It can mean the gas at an entire building is shut off, leaving residents unable to use a stove for months until expensive repairs are made to gas lines. So Yaker was all in when he learned of a ...

For several months now, Suzanne Noubissie, a housewife in Douala, Cameroon's economic capital, has been swapping her coal-burning stove for one that uses a recycled oil. The device, designed by a ...