Towards 100% fossil-free Helsinki

This scenario aims at giving an idea of a clean energy mix that diverse players including new producers, flexibility providers, prosumers etc. could provide in cooperation with Helen Ltd to phase out fossil fuels from the capital city of Finland.

The following estimations are calculated based on the 100% fossil fuel-free scenario for Finland, reflected to the 630 000 citizens of Helsinki representing 12% of the total population of 5,5 million. Therefore, the estimations do not necessarily reflect the real energy need of the City of Helsinki.

Helen Ltd., a utility company fully owned by the City of Helsinki, is a producer of district heating, power and district cooling. Helen supplies heat to 90% of the heated building stock in Helsinki. Therefore Helen Ltd’s production portfolio and installed capacities in 2017 are used in the scenario as “baseline reference” in order to point out the necessary changes in the energy sources and technologies when heading towards a 100% fossil-free Helsinki.

Given the considerations presented above, if the City of Helsinki would make a transition to a 100% fossil fuel-free scenario the needed energy sources for heating would be as presented in the following figures:

The district heat production in Helsinki hour-by-hour based on 100% fossil-free energy scenario during a year. In reality the running patterns are significantly smoother than in this figure drawn with EnergyPLAN simulation tool. Even though the curve shape does not reflect the real heat demand of Helsinki, we have run simulations with different heat consumption profiles and the curve shape is not that important for the final results. The exact dimensioning and technical solutions need to be tailored case by case depending on the real heat demand.
Installed heat production capacity by Helen Oy in 2017 and capacities and energy sources in 100% fossil-free scenario for the City of Helsinki

If Helsinki would become self-sufficient for the part of the electricity required to run the heat pumps, 700 megawatts (MW) of wind power would be needed. Furthermore, 400 megawatts of solar power could be added. However, it is not as important as wind power. The estimated wind power capacity is calculated taking into account that wind power production is used for many different purposes, of which 700 MW is needed as extra capacity to take care of the heating needed in this scenario. The possibility to use electricity for heating especially when there is a surplus of electricity, will reduce the required capacity. In other words, storages in combination with wind power, heat pumps and bio-CHP, will increase the system efficiency.

Heat pumps require excess and ambient heat sources. In Helsinki these sources can consist of urban excess heat, sea water, air and boreholes. The exact sources and their shares need to be studied more in detail.

In the 100% fossil fuel-free district heating scenario for Helsinki, we assume less bio-CHP than the national average would suggest. The transportation of domestic biomass to Helsinki can be a challenge and the required storage space of the biomass may be a problem, because of high land prices. Moreover, the current CHP plants in Helsinki are technically difficult to convert to use biomass. For these reasons, we assume, that bio-CHP will be used more in other district heating networks of Finland for the national power balancing needs, while heat pumps are more numerous in Helsinki.

FREQUENTLY ASKED QUESTION:

How many wind turbines and heat pumps would be needed in Helsinki to phase out coal?

  • Helen Ltd used in 2016 6,9 TWh of coal, 4,6 TWh of natural gas and 0,2 TWh of oil for the production of district heating and power. Most of these fossil fuels could be replaced with 1100 megawatts of heat pumps presented in the scenario. That would require additional 950 MW of heat pump capacity on top of the upgraded Katri Vala’s 123 MW and Esplanade park’s 22 MW heat pump stations. So the required increase in heat pump capacity (950 MW) could be covered with approximately ten new large heat pump stations or 19 000 units of 50 kW heat pumps in buildings.
  • 1100 megawatts of heat pump capacity require approximately 400 megawatts of electric power. Due to the variability of wind power, in practise this requires 700 MW of wind power capacity, which is equal to 170 units of four megawatt wind turbines.

The 100% fossil-free scenario shows, that different production technologies – together with flexibility solutions – interact in such critical ways, that they must be modelled together in order to get a correct understanding of the technologies needed.

The wind farms do not need to be located next to the district heating networks, as electricity grids can transmit wind power from distant locations. The wind turbines providing electricity for the heat pumps in Helsinki can be located for example in the Pohjanmaa region.

However, wind farms as well as other renewable energy power plants impacting local communities, need to be developed according to the principles of procedural and distributive justice to minimize public opposition. Procedural justice in renewable energy development means that citizens and local communities should be actively involved in the decision-making processes regarding wind farms planning and situating. Distributive justice instead refers to the issue of who really benefits from wind power projects. Wind farms can offer a great opportunity for local economic development in rural areas. Therefore, community ownership or joint ownership with project developers can be encouraged to create a win-win situation in which both citizens living in rural and urban areas can benefit from wind energy. The dramatic reduction in the costs of wind power generation as demonstrated by the recent PPA (Power Purchase Agreement) deal signed by Google to buy renewable energy from wind farms in Finland, creates new opportunities for local communities to co-invest in wind energy.

More information:

Samuli Rinne, Karoliina Auvinen, Francesco Reda, Salvatore Ruggiero and Armi Temmes. 2018. Discussion paper: Clean district heating – how can it work? (pdf). Publication of the Smart Energy Transition project funded by the Academy of Finland’s Strategic Research Council.