An ambitious new project led by Carlo Ratti Associati (CRA) could provide Helsinki with a sustainable heat source and in addition serve as an attractive location for Finns to escape the long harsh Scandinavian winter. The architect's plans, called Hot Heart, include several artificial islands that will store thermal energy and use some of that heat to create a tropical paradise.
If the project goes ahead, Hot Heart will be located off the coast of Helsinki and consist of an archipelago of 10 artificial islands that can be seen as huge water basins. Each island will be 225 m in diameter and contain up to 10 million cubic metres of water.
Thermal battery
According to CRA, the system will work as a large thermal battery. Using seawater heat pumps, energy from wind, solar and other renewable sources will be converted into heat that will be stored as hot water in tanks. This can then also be extracted and pumped back into the district heat network. According to CRA, the system will start from existing renewable energy sources. As the number of solar panels and wind turbines in the country increases, the system will be adapted accordingly so that eventually Helsinki's entire heating needs can be met.
Moreover, thanks to all the heat produced, four of the islands will be able to serve as recreational destinations, with swimming pools and tropical forests and plants. They are planned to be enveloped in a transparent dome and LED lighting, so that locals can also escape the winter cold from time to time.
Artificial intelligence
Producing renewable energy is becoming cheaper and cheaper, but storing it is still very expensive. By developing giant 'thermal batteries', energy can be stored when prices are low, for example during the day when the sun is shining or a brisk breeze, and reused when the district heating system demands it. To develop the concept, CRA collaborated with an international group of consulting and production companies and energy optimisation experts. The entire system of seawater heat pumps, wind, solar and other forms of energy is controlled by artificial intelligence. In this way, production and consumption of thermal energy are synchronised. The entire system is expected to cover Helsinki's entire heating needs, estimated at 6,000 GWh, by the end of the decade. CO2 emissions are thus off the table while the cost of energy is estimated to be 10 per cent lower than today. Although Hot Heart is only in its infancy, it recently won the Helsinki Energy Challenge competition. CRA hopes it will be realised by 2028. A similar idea is already being worked on elsewhere in Scandinavia, by the way. Similar alternatives are also being worked on in Denmark.
