Table 1: Key statistics

Installed capacity 690MW
Annual electricity production Approx. 4600GWh
Turbines 6 Francis vertical axis
Rated discharge per unit 24m3/sec
Rated output per unit 115MW
Hlsln reservoir area 57km2
Hlsln reservoir length 25km
Hlsln reservoir live storage 2100Mm3
Hlsln full supply level (FSL) 625m a.s.l.
Hlsln minimum operating level 575m a.s.l.
Hlsln catchment area 1806km2
Average inflow to Hlsln 107m3/sec
Krahnjkar dam maximum height 193m
Krahnjkar dam length 730m
Krahnjkar fill materials 8.5Mm3
Desjarr dam maximum height 60m
Desjarr dam length 1100m
Desjarr fill materials 2.8Mm3
Saudrdals dam maximum height 25m
Saudrdals dam length 1100m
Saudrdals fill materials 1.5Mm3
Ufsarln reservoir area 1km2
Ufsarln maximum water level 625m a.s.l.
Ufsarln pond catchment area 430km2
Average inflow to Ufsarln 31m3/sec
Ufsar dam maximum height 37m
Ufsar dam length 620m
Ufsar fill materials 0.6Mm3
Keldurln reservoir area 7.5km2
Keldurln FSL 669m a.s.l.
Keldurln live storage level 60Mm3
Keldur dam maximum height 26m
Keldur dam length 1650m
Keldur fill materials 0.8Mm3
Tunnels Approx. 72km
Headrace from Hlsln (dia: 7.27.6m) 39.7km
Headrace from Ufsarln (dia: 6.5m) 13.3km
3 adits to headrace (dia: 7.27.6m) 6.9km
2 diversion tunnels and adit at dam 2.4km
Grouting galleries at dam 0.5km
Surge tunnel (dia: 4.5m) 1.7km
2 diversion tunnels Hraunaveita (dia: 4.5m) 3.7km
2 vertical pressure tunnels (dia: 4.0m) 0.8km
Access tunnel to power station (dia: 7.5m) 1.0km
Tailrace tunnel (dia: 9.0m) 1.3km
Cable tunnel (dia: 4.0m) 1.0km
Total head 599m
Maximum rated discharge 144m3/sec
Average discharge 110m3/sec