Cambodia is a very dark place. Most of the country now has acquired some form of electricity as of the last three to five years. According to the World Bank in 2018, 72% of households are connected to the grid; 26% are off the grid, using home solar systems or batteries.
The electricity supply is unreliable. Only 13% of the people have electricity 23 hours a day. 70% face frequent unpredictable power outages. 33% experience damage to their appliances because of voltage fluctuations.
On top of that, electricity is expensive here. Also most buildings were put up before electricity was available and it had to be added later. Thus the lighting in most houses especially is quite minimal.
In the picture above, at a sacristy in a girls school, there is one eighteen-inch fluorescent light above the window and that would be typical lighting for many buildings, even with much bigger rooms.