Sri Lanka has expanded its renewable energy efforts by commissioning the Diyajanani Floating Solar Power Plant, a 5-megawatt (MW) facility installed on the Ibbankatuwa Tank in Dambulla. The plant, connected to the national grid on September 18, covers approximately 10.5 acres and is expected to generate around 9 gigawatt-hours (GWh) of electricity annually. This production capacity could supply roughly 7,500 households, while also cutting diesel consumption by an estimated 2.5 million liters and saving about US$33 million in foreign exchange each year. The project is projected to reduce carbon dioxide emissions by approximately 6,440 tonnes.

Developed by local firm WindForce PLC without foreign consultancy, the floating solar installation uses the Ibbankatuwa Reservoir, chosen for its status as an intermediate reservoir with relatively stable water levels throughout the year. The reservoir receives inflows from Bowathenna Reservoir before water is released onward to Kalawewa. The project highlights Sri Lanka’s move beyond conventional land-based solar farms, which face land constraints due to agriculture, urban development, and conservation priorities. Floating solar arrays also potentially benefit from reduced water evaporation and improved panel efficiency from the cooling effect of water, although these advantages depend on specific conditions.

While Sri Lanka advances floating solar capacity, the rooftop solar sector faces uncertainty following a policy shift announced by the Ministry of Energy. A letter dated September 11 from Acting Energy Ministry Secretary G.M.R.D. Aponsu instructed Electricity Distribution Lanka to end new rooftop solar connections under the Net Metering and Net Accounting schemes, requiring instead that new agreements operate under the Net Plus model. Existing agreements remain valid until their expiration, and feed-in tariffs set by the Public Utilities Commission of Sri Lanka (PUCSL) will not be altered.

Under former schemes, households and businesses installed rooftop solar panels and exported excess electricity to the national grid through various arrangements. Net Metering allowed users to offset future consumption with excess generation credited to their accounts, while Net Accounting involved payments for surplus electricity sold to the grid. The Net Plus approach treats rooftop solar systems more like small power plants, requiring all generated electricity to be sold to the grid and customers paying separately for their consumption. These mechanisms differ mainly in how surplus electricity is credited or compensated.

The change aligns with the National Electricity Policy gazetted in March, which advocates for new rooftop solar agreements under Net Plus and envisages competitive procurement via aggregators or similar mechanisms. The government maintains it is not discouraging rooftop solar but restructuring how electricity from new rooftop installations is integrated and purchased.

However, this shift has elicited concerns from the solar industry and renewable energy advocates. The National Chamber of Commerce of Sri Lanka has urged President Anura Kumara Dissanayake to reconsider the directive, warning it may dampen investment in rooftop solar, increase dependence on imported fossil fuels, and ultimately raise electricity costs. Dr. Lakmal Fernando, the Chamber’s Deputy President and Renewable Energy Sector Committee chair, noted that rooftop solar capacity has reached about 2,600 MW and could help mitigate a projected electricity shortfall of up to 450 MW by early 2027, especially in combination with battery storage.

The Chamber also disputes claims of an oversupplied solar grid, pointing out that Net Plus would still permit solar power to feed into the grid. It called for any major regulatory changes to undergo thorough consultation with PUCSL and highlighted the sector's contribution of over 800 companies and 20,000 jobs. The group warned that weakening rooftop solar could impact maintenance of existing installations and urged restoration of Net Metering and Net Accounting for both current and future prosumers.

The policy change has sparked political debate as well. MP Ajith P. Perera criticized the new directive, drawing a controversial comparison to the September 11 terrorist attacks to underscore what he called ignorance around a program of national importance.

The matter was also discussed at the Committee on Public Finance after Chairman Dr. Harsha de Silva raised it. Officials emphasized that the government is not rejecting rooftop solar but is seeking better integration with the national grid to manage the intermittency of solar generation, which peaks during sunny daytime hours and falls to near zero at night. This variability poses challenges for supply-demand balancing, voltage control, and overall grid stability. One solution discussed is incentivizing battery storage to allow excess daytime solar power to be stored and used during peak demand. Dr. de Silva suggested increasing support to encourage households and businesses to invest in battery systems as these technologies become more affordable.