Energy Solutions to Air Pollution and Global Warming - Air Pollution and Global Warming: History, Science, and Solutions - page 326

Table 13.4. Number of wind, water, and sunlight (WWS) power plants or devices needed to provide the world
and U.S. total end-use power demand in 2030 (11.5 and 1.8 TW, respectively, from Table 13.2)

Rated
power of
one plant/
device
(MW)

Percent of
2030 power
demand
met by
plant/device

Footprint
area
(percent
of global
land area)

Spacing
area
(percent of
global
land area)

Number of
plants/devices
needed
worldwide

Number of
plants/devices
needed in
United States

Energy
technology

Wind turbine 5 50 3.8 million 0.000033 1.17 590,000

Wave device 0.75 1 720,000 0.00026 0.013 110,000

Geothermal plant 100 4 5,350 0.0013 0 830

Hydroelectric plant 1,300 4 900 a 0.407 a 0 140 a

Tidal turbine 1 1 490,000 0.000098 0.0013 7,600

Roof PV system 0.003 6 1.7 billion 0.042 b 0 265 million

Solar PV plant 300 14 40,000 0.097 0 6,200

CSP plant 300 20 49,000 0.192 0 7,600

TOTAL 100 0.74 1.18

TOTAL NEW LAND 0.41 c 0.59 c

This table assumes the given fractionation of demand among plants or devices while accounting for transmission, distribution, and array
losses. Also shown are the footprint and spacing areas required to power the world as a percentage of the global land area, 1.446 × 10 8
km 2 .CSP, concentrated solar power; PV, photovoltaic.
a About 70 percent of the hydroelectric plants are already in place. See Jacobson (2009) for a discussion of apportioning the hydroelectric
footprint area by use of the reservoir.
b The footprint area for rooftop solar PV does not represent an increase in land because the rooftops already exist and are not used for
other purposes.
c Assumes that 50 percent of the wind is over water, and wave and tidal are in water; 70 percent of hydroelectric is already in place; and
rooftop solar does not require new land.
Source: Jacobson and Delucchi (2011).

0.12

6000

V m =7.5 m s -1

Rated power

5000 0.1

0.08

4000

3000 0.06

0.04

2000

1000 0.02

0

0

0 5 10 15 20 25 30 35

0 5 10 15 20 25 30 35

(b) Wind speed (m/s)

(a) Wind speed (m/s)

Figure 13.14. (a) Power curve for an RE Power wind turbine rated at 5,000 kW (5 MW). The curve shows the
power output of the turbine as a function of instantaneous wind speed. The turbine rotor diameter is 126 m,
and the hub height is 100 m above the surface. The cut-in wind speed is 3.5 m s −1 ,therated wind speed is
13 m s −1 ,andthecut-out wind speed is 30 m s −1 .From Archer and Jacobson (2007). (b) Rayleigh probability
distribution of wind speed when the mean wind speed is 7.5 m s −1 .