miércoles, septiembre 28, 2005

Posibles mejoras : Parabolic-trough technology


Oportunidades de mejora para las actuales plantas parabólicas:

Alto porcentaje sobre los costes los supone la estructura.

En el archivo Parabolic-trough technology Roadmap encontrado en la dirección:
http://www.nrel.gov/docs/fy99osti/24748.pdf

Se encuentran entre otros posibles puntos de mejora, los del siguiente fragmento de texto:


  • Advanced Trough Collector
As illustrated above, the structure constitutes about 40% of the solar field cost, whereas the
reflectors and receivers each cost from 20%–25% of the total. In the SEGS design, steel
provides the major strength, with thick glass mirror panels giving the parabolic shape to the
reflecting surface. Lower-cost designs can be explored for the steel structure, with a possible
alternative of a lighter aluminum or composite structure integrated with a front surface
reflector on film, thin glass, or structural member. Evolutionary improvements in the receivers
are also possible.
  • Ø Direct Steam Generation (DSG)
In the DSG concept, steam is generated directly in the parabolic-trough collectors. This saves
cost by eliminating the need for the heat transfer fluid (HTF) system and reduces the efficiency
loss involved with using a heat exchanger to generate steam. DSG should also improve the
solar field operating efficiency due to lower average operating temperatures and improved heat
transfer in the collector receiver. The trough collectors would require some modification due to
the higher operating pressure and lower fluid flow rates. Control of a DSG solar field likely
will be more complicated than the HTF systems and may require a more complex design layout
and a tilted collector. DSG also makes it more difficult to provide any thermal storage. A pilot
demonstration of DSG technology is in progress at the Plataforma Solar de Almería (PSA) in
Spain.

  • The Integrated Solar Combined-Cycle System