According to the MNRE memorandum, the benchmark cost (per Wp) for grid-connected rooftop solar power plants is Rs. 60 for systems above 1 kW, and up to 10 kW capacity. For power plants above 10 kW and up to 100 kW, the benchmark cost is Rs 55; and Rs 53 for those above 100 kW and up to 500 kW.
For standalone solar power plants/packs, the benchmark costs have been categorized into general category states and north-eastern states/hill states and Union Territories (UTs).
While the cost for up to 10 kW capacity six-hour battery backup for general states is Rs. 100/Wp, it is Rs. 110 for the north-eastern/hill states and UTs. The cost for three-hour and one-hour battery backup, meanwhile, is Rs. 80 and Rs. 68, respectively, for general states; and Rs. 88 and Rs. 75 for the second category.
For capacities above 10 kW and up to 25 kW, the cost ranges from Rs. 61 to Rs. 90 for the general category states, and between Rs. 67 and Rs. 99 for 6/3/1-hour battery backup for other states and UTs.
The states have also been classified under two categories for solar lighting systems and solar pumps. For the latter, the benchmark costs per horsepower (HP) have been fixed at Rs. 85,000 for up to 3HP DC, and Rs 80,000 up to 3HP AC in the general category. For North-eastern/hill states and UTs, the cost is Rs. 93,500 for up to 3HP DC, and Rs. 88,000 up to 3Hp AC.
For solar lighting systems, the new general states category cost is Rs. 250/Wp for solar lamps, Rs. 300 for solar street lights with lead acid batteries, and Rs. 435 for solar street lights with lithium-ion batteries. The benchmark cost for north-eastern/hill states and UTs is slightly higher for both solar lamps and solar street lights.
The new benchmark costs are inclusive of total system costs, installation, commissioning, transportation, insurance, five-year AMC/DMC, and applicable fees and taxes.
Worldwide, benchmark costs are falling. According to the United States’ Department of Energy’s (DoE) SunShot initiative, the country has already achieved its 2020 goal of utility-scale solar PV power at US$0.06/kWh.
SunShot’s 2030 goal for utility-scale solar PV is $0.03/kWh, which is 71% lower than the 2010 benchmark cost. Goals for commercial solar ($0.04/kWh) and residential solar ($0.05/kWh) are 68% less than the current benchmark cost.
A recent cost analysis report by the International Renewable Energy Agency (IRENA), meanwhile, states that worldwide Solar PV electricity costs have fallen 73% since 2010, and that the cost is expected to cut in half by 2020. By 2019, the best onshore wind and solar PV projects will be delivering electricity for an equivalent of 3 cents/kWh, or less.