Carlo Ratti Associati’s Hot Heart for the city of Helsinki
Helsinki is one of the world capitals most active in fighting climate change, aspiring to achieve zero CO2 emissions by 2030. The search for green solutions for the near future has become an international “energy” challenge. The path toward carbon-neutral cities inevitably requires a new form of heating, the principal source accounting for more than half of all urban CO2 emissions.
The Helsinki Energy Challenge is an international challenge launched by the Helsinki city government which recently concluded with the announcement of four winning projects among the ten finalists selected by an international panel of judges. The four winners present different approaches and represent solutions adoptable not only in Helsinki but in other cities with a view to achieving sustainability and innovation in heating systems.
One of the four challenge winners, Hot Heart, was created by a transdisciplinary team coordinated by international architecture, design and innovation studio CRA-Carlo Ratti Associati in partnership with Ramboll, Transsolar, Danfoss Leanheat®, Schneider Electric, OP Financial Group, schlaich bergermann partner and Squint/Opera.
The project is based on a series of islands with a twin function to be built off the Helsinki coast: an idea that can be replicated in other coastal cities with a climate similar to that of the Finnish capital.
Hot Heart is an archipelago of ten cylindrical basins each measuring 225 metres in diameter, and will be the biggest infrastructure of its kind. Together, the ten basins will be able to contain up to ten million cubic metres of water, acting as a big thermal battery. Energy from renewable sources is acquired when the cost of energy is low or even negative, converted into heat and stored in the reservoirs before being transferred to thermal energy distribution channels and restored to the city in winter, when demand is high. At the same time, these “islands” will become hubs for recreational activities. Four of the ten reservoirs of hot water will be enclosed by transparent domes which can contain tropical forests and ecosystems from all over the world. These “Floating Forests” will be naturally heated by the basins of hot water below them, providing a habitat for plant species typical of the tropical rainforest. Thus the city will have new public spaces with an educational purpose, where people can gather even in the rigid Nordic winter to enjoy warmth and light similar to sunlight from new-generation LEDs with a natural light spectrum.
The entire system will be managed by artificial intelligence, and the designers estimate it will be able to heat the entire city of Helsinki with no carbon emissions, at a cost of 10% less than the current cost.
Images courtesy of CRA-Carlo Ratti Associati
An international collaboration for the Helsinki Energy Challenge developed by the teams below:
CRA-Carlo Ratti Associati (Design)
Ramboll (General Engineering) – Mika Kovanen, Kreetta Manninen
Transsolar (Climate Engineering) – Monika Schulz, Thomas Auerv
Danfoss Leanheat® (Demand Management Engineering) – Oddgeir Gudmundsson, Jukka Aho, Juho Nermes, Lauri Leppä, Nico Klecka
Schneider Electric (Technology Partner for Sustainability and Energy Efficiency) – Jani Vahvanen
OP Financial Group (Financial Analysis)
schlaich bergermann partner (Lightweight Structural Engineering) – Mike Schlaich, Boris Reyher
Squint/Opera (Communications Partner)
CRA team: Carlo Ratti, James Schrader (Project Manager), Alberto Benetti, Federica Busani, Rui Guan, Stephanie Lee, Juan Carlos Romero and Chenyu Xu
Renderings by CRA graphic team: Gary di Silvio, Pasquale Milieri, Gianluca Zimbardi
Video by Squint/Opera