Why are 600 million Africans still without power?

(CNN)Across 36 African countries, just 2 in 5 people have access to a reliable supply of energy throughout the day, according to a new study by research network Afrobarometer.

Marred by insufficient capacity, poor reliability and high costs, the energy infrastructure in Africa is still problematic, with 25 nations in sub-Saharan Africa facing "a crisis," according to The World Bank.

In some countries - Burundi, Chad, Liberia, Malawi and South Sudan - less than 10 percent of people have access to electricity at all.

Overall, 625 million people are without power in sub-Saharan Africa alone -- that's 68 percent of the population, according to the International Energy Agency.

Huge potential

The continent accounts for 13 percent of the world population, but only 4 percent of the energy demand.

Africa is rich with fossil fuels and renewable resources, but they are not evenly distributed. Only 12 percent of people in Guinea, for example, have an electricity supply that works all the time compared to 100 percent of Mauritians.

The 48 countries that make up sub-Saharan Africa generate roughly the same amount of power as Spain.

But there are signs of improvement: in Ethiopia, access to electricity has risen from 13 percent of the population to 27 percent.

In Nigeria, it's gone up from 45 to 56 percent.

Renewable energy investments are on the rise, and hydropower has a huge unlocked potential: while it already represents one fifth of the overall production, only 10 percent of the estimated potential is being utilized, according to The Wold Bank.

http://edition.cnn.com/2016/04/01/africa/africa-state-of-electricity-feat/index.html?sr=cnnitw