By Mads Sejer Nielsen, AAU Communication and Public Affairs.
Translated by LeeAnn Iovanni, AAU Communication and Public Affairs.
Foto: Birgitte Bak-Jensen.

In a comprehensive energy project, AAU researchers in conjunction with 21 partners have developed solutions for CO2 reduction with local energy systems through optimal, smart integration of renewable energy technologies like heat pumps, solar cells and wind turbines.

"By integrating technological solutions with social, regulatory and environmental considerations, we have created a reusable framework for sustainable energy systems that improves the quality of life globally," says Birgitte Bak-Jensen, Professor of Energy at Aalborg University and coordinator on the project.

For four years, the researchers tested how to optimize energy management locally in, for example, a village or a residential neighbourhood, without overloading the electricity grid, and how to generally become more energy efficient by using local options like a wind turbine or solar cells.

The results are clear: If you want to effectively reduce CO2 at the local and national level, this requires more flexibility and less legal complexity – especially in Denmark.

"Denmark has implemented the EU energy rules in such a way that the general public cannot share their electricity from sources like solar cells without creating a company that supplies electricity. This is not very useful because the rules are very complex. If you really have ambitions to reduce CO2 and at the same time create smarter energy solutions in outlying areas, then you need to look at the rules, because right now they are an obstacle for the many small communities that could benefit," says Birgitte Bak-Jensen.

The conversion from gas or oil furnaces in particular make for CO2 savings. The project showed that 20 households with gas heating can go from emissions of 120 tonnes of CO2 per year to approximately 62.8 tonnes per year if they switch to using solar cells and heat pumps for electricity and heat.

This corresponds to 2.86 tonnes of CO2 savings per household.

In addition, investments in a heat pump can pay off over four to five years as the switch from oil or gas boilers will save an average of DKK 20,000 per year.

And this is necessary because the electricity grid and the district heating network cannot keep up with developments everywhere in the country without it being expensive for taxpayers.

Energy optimization is a prerequisite for saving money

The challenges in Denmark in particular are evident in the peak load of the electricity grid. In recent years, many Danes have opted for an electric car, and then people want to refuel when electricity is cheapest. But if everyone chooses to charge their electric car at two in the morning, when electricity is cheapest, then the electricity grid won’t be able to keep up in the long run – unless we make massive investments in an upgrade.

So, solutions are required that are more flexible for the general public, so that they can, for example, use cheap electricity from a local heat pump, solar cell system or wind turbine at other times.

"If we get the large electrification that is taking place now in Denmark under better control, then the electricity grid will be able to withstand the load without huge investments. But, the rules must be changed because as things stand now they are simply not good enough. That’s why we have also outlined suggestions for politicians – not only in Europe but also in Denmark," says Birgitte Bak-Jensen.

The solutions were verified at six demonstration sites – three in the EU and three different sites in India. These demonstration sites in Denmark, the Netherlands, Poland and India provide real-world examples showing how societies with different economic, societal and political contexts can effectively apply the solutions found.

The SUSTENANCE project was funded by the EU Horizon 2020 programme and India's Department for Science and Technology (DST), and brought together 21 partners from three European countries and India. The project was coordinated by Aalborg University in Denmark and the Indian Institute of Technology Bombay (IITB) in India.