Memoranda of Understanding (MoUs) have been signed by the state government and SJVN to build the two projects.

Four years ago the development option for Luhri was allocated to the utility to undertake planning work and produce a detailed project report (DPR). It is to be built downstream of the 412MW Rampur plant and commissioned by mid-2015.

Earlier studies proposed that the plant have an installed capacity of 465MW but a proposed alternative dam site would enable SJVN to benefit from 90m of additional head. Over the last year, from when the plant was planned to have an installed capacity of 700MW, the design has gone through further changes, not least adding an extra 75MW.

In stepping up the total capacity, the design has also changed the numbers and size of units. Luhri is have four units of 193.75MW capacity compared to the earlier plan for six units of 116.67MW.

The flow rate is almost the same, 480m3/sec compared to 477m3/sec but the net head has increased to 181m from 162m.

While noted as a run-of-river development, the proposed scheme will have a 86m high concrete gravity dam, although that was previously expected to be 78m high. The project will also involve construction of a 38.1km long, 9m diameter circular headrace tunnel, which was previously envisaged as 29km long and 10.5m wide.

The dimensions of the underground powerhouse have also changed, altering to 156.4m by 23.5m by 44m from the earlier concept of 131m by 24m by 47m.

The tailrace tunnel will be 9m diameter, circular, compared to a 10.50m wide horseshoe-shaped conduit of the earlier design. The length has increased to 454m from 250m.

Part funding for the project is to come from the Government of India and the state Government of Himachal Pradesh, which together own SJVN. Previously, the base cost for the project was estimated at Rs 3657 Crore at mid-2005 prices (US$840M in 2005, now US$770M due to currency effects). The latest stated budget is Rs 4795 Crore, estimated at the end of 2006 (US$1.06B in late 2006, now US$1B). The estimated cost does not include financing charges.

The 40MW Dhaulasidh plant is to be built on the river Beas near the village of Sanotu, near to Nadaun in Hamirpur District.

Dhaulasidh will require construction of a 130m long gravity concrete masonry dam capable of discharging 13,335m3/sec. A powerhouse will be built at the dam toe and will hold two 20MW units.