Urban Solar

My solar research in Bangladesh can be lumped into two main categories: rural and urban solar. While I am not out tromping through rice paddies, I am trying to understand the market for implementing solar technology in urban Bangladesh, specifically Dhaka. In my last post I discussed the various reasons and lack of infrastructure for why solar home systems make sense for rural areas.  However, it is also possible to make a convincing case for solar in Dhaka. At least, that is what I am attempting to do.

Me on my apartment building's rooftop in Dhaka as 20 solar panels (1kw) are being installed. 

There are two main reasons why residences, factories, government buildings and restaurants are starting to use solar in Dhaka. First, a recent policy was enacted which states that for new buildings in Dhaka, a certain percentage of their energy use must come from renewable sources. Second, although grid electricity exists in Dhaka, currently supply does not equal demand. This results in frequent power outages throughout the city, known as load shedding. These outages can occur anywhere from 1 hour to in the most extreme cases 12 hours a day and are only made worse during the summer months when electricity demand peaks. Due to the power shortages, many buildings will either use diesel generators or IPS systems (often referred to as UPS systems in the U.S., which are batteries that charge using electricity when the current is on) to provide electricity for a few lights and fans per apartment. Generators are noisy and can be quite costly to run and are subjected to fuel price variability, whereas IPS actually put more pressure on the grid since they charge using grid electricity when it is running. 

As a result, these two complementing issues are starting to make solar a viable option for new buildings, first they will install solar so they can get hooked up to the grid and then use the stored solar energy for load shedding hours. The major constraint, however, is rooftop space. Solar panels are not small, and the number needed to power an entire apartment building or restaurant is quite large. Although most buildings have flat roofs in Dhaka, there is only so much space to put solar panels. Moreover, rooftop space is somewhat valuable as it is often times used for drying clothes. Despite spatial constraints, more and more buildings are still finding ways to use solar to for light during load shedding or for lighting common areas such as garages or stairwells. So, in the next few months, I will continue to explore urban solar, trying to figure out the best ways it can be implemented and compare the costs of using solar verse generators and IPS.