Land management information

Assessment of rooftop photovoltaic solar energy potential in Vietnam

To characterize the suitability of rooftops for the installation of solar panels and to assess the feasibility of deploying solar panels on the most suitable buildings

Project Start
February 2017
Project Duration
16 months

Project conducted for the World Bank


Develop and deploy a cost-effective methodology for assessing the total technical rooftop solar PV across the total building stock in Da Nang and Ho Chi Minh City combining high-resolution stereo satellite imagery, machine learning and human verification to identify suitable rooftops and quantify their potential.


With the support of The World Bank, Vietnam has engaged in the generation of clean and renewable energy. By 2030, the country aims to develop 12 GW of power from solar panels. To support the country towards achieving this target and promoting solar panel adoption, Effigis has implemented a cost-effective solution combining the power of artificial intelligence and satellite imagery, the goal of which was to identify the rooftops that are best suited for solar panel installation in terms of energy potential.

Need for characterization of the suitability of rooftops in Ho Chi Minh City and Da Nang City for the installation of solar panels

  • To assess the rooftop photovoltaic (PV) energy potential in both cities, and extrapolate results across the country
  • To assess the feasibility of actually deploying solar panels on the 250 most suitable buildings
  • To transfer knowledge to authorities, building owners, and developers over the Web
  • Essential criteria for determining rooftop suitability

    Many factors affect how suitable a rooftop is for hosting solar panels. Shape and surface, configuration (such as flat, multisided or curved), roofing, obstructions, accessibility, amount of sunshine, roof slope and orientation, shadows from neighboring buildings and minimum maintenance area contribute to identifying the most suitable rooftops and calculating their potential for energy and power. Not being present in the field to record these parameters is extremely challenging.


    By combining innovative techniques such as ultra-high resolution satellite imagery processing and artificial intelligence with traditional geomatics approaches and information sources, Effigis came up with a methodology and cost-effective solution considering all of the above-mentioned parameters.

    Techniques used in the methodoloy

    • Deep learning (artificial intelligence
    • Photogrammetry
    • Object-oriented classification
    • GIS functions and ground area
    • Image processing
    • Digital surface and digital elevation models

    Sources of information

    • Stereoscopic satellite images
    • Land cover maps
    • Solar atlas

    Results of the assessment

    Effigis reached the conclusion that rooftops of built-up areas in Vietnam have significant potential for generating electricity from solar PV. Industrial and public buildings in urban areas alone account for 25% to 40% of the PV capacity. The broader surface of such rooftops is more suited for solar panel installation than that of small residential buildings, although these account for between 52% and 65% of the PV capacity in urban areas.

    Results, Hô Chi Minh

    ● Potential of 18,000 GWh
    ● 6,6% of the city’s needs would be met by using only 5% of the rooftops, which is consistent with the 6,5% target for renewable energy source by 2020

    Results, Da Nang

    ● Potential of 6,300 GWh
    ● 6,9% of the city’s needs would be met by using only 5% of the rooftops, which is consistent with the 6,5% target for renewable energy source by 2020

    Web-based information portal

    Effigis designed a web portal that displays the calculated rooftop PV solar energy potential in Vietnam. It is a valuable source of information to support Vietnamese policymakers in planning and developing a solar energy industry. Data may be visualized at the commune-level for the entire country, as well as at the commune- or rooftop-level for the cities of Ho Chi Minh and Da Nang. The searchable parameters include the total surface area of each rooftop and each commune, the percentage of suitable rooftops per commune, and the total annual PV energy to be expected from a horizontal surface, an inclined surface or an optimal surface.