2014/07/16 Council Agenda Packet

lack of available research on the benefits of existing strategies to reduce greenhouse gas emissions, we remain conservative on the range of emissions reductions assumed. SECTION 2: METHODOLOGY This section describes how the assumptions for the two technology scenarios — likely and aggressive — were applied to the output of the Transportation 2040 alternatives analysis. EPA's draft MOVES Demo model was utilized to estimate greenhouse gas emissions for Transportation 2040. However, this version of the draft model did not have the capability to adjust for advanced vehicles or fuel scenarios, so our approach involved post - processing each assumption to the emissions results produced by the integration of PSRC's modeling framework. Each assumption under both scenarios was carefully applied to only the appropriate output, and the adjustments described above were made so as to avoid double counting of benefits. 2A. Percent of Electric Vehicles in the Central Puget Sound Vehicle Fleet • Likely Scenario: 20% • Aggressive Scenario: 45% The assumptions for the percentage of electric, plug-in hybrid electric or other zero to low emission vehicles in the fleet were applied only to the emissions output from passenger cars and light -duty trucks3. For the purposes of this analysis as applied to Transportation 2040, these vehicles were assumed to have zero tailpipe emissions (see below for a discussion of other emissions implications from these vehicles). ■ Likely Scenario (20%): a 20% reduction was applied to the greenhouse gas emissions results from Transportation 2040 for passenger cars and light trucks. Aggressive Scenario (45%): a 45% reduction was applied to the greenhouse gas emissions results from Transportation 2040 for passenger cars and light trucks. Significant discussion was held regarding whether it was appropriate to describe these vehicles as having "zero emissions." There was some concern expressed that this description does not adequately convey that there are, in fact, "upstream" emissions that may be created from the generation of the electricity used for these vehicles. At this point in time, all emissions results analyzed at PSRC — whether for Transportation 2040, the Regional Transportation Improvement Program or other analyses — only report on on -road vehicle tailpipe emissions. It is this category for which PSRC has state and federal requirements through transportation conformity. The analysis of "upstream" or "lifecycle" emissions is an area for which there is no standard methodology or guidance currently available. We do not conduct such an analysis for any other component of our plan — for example, upstream emissions impacts from gasoline production, materials production for concrete/cement/steel for building infrastructure, emissions impacts from the construction and operation of buildings, vehicle production, etc. We do, however, want to stress that the results as described in Transportation 2040's Four -Part Greenhouse Gas Strategy reflect only on -road vehicle emissions, and we recognize that the source of fuel used for any future vehicle fleet may have additional greenhouse gas emissions not reflected in our reporting. There has been some movement in Washington State and the Puget Sound region, however, to ensure that the electricity for vehicles will come from alternative sources and utilize the grid off-peak. These strategies, if adopted, will mitigate any "upstream" emissions from these vehicles. 2B. Improvements to Vehicle Fuel Economy • Likely Scenario: 40 mpg • Aggressive Scenario: 50 mpg In order to avoid double counting of benefits, the assumptions for improved vehicle fuel economy were applied to the remainder of the passenger vehicle fleet, after the reductions under 2A were applied. For the purposes of 3 PSRC's modeling output can be segregated into passenger vehicles, light trucks, medium trucks and heavy trucks. L-7 Appendix L: Climate Change Background