Urban Solar

Transmission of Power

Africa has recently gone through an economic renaissance with economic growth in double digit figures in many states. The populations are also booming, and they are moving to the cities; Uganda’s urban population is projected to increase from 6 million in 2013 to over 20 million in 2040. As any Kampala resident will tell you, the city is struggling to provide services to the current population. So, a key question is, can the economy keep pace with the population growth?

Kampala by night

Kampala by night

Solar In the City

Access to electricity boosts economic growth (link) and as the world moves away from fossil fuel sources, renewable energy is advancing at breakneck speed. Multiple massive and micro hydro-electric projects are underway in Uganda (link one & two). The solar home system (SHS) market has many players trying innovative ways to deliver power to rural markets. Still, only 15% of people have access to electricity and 55% of these reside in urban areas.

Renewable energy in the urban environment makes complete sense especially for African cities with the abundance of roof top space with many of these building’s being flat roofed, an ideal environment for solar PV panels. This renewable energy solution can be rolled out on a massive scale that is cost effective for African cities. As always though, Data is King and a fair amount of energy planning is required not to mention proper feasibility studies to ensure maximum solar output.

Geo-Feasible

GIS or Geographical Information System’s come into play here by looking at different variables that impact solar generation. GIS can provide an indication on the amount of ideal roof space available for PV generation. From here by establishing the solar irradiation for that specific location one can calculate the annual solar output based on the amount of feasible roof space in the city environment. This can then be taken a step further by using satellite data on atmospheric conditions such as air pollution levels and climatic data, air quality impacts the amount of electricity generated. During periods of cloudy weather or high levels of air pollution with limited sunlight photovoltaic panels produce less electricity. The terrain of the area such as surrounding hills, tree’s and buildings create shading that changes throughout the year depending on the sun’s azimuth, GIS data can also provide this data. Again, any shading will negatively impact a photovoltaic panel’s electricity output.

By taking all this data into account one can accurately model a roof top PV system or multiple systems across an urban environment with limited effort and cost thereby reducing costly site surveys on a site by site basis. The value GIS data can provide the urban solar environment is immense and there exists a lot of potential for using this technology in Africa. Cities around the world have already this approach with great success in energy planning.

A GIS analysis of the solar potential of each building in central division of Kampala

A GIS analysis of the solar potential of each building in central division of Kampala

We did this analysis for each building in the central division of Kampala, Uganda. The results were excellent. Details to follow but hopefully this graphic will satisfy you for the moment.