*4.2. Energy Savings and Reduced Environmental Impact of Electrical Power Systems for Transportation*

One of the findings of this study is that GHGs for solar-powered BEVs are nominal. Battery-electric power systems powered by PVS produce an environmental impact that is almost negligible. When electrical grid power is used for charging EVs under the conditions of Scenario 2, the simulation depicts reductions in CO2, NOx + NMOG, and CO. For CO2, that lifecycle reduction is from about 60,000 kg (ICEV) to 25,000 g (PHEV). For NOx + NMOG, lifecycle reductions are estimated to be from 17.5 kg (ICEV) to 10 kg (PHEV). CO estimates were 450 kg for ICEV versus 225 kg for PHEV. Under both scenarios, EV adoption resulted in a reduced environmental impact.

The verdict on true GHGs, however, may be mixed. A recent study has proposed a more robust method for capturing grid energy CO2 emissions in the electricity production phase [62]. The results suggest that under some conditions, ICEVs might be preferred. This result is surprising and underscores the value in PVS offsets for electrical charging requirements [23].

The total kWh for the BEV operating at 0.34 kWh/mile for 1100 miles × 12 months × 8 years is 35,904 lifecycle kWh, about 4408 kWh monthly. (The 0.34 kWh/mile is a variable parameter in the simulation.) With approximately 1 million BEVs on the road today [63], the additional monthly kWh demand is 4408 GW at the rate of consumption. EV loads are now placing pressure on power grids [64]. Using PVS for recharging these vehicles could offset that increased demand. Given that EVs may increase global consumption of electricity between 11–20% by the year 2040 [65], this type of solution along with smart grid and others may prove vital.

## *4.3. Implications*

This simulation has policy implications for both the government and the manufacturers. First, the use of tax credits visibly accelerates break-even analysis in the online simulation. Tax credits for hybrid and BEV should be considered an investment in the environment [58]. Second, the expansion of EVs is likely to result in an 11–20% increase in grid demand by 2040 [65]. The solutions to this problem might include smart grid development acceleration or incentives for renewable recharging.
