Solar energy may not be a viable solution for much of Africa. Taking Ghana as an example, solar electricity costs 40 cents to 50 cents a kilowatt hour, while meanwhile Ghanaians pay just 5 cents to 10 cents for electricity from conventional sources. Wind is likewise not a viable option.
That forced Ghana to consider a more imaginative set of choices, among them, sewage. Dumping its payloads into a warm and massive vat that will skim lipids – fat – off the top to provide biodiesel.
But there are more sanitary ways to make a megawatt in Ghana. Kwame Tufor came home from Florida to liquefy Ghana’s coconut husks, cocoa pods, and palm nut shells into gas. But you’d need a lot of coconuts to turn a profit that way. Local farmers could provide their nut shells and cocoa pods for his incinerator.
But he and a business partner are eyeing an old paper farm the size of Brooklyn. Sometime between one 1970s coup and another, the owner ran out of money and political favor, abandoning acres of trees that were meant to be mulched into notepads 35 years ago. Mr. Tufor intends to saw those trees down, replant them, then burn the timber and compress the smoke into a biofuel using dated World War II technology that’s been dusted off by developing world power plants.
At least 10 plants in China now gasify coal this way, while farmers in the Philippines run irrigation pumps on generators that gasify rice husks.