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February 16, 2026
Struggling to break through: the state of rooftop solar in Indonesia
What satellite imagery reveals about small-scale solar PV installation rates in Southeast Asia’s largest coal system
Summary
Indonesia’s rooftop solar market remains small despite strong solar resources, reflecting structural constraints in a power system dominated by a young and extensive coal fleet.
Using satellite imagery and an enhanced sampling and extrapolation methodology, TransitionZero estimates Indonesia’s installed rooftop solar capacity at around 479 MWac (~600 MWp) by end-2025, broadly in line with official disclosures but well below national targets.
Deployment is highly concentrated in Java, with negligible uptake elsewhere, placing Indonesia well behind regional peers and underscoring the contrast in rooftop solar adoption across Southeast Asia.
Indonesia: sunshine without scale
It is no secret that Indonesia remains the most complex and challenging energy transition market in Southeast Asia. Despite abundant solar resources, cheap and scalable solar power has struggled to gain traction in a power system structurally dominated by the largest — and one of the youngest — coal fleets in the region.
As Indonesia continues to grapple with the economic and institutional challenges of phasing down coal and creating space for clean energy alternatives, the status of its rooftop solar market warrants closer examination. Rooftop solar is not explicitly reported in the Ministry of Energy and Mineral Resources (MEMR)’s annual energy handbooks, and official disclosures remain infrequent. In parallel, TransitionZero’s Solar Asset Mapper tool has identified large rooftop solar systems in Indonesia, though coverage is not exhaustive.
Regional experience suggests that self-consumption and behind-the-meter rooftop solar systems is being quietly deployed by consumers and contributing to decarbonisation. This article presents our assessment of Indonesia’s rooftop solar penetration using TransitionZero’s enhanced methodology for estimating small-scale rooftop solar. We also take a comparative view of deployment levels and market characteristics across Southeast Asia.
Our methodology: structured, cost-effective, and repeatable
TransitionZero’s Machine Learning team has developed an in-house methodology to estimate distributed and rooftop solar development in markets where such systems are potentially a significant driver of capacity growth. The approach was first deployed in an analysis of rooftop and ground-mounted distributed solar in Pakistan, and has since been applied to three Southeast Asian markets: Vietnam, Malaysia, and Thailand.
This same methodology has now been applied to Indonesia, and offers a structured and cost-effective way to assess the market’s rooftop solar landscape. In addition, it can be repeated over time to track deployment trends, policy impact, or market appetite.
In Indonesia, our reference point is MEMR’s announcement that the country’s installed rooftop solar capacity reached 538 MWp as of June 2025, with a target of 1,000 MWp by year-end, something our analysis aimed to validate.
Our methodology is based on a sample of high-resolution imagery, as acquiring such imagery for the entire Indonesian archipelago would be prohibitively expensive. Instead, we purchased detailed images for selected representative areas across Indonesia. Approximately 1,750 images were procured and analysed, around 80% of which were taken in the 12 months leading up to December 2025.
The sampling was focused on Java, Indonesia’s most densely populated region, and the recency of imagery allowed us to capture developments more recent than those reflected in MEMR’s June 2025 statistics.
Within these samples, solar installations were identified and labelled, after which installation patterns were analysed by building size, region, and urban or rural setting. These labelled datasets were then used to construct an extrapolation model estimating rooftop solar capacity at both national and regional levels.
The detailed technical methodology can be found here.
What we found
The results were mapped using a hexagonal grid to visualise the spatial distribution of rooftop solar capacity across Indonesia. In the heatmap, taller, darker hexagons represent areas with higher estimated rooftop solar capacity, with the values adjusted to improve visual differentiation.
Following this methodology, we estimate 479 MWac (~600 MWp) of installed rooftop solar capacity in Indonesia as of the end of 2025.
This estimate is broadly in line with MEMR’s June 2025 disclosure of 538 MWp, and suggests that while rooftop solar deployment continued in the second half of the year, it was insufficient for Indonesia to meet its cumulative 1,000 MWp target by end-2025.
To account for uncertainties such as labelling confidence, panel efficiency, sampling bias, accuracy of external datasets and panel tilt, we estimate an error margin of 16%. This yields an estimated range of 400 - 560 MWac of total rooftop solar capacity nationwide. For comparison, this gives an estimated upper bound of 696 MWp, still a long way short of Indonesia’s ambitious 1,000 MWp target.
The table below shows the estimated regional breakdown. Unsurprisingly, 87% of rooftop solar deployed to date is concentrated in the Java region, with negligible development detected elsewhere in the country.
Due to the very low levels of rooftop solar detected relative to other regional markets, we are unable to produce a reliable residential versus commercial & industrial split for Indonesia.
A Southeast Asia recap
As we conclude our Southeast Asia rooftop solar research with Indonesia, we take the opportunity to assess the regional landscape based on TransitionZero’s findings.
Our data project covered the four largest power markets in Southeast Asia, namely Vietnam, Malaysia, Thailand, and Indonesia. This focus was due to data gaps in official statistics and a broader assessment that these are, or are likely to become, meaningful adopters of rooftop solar thanks to ongoing regulatory reforms and rising consumer interest.
Our methodology is validated by the fact that, when available, our estimates broadly align with official figures – consistently coming in slightly higher than released statistics. This points to the recency of our research, compared to other sources, and the additional coverage of off-grid, behind-the-meter systems that are often not captured in official numbers. This is further confirmation that a methodology of informed sampling, analysis and extrapolation, even with limited geographical coverage, is a viable strategy for producing aggregated rooftop solar estimates.
At the same time, our analysis extends beyond national reporting by providing sub-national estimates that highlight regional hotspots, as well as deployment by consumer segment, including residential versus commercial and industrial systems, in markets with high rooftop solar penetration.
Placed within the regional regulatory and market context, our findings suggest that rooftop solar uptake in Southeast Asia is driven primarily by strong consumer interest, particularly from the C&I sector, in regions with high levels of industrial activity and favourable solar resources. In addition, an enabling regulatory framework that permits and facilitates installations, even self-consumption and behind-the-meter systems without explicit grid revenue mechanisms, has been critical to driving and sustaining rooftop solar adoption in key markets such as Vietnam and Thailand.
Finally, based on the data collected, we also identified rooftop solar installation patterns across the markets. Vietnam outperforms its peers by a significant margin in deployment rates across all rooftops larger than 1,000 square metres. By contrast, Thailand leads the region in installations on smaller rooftop areas, suggesting relatively higher uptake and larger sized panels and systems in residential and smaller commercial premises.
What’s next?
As the final stop of this data project, we turn our attention back to South Asia with the release of our assessment of Bangladesh in the coming weeks. Stay tuned!
This is part of a series of blogs presenting our findings on the status of rooftop solar deployment in Southeast Asia and South Asia. Check out our earlier blogs on Pakistan, Vietnam, Malaysia and Thailand, and stay tuned for the upcoming analysis featuring Bangladesh.
