Table 1

Type Base-load scheme Peak-load scheme Mixed pumped storage scheme
Qin(m3/sec) 600 (24 hr/day) 4800(4 hr/day) 6000 (4 hr /day)
Qout(m3/sec) ——- ——- 1000(20 hr /day)
Number of tunnels 1 5 6
Internal Diameter of tunnel (m) 13 16 15
Thickness of concrete lining (cm) 40 50 50
Thickness of steel plate lining (mm) 14 15 20
Dia.of surge tank (m) 70 72 80
Number of units 2+1 standby 14+2 standby 26+4 standby
Diameter of runner (m) 5.1 5.33 5.85
Width of runner (m) 1.8 1.85 2
Speed N(r.p.m) 80 72 95
Surface level after 100 years (m) – 45.5 -31.38 -70.0
Hydropower generated (109 kwh/year) 1.93 2.2 4.1
Consumed power (109 kwh/year) ——- ——- 21.6
Initial cost(milliard LE) 2.45 17.4 23.3
B/C 1.15 1.074 1.4
IRR % 10.99 10.15 12.57