■ Under construction ■ Planned ■ Additions needed by 2030 Source: IEA analysis. Data for plants under construction and planning are from plants (2003).

FIGURE 1.4 Electrical capacity requirements by region. (From IEA, World Energy Outlook, IEA, Paris, 2004. With permission.)

which project an average annual growth of about 2%—2.5% up to 2030. It is clear that of all countries, China will add the largest capacity with its projected electrical needs accounting for about 30% of the world energy forecast. China and India combined will add about 40% of all the new capacity of the rest of the world. Therefore, what happens in these two countries will have important consequences on the worldwide energy and environmental situation. If coal provides as much as 70% of China's electricity in 2030, as forecasted by IEA (IEA 2004), it will certainly increase worldwide CO2 emissions, and further increase global warming.

1.3 Transportation

Transportation is another sector that has increased its relative share of primary energy. This sector has serious concerns as it is a significant source of CO2 emissions and other airborne pollutants, and it is almost totally based on oil as its energy source (Figure 1.5; Kreith, West, and Isler 2002). In 2002, the transportation sector accounted for 21% of all CO2 emissions worldwide. An important aspect of future changes in transportation depends on what happens to the available oil resources, production and prices. At present, 95% of all energy for transportation comes from oil.

As explained later in this chapter, irrespective of the actual amount of oil remaining in the ground, oil production will peak soon. Therefore, the need for careful planning for an orderly transition away from oil as the primary transportation fuel is urgent. An obvious replacement for oil would be biofuels such as ethanol, methanol, biodiesel, and biogases. Some believe that hydrogen is another alternative, because if it could be produced economically from RE sources or nuclear energy, it could provide a clean transportation alternative for the future. Some have claimed hydrogen to be a "wonder fuel" and have proposed a "hydrogen-based economy" to replace the present carbon-based economy (Veziroglu and Barbir 1992). However, others (Shinnar 2003; Kreith and West 2004; Mazza and Hammerschlag 2005) dispute this claim based on the lack of infrastructure, problems with storage and safety, and the lower efficiency of hydrogen vehicles as compared to plug-in hybrid or fully electric vehicles (West and Kreith 2006). Already hybrid-electric automobiles are becoming popular around the world as petroleum becomes more expensive.

The environmental benefits of renewable biofuels could be increased by using plug-in hybrid electric vehicles (PHEVs). These cars and trucks combine internal combustion engines with electric motors to

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