TY - THES
TI - Wave Energy Distribution Across the Agulhas Bank, A Source of Renewable Energy for a Seawater Pumped Storage Scheme 
AU - Francisco, F
AB - This  study  was  undertaken  to  assess  whether  the  available  and  recoverable  wave  power  density resource  on  the  Agulhas  Bank  (South  Africa)  is  sufficient  to  support  a  Pumped  Storage  Scheme  (PSS). We  used  5  months  of  insitu  wave  data  collected  in  a  depth  of  80  m  off  Cape  Agulhas,  Mossel  Bay, Tsitsikamma  and  Cape  Recife,  together  with  model  wave  data  from  the  National  Centre  for Environmental  Prediction  (NCEP)  -  WAVEWATCH  III  which  was  reanalysed  by  the  French  Research Institute  for  Exploitation  of  the  Sea  (IFREMER)  -  IWOAGA.  The  wave  power  density  resource  (P)  was estimated  by  calculating  the  wave  energy  flux  across  a  unit  diameter  circle  of  the  wave  field,  and  the resource  available  by  the  lateral  transfer  of  wave  energy  along  a  linear  array  of  wave  energy converting  devices.  The  results  showed  that  Cape  Agulhas  had  the  most  available  P  (75%  for  40 kW/m,  25%  for  17  kW/m,  with  an  average  of  31  kW/m)  followed  by  Mossel  Bay  (75%  for  34  kW/m, 25%  for  14  kW/m,  with  an  average  of  25.2  kW/m),  Tsitsikamma  (75%  for  32  kW/m,  25%  for  13 kW/m,  with  an  average  of  25.0  kW/m),  and  Cape  Recife  (75%  for  30  kW/m,  25%  for  12  kW/m,  with an  average  of  23.7  kW/m).  For  the  entire  nearshore  domain,  the  most  frequent  waves  had  values  of  P between  30  kW/m  –  50  kW/m,  with  the  dominant  direction  of  propagation  from  the  southwest.  On average,  the  diurnal  cycle  was  characterised  by  a  peak  in  energy  in  the  evening  nearshore  and  in  the afternoon  offshore.  The  seasonal  cycle  was  characterised  by  a  peak  in  winter  (40  –  50  kW/m)  and trough  in  summer  (20  –  30  kW/m).  The  interannual  variability  signal  had  a  strong  correlation  with regional  Sea  Level  Pressure  (SLP),  surface  westerlies  winds,  and  regional  sea  surface  currents.  It  is also  correlated  to  El  Niño  Southern  Oscillation  (NINO3)  and  the  Southern  Annular  Mode  (SAM).  In terms  of  the  total  annual  wave  energy  resource  (P),  approximately  380  TWh/yr,  are  available  near  the 80  and  128  m  water  depths.  For  the  PSS,  it  was  estimated  that  for  a  moderate  flow  rate  of  50  m3s-1,  the required  power  to  pump  sea  water  to  an  upper  reservoir  with  a  volume  of  5  and  15  million  m3  is approximately  43  and  150  MW.  The  pumping  process  would  take  between  28  and  82  hours.  This  study concludes  that  the  entire  Agulhas  Bank  has  indeed  sufficient  wave  energy  resource  to  supply  a  large scale PSS. 
DA - 2013/01//
PY - 2013
SP - 117
PB - University of Cape Town
UR - https://open.uct.ac.za/bitstream/handle/11427/6585/thesis_sci_2013_francisco_f.pdf?sequence=1
LA - English
M3 - Master's Thesis
KW - Marine Energy
KW - Wave
KW - Human Dimensions
ER -