Marseille’s sea-side detox

Marseille, France

Marseille's strategic position by the Mediterranean Sea comes with key economic opportunities but brings about some challenges as well – notably when it comes to dealing with the summer heat.

heating and cooling

Mitigation

Mission City

As an historical and dynamic coastal city in the Mediterranean Sea, Marseille was always an important hub for trade and is now establishing itself as a cluster for high tech and information-based industry. Its strategic position comes with key economic opportunities but brings about some challenges as well – notably when it comes to dealing with the summer heat.

An approach for Mediterranean cities

Unlike Central and Northern cities, Marseille struggles with cooling the most – namely with the air pollution and emissions by air conditioners, added to the heat island effect they create which the city is striving to eliminate.

Leveraging geographic advantages

Despite the many challenges posed by cooling down Southern European cities amidst rising temperatures, Marseille demonstrates that there are benefits to leverage in addressing these challenges. In this case: the Mediterranean Sea. Marseille is thus using everything at its disposal to decarbonise its heating and cooling simultaneously, investing in an innovative technology – sea thermal energy– to use seawater for cooling as well as heating. There are already two networks (Massileo and Thassalia, combining 4.4 km of pipes) fully powered by the sea, and more are being developed. These networks allow for a decrease of 80% of CO2 emissions in the energy production. Moreover, as a world hub for data centres, Marseille is exploring the recovery of waste heat from these centres.

Rallying around a common goal

For this innovative and ambitious approach to cooling decarbonisation, Marseille needs everyone’s support, including politicians, public agencies, companies and the population as well. Marseille must ensure that all these stakeholders share a common objective, while also gathering the financial support necessary to conduct and assist the thermal renovation of the buildings and the expansion of the innovative heating solutions. In this case, ADEME’s – the French agency for ecological transition - heat fund plays an important role.

Main challenges to detoxify heat:

To deal with the cooling challenges: how to limit air condition and avoid heat islands
To guarantee strong cooperation between different players
To develop thalassothermal energy despite the technical and geographical constraints
Acquire the technical and legal expertise within the city’s administration to develop district heating network projects

Next steps:

Complete the feasibility study for the first public district heating system project and start its construction
Develop district heating network extension projects with other local stakeholders, such as social housing providers
Participate in the development of heating networks powered by renewable energy (thalassothermal, geothermal, solar thermal energies and waste heat recovery) to offer sustainable cooling solutions
Where they are in the heat strategy :

Where Marseille is in its heat strategy

Financing your heat strategy

Budget: 46.2 M€ minimum investment

Sources of funding:

Fond Chaleur (ADEME national fund)
ELENA (European Investment Bank)
Private sector (Energy firms)
Contribution in kind with public lands (City of Marseille)