In a telling testimony to the viability of rooftop solar in the residential sector, an apartment complex in Bengaluru has opted for the third phase of its rooftop solar project after the success of its first two phases over the last two years.

The Westend Heights Condominium Apartment Owners Welfare Association has now invited bids to install 105 kW of rooftop solar capacity. In the first phase in September 2021, the condominium complex had installed 185.4 kW, followed by 100 kW in the second phase in October 2022.

The deadline for bids is April 9, 2023. They would be opened on the same day.

The solar panels installed on the sprawling condominium roof space spread over 19 towers and 1,830 flats are already yielding a savings of about ₹350,000 (~$4,262) a month on power bills for its residents, Kartikeya Khanna, secretary of the residents’ welfare association, told Mercom.

The condominium, which has also implemented energy-saving measures while embracing rooftop solar, consumes about 100,000 units of electricity a month, down by 30,000 from five years ago.

It issued a tender for 165 kW in January 2021 and followed it up with bids for 150 kW last April.

When the third phase is up and running, the association claims it will have one of the largest rooftop solar capacities in the residential segment at 390 kW.

The residents were sold on the idea of the savings on electricity bills rooftop solar would bring and the fact that they would be giving back to society by opting for clean energy.

“We didn’t face any resistance from the flat owners when we proposed the idea. Even before we went for rooftop solar, we replaced fluorescent tube lights with LEDs and installed motion-sensing lights. So we were conscious of the benefits of optimizing our energy usage,” Khanna said.

CAPEX Model

The condominium complex opted for the capital expenditure model, considering the attractive return on the cumulative ₹20.2 million (~$277,672) investment for all three phases of the rooftop project. The project started earning from day one, thanks to the net metering arrangement with Bangalore Electricity Supply Company (BESCOM).

Power from the project is used for lighting common areas, and running the elevators, the sewage treatment plant, and the water pumps.

The residents’ association systematically went about the rooftop solar projects by engaging a consultant to baseline the capacity requirement before calling for bids.

“We didn’t take the quotation route as some other residents’ welfare associations (RWA) did and failed,” said Khanna.

The bidding process also ensured it got attractive operations & maintenance packages from the installers.

Like in the first two phases, the scope of the tender for the third phase includes the design and layout of the rooftop solar system, including all civil, structural, electrical, and related works, supply of materials, and installation of commissioning.

Rooftop Solar in Urban Areas

The Westend Heights success story has important lessons for other RWAs to emulate. According to Khanna, rooftop spaces on apartment complexes have no value.

“Instead of letting these spaces go waste, putting up solar panels will not only save money on power bills, but the residents would also have given something back to society by opting for clean energy,” he said.

Khanna said distribution companies have an obligation to support RWAs and make it easier for them to adopt solar. He was, however, not too happy with BESCOM, which put roadblocks in the approval process of inverters.

“The tortuous inverter empanelment process must be done away with, as also the 50 kW cap per Low Tension meter,” he said.