Page 258 - Alternative Energy Systems in Building Design

234 PASSIVE SOLAR HEATING TECHNOLOGIES

Figure 6.8 Passive parabolic concentrator used in solar electric power–
generating plants.

cloudy periods and are combined with natural gas generation, resulting in hybrid power
plants that provide grid-connected dispatchable power. Solar power–driven electric-
generator conversion efficiencies make CSP technologies a viable renewable-energy
resource in the Southwest. The U.S. Congress recently requested that the Department
of Energy develop a plan for installing 1000 MW of concentrating solar power in the
Southwest over the next 5 years. CSP technologies are also considered an excellent
source for providing thermal energy for commercial and industrial processes.

ADVANTAGES
CSP technologies incorporating storage do not burn any fossil fuels and produce zero
greenhouse gas, NO , and SO emissions. They are also proven and reliable. For the
x
x
past decade, SEGS plants have operated successfully in the southern California desert,
providing enough power for 100,000 homes. Plants with cost-effective storage or
natural gas hybridization can deliver power to the utility grid whenever that power is
needed, not just when the sun is shining. Existing CSP plants produce power now
for approximately 11 cents/kWh (including both capital and operating costs), with
projected costs dropping below 4 cents/kWh within the next 20 years as technology
refinements and economies of scale are implemented. Because CSP plants use rela-
tively conventional technologies and materials (e.g., glass, concrete, steel, and stan-
dard utility-scale turbines), production capacity can be scaled up to several hundred
megawatts per year rapidly.