TABLE F.1 Metric Prefixes

Unit Multiple

Metric Prefix

Symbol

Value

103

kilo

k

Thousand

106

mega

M

Million

109

giga

G

Billion

1012

tera

T

Trillion

1015

peta

P

Quadrillion

  • A typical power plant is defined here as one with a generating capacity of 500 megawatts (MW) that operates for slightly less than 5000 hours per year1 and is thus selling 2.5 billion kWh per year (or 2.5 terawatt-hours [TWh]; tera = 1012 = trillion; see Table F.1). Although a typical 20-year-old power plant has a generating capacity of about 1000 MW, or 1 gigawatt (GW; giga = 109 = billion), the typical power plant as defined here is smaller because newly constructed power plants tend to have a capacity of about 500 MW.

The typical uses of energy and electricity given in the definitions above are shown in Column A of Tables F.2F.4. Table F.1, “Metric Prefixes,” is the basis of all notations used in Tables F.2F.4.

WHICH TABLE TO USE

The conversion by energy (Table F.2), electricity (Table F.3), and C or CO2 (Table F.4) differs by up to 50 percent. The choice of which table to use depends on one’s “model.” Those most interested in saving money, primary energy, and air pollution will prefer Table F.2, but those focusing on electricity trade-offs would use Table F.3 (which does not include cars), and those addressing CO2 trade-offs would choose Table F.4.

1

A more accurate number is 4850 hours per year (3300 billion kWh/680 GW from Table 7.1 in Monthly Energy Review, February 2001, and Table 35 in 1999 Electric Power Annual, Volume 2, Energy Information Administration, Department of Energy, Washington, D.C., October 2000, respectively).



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