Effects of solar floating platforms on the hydrodynamics and the ecosystem of a coastal Sea
Karpouzoglou, T. (2019). Effects of solar floating platforms on the hydrodynamics and the ecosystem of a coastal Sea. MSc Thesis. IMAU (Institute for Marine and Atmospheric research): Utrecht. 74 pp.
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| Abstract |
The effects of floating photovoltaic (PV) installations on the hydrodynamics and the ecodynamicsof a coastal sea as the North Sea, are analysed with a coupled physical-biogeochemical 1Dcolumn model (GOTM-ERSEM-BFM). The model is calibrated and validated with the use ofSmartbuoy observations from three locations in the North Sea. The equations of the model arealtered as to include four different effects (ef) of the PV installations, namely: ef1) decreasedlight conditions due to the shadowing effect of the platforms, ef2) reduced wind stress due tothe limitation of the free surface of the water column, ef3) introduction of an additional surfacestress experienced by currents, due to friction induced by the platforms, ef4) reduced waveheight due to the presence of the platforms. The 1D model is capable of reproducing the mainseasonal patterns of ecosystem variables such as chlorophyll a, with performance comparableto a 3D model. Moreover, it proves to be more efficient in open-sea locations where horizontaladvection is of less importance. Regarding the individual effects, ef1 is the dominant one.However, some ecosystems may reveal resilience to ef1 for small percentages of coverage. Theeffect of ef2 on the hydrodynamics and the ecosystem is small in locations with strong tidalcurrents. This effect can be very important for stratified locations due to its impact on the topmixed layer and thus on primary production. The ef3 can be important for the ecosystem oflocations with strong currents. This is evident for small percentages of coverage where ef3 leadsto a minimum of suspended sediment near the surface (and maximum of irradiance). The ef4reduces strongly the concentration of suspended sediment in the water column. However, thereduction occurs mainly at lower depths and out of the photic zone, leading to no significantchanges in the light availability of the ecosystem. Overall, the shadowing effect (ef1) of theplatforms on the ecosystem is the most important. However, for the case of well mixed locationswith high concentration of suspended sediment near the surface, ef1 is partly compensated bythe effect of reduced turbidity that follows the other three effects. This is more prominent forsmall percentages of coverage where ef3 is of comparable importance to ef1, resulting in nosignificant overall impact of the PV installations on the marine ecosystem. Concluding, wellmixed locations with high currents and large concentration of suspended sediment near thesurface are more favorable to the installation of a solar power plant. However this statementis restricted by the assumption that the power plant wont occupy more then 20% of the 1Ddomain. |
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