Stockholm Royal Seaport

Sustainability Report

Energy and climate

Stockholm Royal Seaport will be a fossil-free, climate-positive district, and this permeates all aspects of planning and construction. New working methods, technologies, and business models, in combination with behavioural changes, can contribute to minimising energy use based on renewables.

2022 Highlight:

Climate-improved concrete

Concrete has a significant climate impact, primarily due to its binding agent being cement. In a temporary pile deck for the Lidingö Line, concrete is being tested in which a proportion of the cement is being replaced with blast furnace slag, a by-product of steel production. The test will be monitored over several years to evaluate its technical properties. In 2023, tests will be conducted with climate-improved underwater concrete in conjunction with the development of Saltkajen.

Key figures:

  • All new buildings are low-energy buildings.
  • 895 MWh of solar energy was produced locally in 2022.
  • 44% of fuel used for construction machinery and vehicles in construction projects in 2022 was renewable.
  • The plus-energy buildings in Brofästet have measured values of 12.3 kWh/m² (BBR24).
  • On average, Norra 2 is at 67 kWh/m² (66 kWh/m² according to BBR19 and 20) and Brofästet at 65 kWh/m² (54.5 according to BBR23 and ).

A fossil-fuel free district with low resource use

The City of Stockholm has set a goal to be climate positive by 2030 and fossil-free by 2040. The goal of Stockholm Royal Seaport is to be fossil-free and climate positive by 2030 and to lead the way as a test bed for the transition. An early study found that building energy use and transportation were responsible for an equal amount of greenhouse gas emissions. The most important measures are to build energy-efficient buildings and implement a traffic hierarchy. Replacing fossil fuels in both the energy and transportation systems is also important, but more difficult to implement as it lies outside the City's jurisdiction.

Energy-efficient buildings and local production of renewable energy

The starting point for energy-efficient buildings is the principles of the , which primarily aim to reduce energy demand and secondly to use renewable energy sources. To ensure technology neutrality, functional requirements are set where the specific energy consumption would be halved to 55 KWh/m2  Atemp compared to the current, Swedish building code regulations , where electric heating is weighted with a factor of 2. This requires a well-insulated climate shell and energy-efficient installations, which have contributed to the development of technology, insulation, and control and regulation systems, as well as increased use of waste heat recovery systems. Over 70 per cent of the buildings in the Stockholm Royal Seaport are connected to the district heating system.

To succeed in a sustainable energy transition, more renewable energy needs to be produced locally. Since wind power is not suitable in densely populated areas due to safety reasons, requirements are set for solar energy to be generated on buildings and facilities. To avoid forcing property developers to produce more electricity than their own needs, the requirement was set at a minimum of 2 kWh/m2  Atemp. Another important aspect is that Swedish green electricity has a lower emissions factor than locally produced solar electricity, which also played a role in the requirement setting. So far, a majority of developers have chosen to primarily install photovoltaics on the roofs.

Management throughout the development process gives results

The requirements that are set are combined with in-depth monitoring and external review of submitted verifications and calculations during design, construction and management phases. Many important lessons have been learned. Measured energy values showed that the projected values were exceeded, which meant that the requirements were not fully met. Over the years, dialogue has been held with the developers regarding troubleshooting and corrective actions; the largest deviations were high consumption of thermal energy and measurement errors.

The analysis shows that there are shortcomings in the transfer from design to construction and from construction to management. The allocation of responsibilities between the developer, the design team, energy coordinator and building contractor is of great importance. The dialogue has led to the identification of the cause and effect of deviations. Energy consumption has then decreased by about 10 per cent compared to measured energy consumption year one. Measures include adjusting air flows, control regulation, adjusting indoor temperature and introducing measurement routines.

A significant knowledge platform has been established through the active and transparent collaboration of all parties involved. Sharing of lessons learned from the development phase Norra 2 has spread to subsequent phases and projects within the City of Stockholm. An exchange of experiences is ongoing. An important result is that the follow-up work has contributed to the development of knowledge in the construction industry as a whole.

Plus Energy District - from buildings to district level

Over the last decade, the focus has been on creating the conditions for energy-efficient buildings. To test the concept of plus-energy buildings, a site allocation competition was held, resulting in Stockholmshems two plus-energy buildings. To further optimise energy use and produce energy locally contributing to plus-energy districts, a systematic approach on a district level need to be applied. Energy-efficient buildings need to be combined with, among other things, recovery of waste energy and increased local production of renewable energy where sharing and storage of energy play an important role. Stockholm Royal Seaport is collaborating with Brussels and Vienna to develop strategies for creating plus-energy districts and to define and clarify what it means and entails.

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Two people placing solar panels on the roof of the Mass Consolidation Centre.
More than 1,500m² of solar panels on the roof of the MCC produce approximately 270MWh per year

Improved charging infrastructure

The shift to fossil-fuel-free transportation requires vehicles to run on electricity or renewable fuels. The need for electric charging stations has increased in recent years. To facilitate this, charging infrastructure is being built in parking garages are supplied with charging infrastructure. The requirement has also been adjusted, and in future land allocations, at least 50 per cent of the parking spaces must be equipped for electric charging. Tests with battery storage for rapid charging of the electric truck are underway at the .

Low climate impact

According to research conducted by the IVL Swedish Environmental Research Institute, the construction process contributes to a larger proportion of climate emissions compared to the operation of a building over 50 years. With the energy requirements Stockholm Royal Seaport and Stockholm's district heating mix, the conventional construction process accounts for almost 70 per cent of the total climate footprint.

In the first development phase, requirements were imposed for making a climate calculation. As there was a lack of a common method, it was difficult to compare results between buildings. IVL, in collaboration with the City of Stockholm and other municipalities, developed the Construction Sector’s Environmental Calculation Tool as an industry-wide approach. Developers are now required to make climate calculations from the early stages and to develop an action plan to reduce emissions. In coming land allocations, limits for climate impact will be imposed.

Aerial view of green rooftops and solar panels in phase Norra 2.
To contribute to a fossil-free energy system, solar electricity or solar heat is produced in all new buildings
Building with LED street light.
LEDs are used to illuminate public spaces and security lighting has been installed in certain areas
View of the plus-energy buildings in Brofästet seen from Husarviken. High grass and three boats in the foreground.
Plus-energy building in Brofästet, seen from Husarviken

The City has begun imposing climate requirements for concrete and steel in all construction contracts for public open space. To drive progress forward, a pilot project is being carried out in which 20 per cent and 50 per cent of the cement in concrete is replaced with blast furnace slag in a temporary pile deck and a temporary base plate. The pilot will be evaluated over time.

An important outcome is that the work with climate calculations on public space within Stockholm Royal Seaport has spread to other projects within the city. An organised exchange of experiences and tools has begun.

Visualisation of Kolkajen. Residences along the waterline with the Gasworks area in the background.
A visualisation of Kolkajen and the marine park.SWECO
Visualisation of Kolkajen. Adults and children walk on a dock along the water, bathing and playing. Residences in the background.
Docks for swimming in KolkajenSWECO

To better understand the climate impact from different parts of a detailed development plan, an overall climate analysis was carried out for Kolkajen. The analysis will serve as a basis for optimising the construction process from a climate perspective. The major parts of public space that contribute to a significant climate impact are the remediation and stabilisation of existing site and the creation of new land by moving the quay line outwards.

The analysis shows that for this detailed development plan, the construction of public space accounts for two thirds of the climate impact. It also shows that with the sustainability requirements, the impact can be reduced by approximately 20 per cent. The analysis has provided further basis for continuing the work of finding methods to reduce the amount of concrete in these parts. Of the developers assigned, several have ambitions to build in wood and the others with conventional concrete structures. The climate calculation of the buildings has used outlines from 2022. With the City's sustainability requirements, the climate impact can be reduced by 30 per cent. When the developers start their projects, the goal is to further reduce the climate impact.

An initial climate calculation was carried out for Saltkajen. The result shows that pile walls contributed to 45 per cent of the CO2-emissions and concrete usage 19 per cent. In collaboration with the City's experts, it was decided to fill the pile walls with crushed material instead of concrete, thus reducing the carbon footprint. Other measures are to use slag-mixed concrete, and various concrete recipes will be tested to determine what can be used for the construction. The contractor is also reviewing the possibility of minimising the overall use of materials through smarter structural solutions.

Biochar as carbon sink

Biochar is used in most of the plantings along streets in the area, contributing to a carbon sink. The plant substrate consists of biochar-mixed gravel. Biochar improves soil quality and binds CO2. By using biochar in Stockholm Royal Seaport, the project contributes to a carbon sink. To date, the equivalent of 5,400 tonnes of CO2 has been bound in the organic material.

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Key events and figures in 2022

  • Experience feedback on measured energy performance took place with developers in Brofästet, Gasverket, and Jackproppen. Adjustments and troubleshooting are in progress.
  • 600 MWh of solar energy was produced on the roofs of completed phases. 295 MWh of solar energy was produced at the Mass Consolidation Centre and the Construction Consolidation Centre.
  • All carpool spaces have electric charging and 14% of the parking spaces on private properties have electric charging.
  • Electricity used in the City's and developers' operations is 100% renewable. 44% of fuel used for the City's vehicles and machinery was renewable, primarily HVO100. This is an increase of 9 percentage points from the previous year. Two major contractors have chosen to set even higher requirements and plan to use 100% HVO100.
  • 48% of the total energy consumed (fuel and electricity) in the City's operations was from renewable sources.
  • An estimated 175,000 kWh of energy was used for lighting.

Achievements for 3. Energy and climate

3.3 Fossil-fuel free energy and transport system

On average, Norra 2 is 67 kWh/m² (66 kWh/m2 according to Swedish building code regulations BBR19 and 20) On average, Brofästet is 65 kWh/m² (54,5 according to BBR23 and 24)

In 2019 residents survey, 33% of households have agreements on eco-labeled energy.

In total, approximately 895 MWh of solar energy was generated locally 2022.

8% of car parking spaces in the streets have electrical charging (carpooling) and a fast charging station. Additionally, 14% of car parking spaces on development sites are equipped with electrical charging.

There are currently two filling stations for 100 in Stockholm Royal Seaport.

44% of the fuel used for machinery and vehicles in development sites during 2022 has been renewable. (35% in 2021).

3.4 Low climate impact

Average climate impact (public open spaces): Norra 1: 460 kg CO2e /m2, Västra: 3,130 kg CO2e /m2, Norra 2: 270 kg. CO2e /m2.

Climate impact from energy use in Norra 2: Total amount is 1,640 tonnes CO2e equivalent to approx. 248 kg CO2e/person.

Updated: 23/02/2024