Getting to Zero: A Pathway to a Carbon Neutral Seattle

This report, prepared by the Stockholm Environment Institute and partners for the City of Seattle, develops a 'Carbon Neutral' scenario to demonstrate a pathway for the city to achieve net zero greenhouse gas (GHG) emissions by 2050. The analysis focuses on 'core' emissions—buildings, transportation, and waste—where the city has the most direct policy influence. The scenario suggests that aggressive implementation of efficiency and fuel-switching strategies could reduce per capita GHG emissions by 90% by 2050 relative to 2008 levels.

• The Carbon Neutral scenario projects that implementing a comprehensive suite of emission-reducing strategies could lower Seattle's per capita GHG emissions by 30% by 2020, 60% by 2030, and 90% by 2050, compared to 2008 levels.
• Transportation is the largest source of core emissions; the scenario aims for a 90% reduction in road transportation emissions by 2050 through a combination of reducing vehicle miles travelled (VMT), increasing fuel economy, and transitioning to electric vehicles (EVs) and biofuels.
• To reduce passenger vehicle travel, the scenario proposes increasing the transit mode share from 8% to 25% by 2050, implementing VMT and congestion pricing, and expanding bicycle and pedestrian infrastructure to reach a 30% bike trip share by 2050.
• The scenario assumes a transition to zero-carbon vehicles, projecting that the share of electric or hydrogen fuel cell light-duty vehicles could reach 80% by 2050, with medium- and heavy-duty trucks reaching 53% and 27% penetration respectively.
• Building emissions are targeted for a reduction of nearly 80% below 2008 levels by 2050. This is to be achieved through 'aggressive' and 'deep' energy efficiency designs for new buildings and retrofits for existing stock, alongside a shift to electric heat pumps and biomass-powered district energy.
• Seattle's electricity supply is currently net zero carbon due to hydroelectric resources. The scenario assumes this status can be maintained through 2050, provided that efficiency gains in buildings offset the increased demand from EV charging and heat pumps.
• From a 'waste commitment' perspective, net emissions from waste management are near zero because the carbon stored in landfills roughly offsets the emissions from methane and transportation. Increasing diversion to 70% by 2025 provides significant indirect life-cycle benefits but negligible direct GHG changes.
• A consumption-based perspective reveals that Seattle's emissions are significantly higher than core measurements, estimated at 25 tonnes CO2e per capita in 2008, with approximately 40% associated with the production of food and goods.
• Because the Carbon Neutral scenario only reduces emissions by approximately 90%, reaching absolute net zero by 2050 may require offsets, such as biological carbon sequestration in forests and soils, or selling excess renewable energy.

APA

Lazarus, M., Erickson, P., Chandler, C., Daudon, M., Donegan, S., Gallivan, F., & Ang-Olson, J. (2011). Getting to Zero: A Pathway to a Carbon Neutral Seattle. Stockholm Environment Institute. https://cdn.leap.sei.org/documents/SEISeattleZeroCarbon2011.pdf

Chicago

Lazarus, Michael, Pete Erickson, Chelsea Chandler, Marc Daudon, Shannon Donegan, Frank Gallivan, and Jeffrey Ang-Olson. Getting to Zero: A Pathway to a Carbon Neutral Seattle. Stockholm Environment Institute, 2011. https://cdn.leap.sei.org/documents/SEISeattleZeroCarbon2011.pdf.

Wikipedia

{{cite report |last1=Lazarus |first1=Michael |last2=Erickson |first2=Pete |last3=Chandler |first3=Chelsea |last4=Daudon |first4=Marc |last5=Donegan |first5=Shannon |last6=Gallivan |first6=Frank |last7=Ang-Olson |first7=Jeffrey |title=Getting to Zero: A Pathway to a Carbon Neutral Seattle |publisher=Stockholm Environment Institute |date=May 2011 |url=https://cdn.leap.sei.org/documents/SEISeattleZeroCarbon2011.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{lazarus2011getting, author = {Lazarus, Michael and Erickson, Pete and Chandler, Chelsea and Daudon, Marc and Donegan, Shannon and Gallivan, Frank and Ang-Olson, Jeffrey}, title = {{Getting to Zero: A Pathway to a Carbon Neutral Seattle}}, institution = {Stockholm Environment Institute}, year = {2011}, month = may, url = {https://cdn.leap.sei.org/documents/SEISeattleZeroCarbon2011.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }