Siting and Evacuation Advice for a 500 MW Solar Park in Jaisalmer
The Rajasthan government is evaluating a 500 MW solar park on 1,200 ha of revenue land in Jaisalmer district, 18 km from an existing 400 kV substation. The site has global horizontal irradiance of about 5.8 kWh/m2/day, but dust storms reduce module output and water is scarce; the nearest canal outlet is 35 km away. The 400 kV substation has 300 MW evacuation capacity, and a new 400 kV line would need 45 km of right-of-way and at least 30 months. Three villages use part of the land for grazing, and a public hearing is due. The developer proposes 1.5 MW/acre and a 10% water-saving dry-cooling design for a small auxiliary plant. The district administration asks the JE to advise on layout, evacuation and public consultation.
1. Evaluate the land, irradiance, dust and water factors. What would you recommend about using all 1,200 ha?
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The site has strong solar resource, but land and water are not the limiting factors in the way the developer suggests. 1,200 ha is about 2,965 acres. At 1.5 MW/acre, 500 MW needs only about 333 acres, or roughly 135 ha. Using all 1,200 ha at that density would imply about 4,450 MW, far beyond the proposed park and the evacuation capacity.
I would recommend using about 135-200 ha for the module field, leaving the rest for access roads, drainage, buffer zones, substation and inverter yards, and to avoid displacing grazing from the whole tract. The high irradiance of 5.8 kWh/m2/day is favourable, but dust is a major O&M issue. Wet cleaning would be expensive and water-intensive, so the layout should support robotic dry cleaning, and the auxiliary cooling should be dry as proposed. Modules should be sited away from sand dunes and drainage paths, and water harvesting should be included. The park should not consume the entire revenue land merely because it is available.
2. Assess the transmission evacuation problem. What options would you recommend and what studies are needed?
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The existing 400 kV substation can evacuate only 300 MW, so the full 500 MW cannot be commissioned without either curtailment or a new line. The new 45 km line needs at least 30 months, which is longer than a typical module installation period.
My recommendation is to phase the park: commission up to 300 MW first, and build the new 400 kV line in parallel. The remaining 200 MW should be released only after the line is charged and the grid study is accepted. Alternatives such as load-flow rearrangement or a 220 kV temporary evacuation should be considered only if they pass short-circuit, voltage and stability checks; they should not be assumed.
The studies needed are load flow, short-circuit, transient stability, reactive compensation and protection coordination. The park should also provide dynamic reactive support and comply with grid-code requirements. Building 500 MW without evacuation would create avoidable curtailment and weaken the case for future solar investment in the district.
3. Outline the public consultation and land-use process, including safeguards for grazing rights and local concerns.
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The process should begin with identification of affected villages, grazing tracts and village-level institutions, not with a single formal hearing. The district administration should hold gram sabha consultations in the three villages, document the grazing area used, and explain the project layout and compensation.
Safeguards should include:
- avoiding the common grazing land where possible; if it must be used, providing equivalent compensatory grazing land or fodder resources before possession;
- transparent land valuation and compensation, with a grievance committee;
- a public hearing under the environmental clearance process, with notice in local language and adequate time;
- commitments on local employment, water use and dust management;
- a written record of concerns and how each was addressed.
The constitutional and administrative framework includes the Panchayati Raj provisions, Rajasthan land revenue law and environmental clearance requirements. The test is not whether a hearing was held, but whether grazing-dependent households have a workable alternative and whether the project's water and land demands are acceptable to the affected villages.