 |
| Titel |
Effect of tidal stream power generation on the region-wide circulation in a shallow sea |
| VerfasserIn |
G. I. Shapiro |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1812-0784
|
| Digitales Dokument |
URL |
| Erschienen |
In: Ocean Science ; 7, no. 1 ; Nr. 7, no. 1 (2011-02-24), S.165-174 |
| Datensatznummer |
250004440
|
| Publikation (Nr.) |
 copernicus.org/os-7-165-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| This paper quantifies the backward effect on the ocean currents caused by a
tidal stream farm located in the open shallow sea. Recent studies in
channels with 1-D models have indicated that the power potential is not given
purely by the flux of kinetic energy, as has been commonly assumed. In this
study, a 3-D ocean circulation model is used to estimate (i) practically
extractable energy resource at different levels of rated generation capacity
of the farm, (ii) changes in the strength of currents due to energy
extraction, and (iii) alterations in the pattern of residual currents and
the pathways of passive tracers. As well as tidal streams, the model also
takes into account the wind-driven and density-driven ocean currents.
Numerical modelling has been carried out for a hypothetical tidal farm
located in the Celtic Sea north of Cornwall, an area known for its high
level of tidal energy. Modelling results clearly indicate that the extracted
power does not grow linearly with the increase in the rated capacity of the
farm. For the case study covered in this paper, a 100-fold increase in the
rated generation capacity of the farm results in only 7-fold increase in
extracted power. In the case of a high power farm, kinetic energy of
currents is altered significantly as far as 10–20 km away from the
farm. At high levels of extracted energy the currents tend to avoid flowing
through the farm, an effect which is not captured with 1-D models. Residual
currents are altered as far as a hundred kilometres away. The magnitude of
changes in the dispersion of tracers is highly sensitive to the location.
Some of the passive drifters analysed in this study experience significant
variations in the end-to-start distance due to energy extraction ranging
from 13% to 238% while others are practically unaffected. This study
shows that both energy extraction estimates and effects on region wide
circulation depend on a complex combination of factors, and the specific
figures given in the paper should be generally considered as first
estimates. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|