There are 620 million people in Africa without electricity. Here’s where they live.

The International Energy Agency is out with an in-depth analysis of Africa’s energy sector. One key theme? There are 620 million people in sub-Saharan Africa who don’t have any electricity at all — and fixing that could require burning a lot more fossil fuels:

These numbers are from 2012, and the 620 million in Africa made up about half of the 1.2 billion people worldwide who didn’t have electricity in their homes that year. Here are 9 key points from the IEA report:

1) In some ways, the picture has improved over time. Back in 2000, just 23 percent of sub-Saharan Africa had electricity. In 2012, it was about 32 percent. But the population is growing so rapidly that the total number of people without power has increased.

2) About 80 percent of those without electricity live in rural areas, away from the grid. So at first glance, it might seem like this problem will take care of itself as more people move to cities. But the IEA notes that, unlike other parts of the world, Africa is actually expected to see its rural population grow in the coming years.

3) Even those who do get electricity don’t get a lot of it. Ghana, for instance, had to ration its electricity just to make sure people could watch the World Cup. And the average consumption in sub-Saharan Africa is about 317 kWh per year — or less than a modern American refrigerator.

4) The most popular energy source, by far, is “bioenergy” — mainly the burning of wood, charcoal, and dung. That, in turn, produces a lot of indoor air pollution, which is currently killing millions of people per year:

5) The IEA thinks that the most promising areas of growth in the future are in natural gas and large-scale hydropower. The report notes that Africa still has a lot of untapped hydropower potential — although note that dams can also be hugely controversial in some parts of Africa, particularly when they displace people.

6) Some energy experts have argued that a great way to provide power to rural Africa is through “off-grid” solar panels and wind turbines. The IEA report suggests that there’s something to this. On the one hand, off-grid options are still much more expensive than traditional centralized power plants (see chart below). So for areas that are already connected to the grid or close by, fossil fuels are usually cheaper.

But in places where grid connection is too hard or costly, off-grid solar power and “small wind” are quickly becoming competitive with off-grid diesel generators. That suggests renewables could play a major role in big areas:

7) The IEA sketches out a “new policies” scenario that would involve a major push to electrify Africa between 2012 and 2040, based on existing plans by various countries. Most of the growth in electricity generation would come in hydropower and natural gas, although solar power would also grow significantly:

8) That said, as Alex Trembath of the Breakthrough Institute points out on Twitter, the IEA defines “energy access” as about 50 to 100 kWh per person per year — again, way less than a modern American fridge. So getting the rest of sub-Saharan Africa up to, say, South African levels of electricity consumption would require a much more radical push.

9) The charts above are a good reminder that there’s potentially some tension between reducing global greenhouse-gas emissions and expanding energy access in poorer parts of the world.

Africa needs a lot more energy to lift itself out of poverty. And, right now, fossil fuels are still the cheapest way to do that in grid-connected areas; note that coal plants and gas turbines cost just one-third of what solar panels do. (In rural areas far from the grid, it’s a closer call, and wind and solar power are becoming competitive.) Until clean energy gets significantly cheaper, fossil fuel use is almost certain to rise in the decades ahead.

-- Can the world fight climate change and energy poverty at the same time?

-- Note also that a recent paper in Science projected that Africa’s population could rise faster than earlier forecasts had suggested.

-- The deadliest environmental problem today is indoor air pollution — killing 4 million per year.

-- Ghana had to ration electricity so that everyone could watch the World Cup.