By Francis Allan L. Angelo

The payback period for residential rooftop solar in the Philippines fell from 4.0 years in May 2025 to 3.1 years in May 2026, according to a new analysis by independent energy think tank Ember.

Ember attributed the accelerated return on investment to a 10% decline in solar installation costs and surging retail electricity prices.

Commercial rooftop solar payback times dropped from 3.0 years to 2.3 years over the same 12-month period, Ember reported.

The think tank noted that industrial rooftop payback timelines similarly decreased from 3.9 years to 3.1 years.

Ember’s data shows Meralco’s retail electricity prices in May 2026 were 17% higher for residential customers compared to the previous year.

Meralco’s commercial rates rose by 18%, while industrial rates increased by 14% year-over-year.

The Philippines now has the costliest residential electricity price in Southeast Asia, according to Ember’s review of Department of Energy figures.

The country also holds the second-highest commercial price and the third-highest industrial electricity price in the region.

Meralco, which distributes about 55% of the electricity billed in the Philippines, avoided an even higher price hike in May 2026 after the Energy Regulatory Commission intervened to prevent a 4% rise in generation costs.

“The economics of rooftop solar are more attractive than ever, and its rapid rise is inevitable,” said Dave Jones, chief analyst at Ember and lead author of the report.

“The government has an opportunity to carve its own path on rooftop solar, to pull the Philippines out of fossil dependency and onto a path of cheap, abundant electricity,” Jones said.

Ember estimates that rooftop solar capacity in the Philippines nearly doubled from 721 megawatts (MW) in early 2025 to approximately 1,300 MW by early 2026.

This installed capacity still represents only 1% of the country’s theoretical rooftop potential of 106,000 MW, according to the Institute for Climate and Sustainable Cities (ICSC).

The ICSC measured 712 MW of rooftop solar using satellite images up to January 2025, comprising 371 MW for residential, 214 MW for commercial and industrial, and 136 MW for rooftops over 1 MW.

Ember’s analysis of generation data from the Independent Electricity Market Operator of the Philippines (IEMOP) shows grid generation falling sharply at midday when solar output peaks.

The IEMOP data suggests the country added around 600 MW of rooftop solar between April 2025 and April 2026.

Official tracking lags behind private analysis, with the Department of Energy reporting 3,765 MW of grid-connected solar as of March 2026, of which 99% is ground-mounted and only 1%, or 52 MW, is behind-the-meter capacity.

The Energy Regulatory Commission’s latest public update from May 2025 showed only 157 MW of cumulative net metering capacity.

Net metering, introduced under the Renewable Energy Act of 2008, allows customers with solar systems of up to 100 kilowatts to export excess power to the grid in exchange for bill credits, but registration has historically been slow and paperwork-heavy.

The International Energy Agency previously estimated Philippine rooftop capacity at 200 MW by the end of 2025.

Ember highlighted that the Philippines imported 5,068 MW of solar panel capacity in 2025, more than five times the 800 MW of grid-connected utility-scale solar installed that year.

The total value of net solar panel imports rose from USD 365 million in 2024 to USD 483 million in 2025, driving a 62% rise in capacity from 3,130 MW to 5,068 MW.

China supplied 98% of these 2025 imports, while 14% of the value was re-exported, primarily to the United States starting in September 2025.

In the first quarter of 2026, Chinese solar panel exports to the Philippines reached 3,200 MW.

Ember noted a massive surge in March and April 2026 alone, with China exporting over 3,000 MW of solar panels to the Philippines.

The think tank confirmed the Philippines is now China’s second-largest solar panel export market for the year, ranking ahead of Pakistan.

Ember pointed out that Pakistan currently has an estimated 32 gigawatts (GW) of rooftop solar, though 85% remains unregistered.

China also exported USD 292 million worth of solar cells to the Philippines between October 2025 and March 2026, equating to 6,628 MW of capacity.

Domestic manufacturing is scaling up, with Gstar opening a 1 GW plant in Subic Bay in May 2025 and a second 1 GW facility at the First Philippine Industrial Park in April 2026.

A 0.37 GW solar manufacturing investment was also signed in Batangas in April 2026.

“The supply of panels is already on the ground. The economics are already there. Consumers are keen. Even back in 2024, 82% of surveyed households expressed some interest in adopting solar panels,” Jones added.

Ember envisions the deployment of 3,500 MW of rooftop solar paired with 4,500 megawatt-hours (MWh) of battery storage within 24 months.

This proposed capacity matches the scale of the Meralco Terra Solar project.

At the latest installed battery price of USD 125 per kilowatt-hour, Ember estimates the total project cost would be approximately USD 560 million.

Ember asserts this is a cheaper alternative to new coal plants, which BloombergNEF estimates at USD 87 to USD 117 per MWh, compared to USD 55 to USD 80 per MWh for firmed solar calculated by the International Renewable Energy Agency (IRENA).

IRENA reports that solar and batteries in sunny countries can provide electricity for 95% of the year.

Ember emphasized that rooftop solar can directly reduce reliance on imported gas, noting that 60% of Meralco’s supply is natural gas, almost all of which is U.S. dollar-denominated liquefied natural gas.

Imported solar panels cost USD 0.15 per watt and last 20 years, making them 20 times less import-intensive than gas priced at USD 17 per million British thermal units (MMBtu).

Ember indicated that Philippine electricity use per capita is half the ASEAN average due to chronically high prices.

The think tank added that cheaper rooftop electricity could support the country’s growing electric car sales, which lag behind the rest of the ASEAN region.

Ember’s economic payback models assume a residential system price of PHP 60 per watt, equivalent to USD 0.98 per watt.

Commercial and industrial payback calculations assume a lower system price of PHP 40 per watt, or USD 0.66 per watt.

These models rely on a 15.4% load factor, producing 1,350 kilowatt-hours annually per kilowatt of direct current.

To unlock this mass scale, Ember recommends expanding loan schemes like the Government Service Insurance System’s (GSIS) Ginhawa Solar Energy Loan (GSEL) program.

The think tank suggests offering this financing framework to the country’s roughly 40 million private sector workers.

The GSIS currently offers its 2 million government employees a loan at 5% interest, repayable over five years.

Ember reported that 46% of the PHP 12.5 billion GSIS loan pot was drawn in just 27 days, generating applications for around 95 MW of solar totaling PHP 5.7 billion.

Ember’s second policy recommendation is to enable smaller plug-and-play solar through a micro-generation exemption for systems below 800 watts.

This exemption would mirror Germany’s balcony solar framework, which has 1 million installed systems totaling 1,000 MW, complementing more than 4 million standard rooftop setups.

German supermarkets sell such plug-and-play kits for roughly EUR 200, cutting the per-watt cost almost in half and reducing the payback time to well under two years.

Currently, the Energy Regulatory Commission classifies connecting a microinverter to a wall socket without net metering registration as an illegal “flying connection.”

Ember’s third suggestion is a government project to build battery storage distributed across roughly 45 sites of 100 MWh each.

The think tank notes each of these battery sites would require a land footprint of fewer than twenty 20-foot containers.

Ember welcomed recent government policy changes that have streamlined the solar installation process.

In early 2026, the government reduced net metering approvals to 10 days and shortened electrical permit issuances to three working days.

Regulators also introduced multi-site and aggregate net metering in February 2026.

Updated Retail Competition and Open Access regulations will allow customers with over 100 kilowatts of demand to enter solar power purchase agreements starting in June 2026.

Additionally, the November 2024 CREATE MORE Act changed business tax rules on expense deductions to make rooftop solar more attractive.

Ember noted that a controlled burst of solar and batteries would avoid the chaotic rise seen in Pakistan, the sudden halt of Vietnam’s boom, or the slow pace of Indonesia’s 100 GW village-scale plan.

“Rooftop solar has two key advantages over wind and utility solar: it is built in days, not years, and with batteries, it reinforces the grid rather than stretching it,” Jones said.

“The government’s plans to speed up renewables auctions will help avoid a future energy emergency. Rooftop solar can help do that even faster,” Jones concluded.