According to the recent BP Statistical Review of World Energy 2020, globally, renewables account for 10.4 per cent of power generation. In India, in 2019-20, renewables, excluding large hydro, accounted for around 10 per cent of electricity generation (as opposed to installed capacity) and within this, solar accounted for 3.6 per cent, contributed mostly by utility scale solar PV such as solar parks, whereas the share of rooftop PV was negligible.
Rooftop solar PV is a low-hanging fruit. Recognising this, the Centre has set a target of 40 gigawatts by 2022. Yet, by September 2019, India had reached a rooftop solar capacity of only 349 MW, of which Karnataka alone accounted for 240 MW, set up mostly by institutions and government offices, rather than individual homeowners, which is disappointing for a tropical country enjoying more than 300 days of sunshine.
The proliferation of high-rises in cities is certainly a factor in the lukewarm response to the solar rooftop PV programme. That apart, despite the generous capital and interest subsidy offered under Central and State schemes for installation of rooftop PV, homeowners have been reluctant to adopt this technology although it could slash their power bills. There are many factors behind this reluctance.
Standalone off-grid solar PV is favoured in remote, unconnected areas. The rest are envisaged to be connected to the grid, obviating the need for installing batteries for storage, giving the homeowner the flexibility to draw power at any hour, even when the sun does not shine. Rooftop PV homeowners are referred to as prosumers