Purpose of this Web platform


This Web platform was designed with the purpose of disseminating the parameters that represent rooftop solar PV technical potential in Vietnam. The parameters are provided (1) at the Commune level (for the entire country) and (2) at the rooftop level (for the two cities: HCMC and Da Nang) and comprise:

  • Total yearly PV energy received on a horizontal surface (in MWh/year)
  • Total yearly PV energy received per square meter on a horizontal surface (in MWh/m2/year)
  • Total yearly PV energy received by a tilted surface, inclined and oriented according to rooftop geometry (in MWh/year)
  • Total yearly PV energy received by an optimal (latitude tilted - south oriented) surface (in MWh/year)
  • Total rooftop area of each rooftop (in m2) and each commune (in km2)
  • Suitable rooftop area of each rooftop (in m2) and each commune (in km2)
  • Percent of suitable area of each rooftop and each commune
  • Average of PV power received at noon on a horizontal surface (in MW)


How it was done


The technical rooftop solar photovoltaic potential was determined using the following steps:

  1. Very high-resolution satellite imagery (WorldView-3 30 cm resolution) stereoscopic pairs were used to detect and characterize building rooftops for two cities in Vietnam: Ho Chi Minh City and Da Nang.
  2. The suitable area for the installation of PV systems was determined for each rooftop in these two cities and the solar radiation received on (1) horizontal, (2) tilted (according to the rooftop slope and orientation) and (3) optimal (when slope = latitude and orientation = south) surfaces were calculated. Global solar radiation data (horizontal, tilted and optimal) were obtained from the global solar atlas (http://globalsolaratlas.info).
  3. The technical rooftop solar PV potential calculated using steps 1 and 2 was extrapolated from these results to the entire country. A statistical relationship was established between the suitable area derived from WorldView-3 images for the two cities and the built-up area derived from Landsat-8 images and then used to calculate the suitable area for solar PV system implementation for the entire country.


How to use this platform


Select Area of Interest:

Select between:

HCMC: the results can be explored either at the Commune level (single values for entire Commune or at the Rooftop level (values for each suitable rooftop identified by red dot when zoom is sufficient)

Da Nang: the results can be explored either at the Commune level (single values for entire Commune or at the Rooftop level (values for each suitable rooftop identified by red dot when zoom is sufficient)

Vietnam: the Commune box must be checked to explore the results


Getting information for each Commune at country level:


  1. Select Vietnam
  2. Click on a commune to obtain its individual values for the following variables: PV Horizontal; PV Horizontal/m2; PV Latitude; PV Tilted; Commune total Area; Suitable Area; % Suitable Area; Capacity (electric power) at noon.


Getting information for each Commune:


  1. Select either Ho Chi Minch City or Da Nang
  2. Hover over the individual communes to obtain their respective total Rooftop PV-suitable area in km2 and total PV horizontal in MWh/year. The result will dynamically appear in the top left corner info-box in the map.
  3. Select Variable: PV Horizontal; PV Horizontal/m2; PV Latitude; PV Tilted; Commune Total Area; Suitable Area; % Suitable area; Capacity at noon.


Getting information for individual rooftops:


  1. Select either Ho Chi Minch City or Da Nang
  2. Zoom in sufficiently on area of interest to see caption: "Click on a rooftop to get info" under Rooftops box
  3. Click on Rooftops box
  4. Click on red dot to obtain values for an individual rooftop for PV Horizontal; PV Horizontal/m2; PV Latitude; PV Tilted; Rooftop area; Suitable Area; % Suitable area.
  5. Click on PV Calculator to determine total energy in Wh/m2/year. You will be asked to select the efficiency of the solar panel (standard values between 0.16 and 0.26) and determine the PV type (Horizontal, Latitude or Tilted)


Determining the suitable area of a rooftop for PV system installation


Several criteria need to be examined to determine the suitable area of a rooftop for solar PV system installation. These include: surface area, amount of shading, presence of obstructions, and orientation.

Rooftops with suitable surface areas (after taking into account shading, obstructions and PV system perimeter buffer for maintenance work) less than 10 m2 for residential buildings or 100 m2 for industrial/commercial/public buildings were automatically eliminated.

A rooftop is also rejected if its value for “PV Tilted” is less than 50 % of that of “PV Horizontal”. This means that the rooftop has a slope and/or an orientation that make it unsuitable for PV production.