Seasonal electricity storage

Stockholm CSP challenge

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This challenge is in partnership with the C40 Zero Carbon Districts Forum.

Read the workshop report here.




In 2008, Stockholm City Council appointed Stockholm Royal Seaport as the next environmentally profiled city district and model for sustainable urban planning. The goal is that Stockholm Royal Seaport will be a fossil-fuel-free city district with low resource use and a high degree of circularity. During the bright summer days with up to 18 hours of sunshine, solar electricity can potentially cover the annual property electricity demand. In addition there is a city-wide challenge of cutting peak loads that occur, especially during cold winter days, that could be addressed by local storage. The City initiated pre-feasibility studies to explore the potential of designing a fossil fuel free energy system for the last neighbourhood to be built, accommodating between 4,000-6,000 households. The pre-planning process has just begun, but decisions on decentralised energy systems will have to be made within the next two years. The design process for the infrastructure will begin 2021/22 with construction starting earliest by 2023.

The challenge is to provide a storage system combining seasonal storage of electricity with a back-up of short-time storage for cutting peak-loads. Seasonal storage solutions should have a capacity of up to 6 months for 1GWh locally generated electricity. Short-time storage should have a capacity of up to 7 days for an additional 20 MWh. The decentralised system should be cost-effective, durable, reliable, low maintenance and replicable. Technical solutions should be produced in a socially sustainable way.

The CSP was a key influencing factor in forming strategic relationships and partnerships post-workshop

City of Sydney

The CSP gave a kick-start to a new strategy for flood management in the city

City of Melbourne

C40 and the CSP are very good at gathering specialist people interested in technology development

City of Rio de Janerio

The CSP helped us fundamentally rethink how we engage the private sector and establish a framework for collaborative innovation

City of Seattle

C40 and the CSP are very good at gathering specialist people interested in technology development

City of Rio de Janeiro

The CSP has helped catalyse investment to bring new ideas further forward

City of Sydney

The C40 CSP event provided a perfect platform for us to do a pre-launch for our very ambitious and globally relevant challenge

City of Helsinki

The Municipality is thankful for the CSP framework which promoted the city towards the targets of the Climate Action Plan

City of Tel Aviv-Yafo

The participation in the City Solutions Platform Live event proved to be a valuable opportunity to engage with both internal and external stakeholders on how the City of Copenhagens food procurement can support a reduction of emissions related to public meals

City of Copenhagen

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