scenario we assumed that both of California nuclear units are not in the resource mix. The resulting incremental emission factors, shown in Table 4-23, are slightly higher for most areas within California since existing gas-fired power plants are providing more incremental energy5.
The Scenario 2 results show that approximately 95 percent of the incremental energy from regions outside of California are gas-fired and about 5 percent is coal-fired. This lesser amount of imported incremental coal-fired generation is the reason for the lower incremental emission factors outside of California.
Differences between Resource Plans 1 and 2 results are most apparent within California air basins where new gas-fired power plants are located. For example, under Scenario 2 assumptions, there is more incremental generation from the Sacramento Valley and San Francisco Bay Area air basins because more new gas-fired resources are added to these locations. However, the out-of-state differences between Research Plans 1 and 2 tend to be more a function of which units the Multisym™ predicts to be forced out, rather than a result of new generation.
Moreover, these incremental results are similar to those results generated in the Energy Commission’s 1995 EV Report and reported in the Acurex fuel cycle study. The principal difference is in the mix of incremental energy imported from areas outside of California. The majority of imported energy to meet a slight increase in off-peak demand tended to be gas-fired. Previously, a constant mix of gas, hydro and coal-fired generation from imported energy was assumed.
The fraction of imported power has a significant effect on marginal emissions in the SoCAB. In Resource Plans 1 and 2 about 21 percent of the power is generated in the SoCAB for purposes of evaluating marginal emissions from EVs, the NMOG emission factor is 5.4 tons/800 GWh or 0.006 g/kWh.
5 Existing generation outside of the South Coast Air Basin is not assumed to be retrofit with additional emission control equipment