Scenario Analysis

Scenario Planning

The planning team commissioned a scenario analysis tool to model how identified climate actions could reduce greenhouse gas emissions. The ultimate goal of this exercise was to assess the contribution of the draft plan actions toward achieving the regional emission reduction targets. The tool modeled anticipated changes across twenty-three metrics and provided instant visual feedback of associated greenhouse gas reductions.

The Role of Federal and State Policy

Outcomes from the scenario planning process suggest that anticipated state and federal policies will reduce emissions considerably compared to a business-as-usual scenario (see grey “wedges” in the figure below). Influential policies include the state building code, WA State Clean Energy Transformation Action (CETA), and anticipated increases to vehicle fuel economy standards, with CETA being the most impactful in reducing anticipated greenhouse gas emissions. The business-as-usual (BAU) scenario provides an estimate of potential future emissions, assuming that the Thurston region takes no further action. It considers the influence of external factors on emissions, such as population growth, changes in the regional electricity fuel mix, and energy demand. 

The Role of Local Action

Meeting the TCMP emission reduction goals will require additional local action beyond what will be achieved through federal and state policy. The anticipated impact of local action is shown in colored “wedges” in the figure below. The largest contributor of local reductions is anticipated to be improvements in the transportation sector.

The cross-hatched area represents greenhouse gas reductions that could be achieved through carbon sequestration (absorbing carbon pollution into vegetation and soils). Together with local action and broader policies, we anticipate that the Thurston region can achieve the targets of 45% and 85% reductions in greenhouse gas emissions by 2030 and 2050, respectively.

CETA = WA State Clean Energy Transformation Act | ZEV = WA State Zero Emission Vehicle mandate |

CAFE = federal vehicle fuel economy standards

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