Petroleum will continue to be an indispensable transportation fuel during the time periods considered in this report, but maintaining current rates of domestic petroleum production will be challenging. There are limited options for replacing petroleum or reducing petroleum use before 2020, but there are more substantial longer-term options that could begin to make contributions in the 2030–2035 timeframe. The options include increasing vehicle efficiency, replacing imported petroleum with other liquid fuels produced from biomass and coal that have CO₂ emissions similar to or less than that of petroleum-based fuels, and electrifying the light-duty vehicle fleet.

The United States consumed about 21 million barrels of liquid fuels¹⁶ per day in 2007. Domestic consumption of liquid fuels is projected to increase to about 22 million barrels per day in 2020 and about 23 million in 2030 (EIA, 2008). In 2007, about 14 million barrels of liquid fuels per day were used in the transportation sector, of which about 9 million barrels were consumed by LDVs.

The best near-term option for reducing dependence on imported petroleum is through greater vehicle efficiency. The EISA requires a 40 percent increase in fuel economy for new LDVs by 2020. This could eventually result in a savings of about 1.4 billion barrels of gasoline per year (60 billion gallons of gasoline per year or about 164 million gallons of gasoline per day) when these fuel economy standards are fully realized in the on-the-road fleet. As noted previously, the Obama administration recently announced a new policy that requires an average fuel economy standard of 35.5 miles per gallon for new LDVs in 2016. As explained in Chapter 4, further efficiency gains are projected after 2020.

Reducing dependence on imported petroleum by substituting domestically produced liquid fuels would seem to be a good strategy, but the near-term options are limited. Just maintaining current rates of domestic petroleum production (about 5.1 million barrels per day in 2007) over the next two to three decades will be challenging. Petroleum production in current fields is declining, and it will be difficult to increase domestic production even with favorable developments in technology, prices, and access to new resources. Nevertheless, continued devel-