Em termos energéticos, África é o continente mais "renovável" do mundo. No mundo rico, as energias renováveis representam menos de um décimo do fornecimento total de energia. Os 900 milhões de pessoas da África Sub-Saariana (excluindo a África do Sul) recebem 80% da sua energia a partir de fontes renováveis.
 

It is almost universally agreed that more education is good for society. But it turns out that some popular educational policies achieve very little, while others that are often overlooked can make a huge difference.

Reducing class sizes would seem to be an obvious improvement; but by itself, smaller class size has not been shown to boost educational performance. Likewise, extending the school day seems an easy way to ensure that pupils learn more; but research finds that time spent in school matters considerably less than what happens there.

Es gibt ein fast universelles Einverständnis darüber, dass mehr Bildung gut für die Gesellschaft ist. Aber es gibt öffentliche Bildungsmaßnahmen, die sehr wenig erreichen, während andere, die sehr viel bewirken können, oft übersehen werden.

Existuje téměř všeobecná shoda, že víc vzdělanosti je pro společnost přínosem. Ukazuje se ale, že některé populární vzdělávací politiky přinášejí velmi málo, zatímco jiné, často přehlížené, mohou změnit mnoho.

Jasným zlepšením by se zdálo zmenšení velikosti tříd, ale nižší počet žáků ve třídě se sám o sobě neprojevil jako vzpruha výsledků vzdělávání. Rovněž prodloužení školního dne se jeví jako snadná cesta k zajištění, aby se žáci víc naučili; výzkum ale zjišťuje, že čas strávený ve škole je podstatně méně důležitý, než co se tam děje.

Bangladesh has had incredible success fighting hunger. In 1990, almost two-thirds of children younger than five were underweight, but less than one-third are today. Recently, Bangladesh even received a “special recognition” award from the UN's Food and Agriculture Organisation for outstanding progress in fighting hunger and poverty.

Over recent decades Bangladesh has seen amazing improvement across many health indicators. Maternal mortality has decreased 75 per cent, infant mortality has halved, and life expectancy has surpassed that of both India and Pakistan. The progress has been so impressive that in 2013 The Lancet, one of the oldest and most prestigious medical journals in the world, devoted a six-part series to Bangladesh, calling it "a remarkable success story for health."

Every government minister, senior civil servant or charity official is familiar with the pitch. Spend money on my project, says the supplicant: it will bring such large benefits that you will actually save money in the long run. At this, the official sighs, knowing that another supplicant with an equally bold pitch is waiting outside. How can he pick among competing pleas for bridges, IT systems, deworming medicines and a thousand other things?

This week, at a conference in Dhaka, the Copenhagen Consensus will try to answer that question, reports the Economist.

Dhaka is one of the fastest-growing megacities in the world. A population of just 3 million in 1971 has ballooned to 18 million today. This unprecedented urban growth has resulted in a city more densely inhabited than Tokyo, Shanghai, Mumbai, or any other major city (Robert Gallagher).

The capital's growth partially represents the progress of the Bangladesh economy, which has grown atover 6 percent annually (7th Five Year Plan). The city's transport system, however, hasn't kept up, and Dhaka now has some of the worst traffic congestions in the world.

ast week, a study in the prestigious journal Nature revealed just how much CO₂ increases have greened the Earth over the past three decades. Because CO₂ acts as a fertilizer, as much as half of all vegetated land is persistently greener today. This ought to be a cause for great joy.

Instead, the BBC focused on warning that the paper shouldn’t make us stop worrying about global warming, with threats like melting glaciers and more severe tropical storms. Many other major news outlets did not even report on the study.

It seems like a great idea: to improve education in Bangladesh, we should equip classrooms with computers, moving the next generation to the cutting edge of knowledge. But while such an idea is alluring and has gotten wide traction around the world in the last decade, we need to look at the evidence. And it is surprising.