Modelling tasks

For Tallinn the following domains were modelled and conclusions introduced:

• Mitigation
  • Transport
  • Energy demand and energy supply
• Adaptation
  • Micro climate and heat islands
• Impact on Health
• Behaviour - Climate Coping Types

Observations and conclusions

Transport: Policy Effectiveness and Synergies

• Policy Effectiveness Varies Greatly:
  • Measures like road and area pricing have a far stronger impact on reducing car usage than urban design or planning alone.
  • Public transport usage increases primarily due to car pricing measures, rather than improvements in transit networks.
• Synergy Matters:
  • Combined "all measures" scenarios significantly reduce car use, demonstrating the compounding effects of policies.
  • Direct CO₂ emissions are mainly reduced by fleet transformation (e.g., shifting to electric vehicles).
• Not All Green Measures Reduce Car Use:
  • Fleet transformation might trigger a rebound effect, increasing car usage despite environmental improvements due to higher energy demand.

Energy Demand: Fossil Dominance and Decarbonization Pathways

• The energy balance of Tallinn (2019) shows a high reliance on fossil fuels, with:
  • 21% from motor fuel and 13% from fossil energy carriers.
  • The building sector is the largest consumer (household: 36%, service: 26%), followed by manufacturing (16%) and passenger transport (17%).
• Climate neutrality in Tallinn’s energy system is achievable by 2050, except in the transport sector, reducing emissions from 2.06 t CO₂/capita (2019) to 0.09 t CO₂/capita (2050).
• Impact of Heat Waves on Energy Demand:
  • Cooling demand increases by 310% in the building sector.
  • Space heating demand decreases by 1.25%.
  • Total energy demand across all sectors drops by 0.29%.

Energy Supply: Electrification and System Resilience

• General Conclusions:
  • Limited local renewable energy (RES) potential, meaning the national grid will remain dominant.
  • High electrification across all sectors, including district heating (DH).
  • Electricity demand rises due to heat pumps (HP) and electric boilers (E-boilers) in DH and H₂, exceeding core projections by 5–7%.
• Impact of Heat Waves on Energy Supply:
  • Cooling demand during heat waves does not significantly stress the local electricity supply compared to normal years (NY).
  • Slightly higher electricity and DH capacity is required during heat waves.
  • A hot summer does not necessarily predict a warmer winter, highlighting seasonal variability.

Health Impact and Microclimate: Benefits of Adaptation Measures

• Model Scenarios (2030–2040):
  • 2030: Early benefits from energy-efficient buildings (~3,800 new trees) reduce hospital costs, but critical hotspots remain.
  • 2040: Stronger impacts from 20% building retrofitting, 30% desealing & greening, and ~2,500 extra trees lead to a significant decrease in high-cost hospitalization areas.
  • Maps show a shift from high to low hospitalization cost classes, proving the effectiveness of integrated adaptation measures.
• Health and Epidemiological Insights:
  • Lack of disaggregated mortality data limits full model exploitation (e.g., lagged temperature effects).
  • Historical trends show stronger winter impacts than summer, with overall temperature-associated mortality decreasing under climate change.
  • Heat stress exposure is expected to rise due to longer warm seasons, requiring adaptation measures (e.g., building materials, urban greening) and close monitoring of heat-related illnesses.

Behavior: Policy Timing, Rebound Effects, and Targeted Communication

• Climate Coping Typologies provide insights into different reactions to climate policies, enabling:
  • Refinement of pathway modeling by assessing measure effectiveness and side effects.
  • Planning targeted information campaigns to guide public behavior.
• Policy Timing Matters:
  • Delaying measures in hopes of greater future acceptance does not work—timely action is crucial.
  • Rebound and backfire responses (e.g., increased energy use despite efficiency gains) must be mitigated through legislation and communication.
• Targeted interventions help align public behavior with desired climate outcomes.

The modeling results are considered highly relevant and valuable for updating Tallinn’s Climate Plan 2030 and achieving the 2050 climate neutrality goal. Participants particularly appreciated the systematic integration of mitigation and adaptation, the clarity of the GIS maps, and the "Pathway" concept as effective tools for guiding long-term planning.

Key challenges and requests were identified to enhance the practical use of these results for policy-making and political persuasion:

• Scenario Alignment:
  There is a discrepancy between the KNOWING model (based on the extreme SSP585 scenario) and Estonia’s national projections (based on the moderate SSP2-4.5 scenario). Stakeholders requested recalibration to align with the local "Global Warming Level" approach for consistency with national strategies.
• Data Transparency:
  A detailed, report-style explanation of input data is needed, distinguishing between local, WHO, OECD, and Eurostat sources. Officials also require a clear overview of methodology and data limitations to confidently defend the results to politicians.
• Guidance for Policymakers:
  The city needs clear instructions on how to interpret and communicate these outputs to decision-makers. A section with prioritized recommendations and cost-effectiveness assessments would be highly beneficial.

Sector-specific feedback highlighted areas requiring adjustments:

• Energy (Correction Needed):
  The model significantly underestimates District Heating capacity, projecting ~47 MW of heat pump capacity by 2050, while the local provider (Utilitas) is launching a 110 MW station next year and targets 200 MW by 2050.
• Transport (Detail Needed):
  Since transport is the only sector with rising emissions, the city needs granular data on the impact of individual measures. Specifically, a breakdown of CO₂ reduction and modal shift for each intervention is requested.

Next steps include organizing a dedicated workshop to discuss the "Mitigation Pathway" in greater detail.

Summary of Tallinn’s exploitation plans following the Climate Mitigation Pathway development

In the aftermath of the Pathway seminar, opportunities for local implementation of the pathway and exploitation were established in the Tallinn local hub.

Key Takeaways

• Heat Hotspot Package: Short-term, actionable tool for prioritizing public health and service reliability in heat-vulnerable areas.
• Climate Proofing Map: Medium-term integration into planning standards to embed climate risks into routine decisions.
• Policy Briefs: Immediate tool to reframe climate action as politically robust, tied to core municipal responsibilities (health, affordability, resilience).

All three exploitation projects aim to bridge the gap between modeling results and practical implementation, ensuring scalability for cities with similar challenges.