Rooftop solar continues to grow and is gaining an increasing share of the solar market; it accounted for 25-30% of new capacity additions in fiscal year 2018-19.

India’s cumulative installed capacity of rooftop solar stood at 4,375 MW at the end of March, with 1,836 MW having been added in fiscal year 2018-19. Of that total figure, commercial and industrial (C&I) rooftops accounted for 3,066 MW, residential 690 MW and public sector installations 619 MW – according to the latest rooftop solar map produced by consultant Bridge To India.

The average solar rooftop system size has increased due to greater adoption by C&I customers, with 29% of the 4,375 MW total made up of systems with more than 1 MW of generation capacity.

Capex vs opex

The capital expenditure (capex) payment model, under which systems are bought and owned by consumers accounted for the majority – 3,055 MW – of rooftop installations.

However, the operating expenditure (opex) alternative – wherein systems are owned and installed by third-party investors – is becoming popular, with its share of installations rising to 37% in 2018-19.

Leading states

Maharashtra has the largest rooftop solar base with 617 MW of generation capacity, comprising 466 MW of industrial systems, 112 MW of commercial and 39 MW of public sector arrays. Rajasthan has 393 MW of rooftop capacity and Tamil Nadu 365 MW.

However, it is Madhya Pradesh and Odisha which have witnessed the fastest growth in rooftop solar over the last three years.

In terms of annual installations, Maharashtra, Rajasthan, Gujarat, Karnataka and Tamil Nadu were the top five states in the last fiscal year, accounting for 60% of the market.

Top players

China’s Delta was the largest rooftop inverter supplier, claiming 19% of the market, followed by Solis (11%) and Swiss company ABB (10%), which this week announced it is leaving the solar business.

Cleantech Solar – with a 13% market share – was the leading solar rooftop developer, followed by Fourth Partner (12.8%) and CleanMax (9.4%).