oil with temperatures up to 330 °C. This high temperature is able to drive an electric turbine to produce electricity, but the flexibility of the system also allows production of lower temperatures for district heating purposes. The solar heating system can thus alternate between providing combined heat and power at peak price periods, or exclusively deliver heat. On sunny days, the solar-thermal system in Brønderslev is set to reach 16.6 MWth capacity.

The CSP technology is capable of supporting the production of pretty much any energy outputs, be it heat, electricity, cooling, process steam or even desalinated water.

The achievement of the world’s first CSP system combined with a biomass-ORC plant was supported by the Danish Government’s Energy Technology Development and Demonstration Programme (EUDP).

Source: Aalborg CSP A/S