the utility for managing peak loads that require
energy during the morning and evening peaks
— when there is little or no sun. Thermal energy
storage allows the utility to tailor the electricity
output of a CSP plant to meet that demand.
New regulations and technology advances
have also promoted renewed interest in CSP
during the last five years. Renewable portfolio
standards enacted in many Southwest states
have driven utilities to sign an increasing num-
ber of PPAs with renewable energy suppliers.
CSP offers a quasi-firm power alternative and
excellent power conditioning due to its inher-
ent thermal inertia and thermal storage option.
During the 1990s, when incentives for renew-
able energy dropped dramatically, CSP plant
development stopped. But, at the same time,
the output of the SEGS plants increased with
more efficient components and improved opera-
tions and maintenance practices. Then new com-
Generation from Solar Plant with Storage Can Be Shifted to Match Utility’s Load Profile
mercial developers joined troughs with power
tower and dish-engine options, offering compelling new products and aggressively seeking, and
signing, new PPAs with utilities.
The deployment of CSP systems in Spain
during the last three to four years has become
another driver of CSP growth and operating
experience. These projects have been made possible by sufficient feed-in tariffs (i.e., fixed-price
must-take contracts) offered by the government
for electricity produced by renewable resources.
Spanish regulators capped individual CSP plant
capacity at 50 MW, and the Spanish government
recently set the total capacity under the tariff at
2,400 MW. This capacity is fully committed by
18 CSP project developers whose plants will
come online by 2014. Strengthened by the rapid
development of Spain’s CSP buildup, largely
developed and constructed by Spanish firms,
some of the same developers are establishing
themselves in the U.S. market.
34 May 2010 SOLAR TODAY solartoday.org
Copyright © 2010 by the American Solar Energy Society Inc. All rights reserved.