Monday, July 24, 2006

Will Sweet Potatoes Give You Gas?

Of course, I'm talking about biofuel -- what were you thinking? Anyway, biopact takes note of the planned development of a integrated biogas-ethanol plant in the African South American nation of Guyana that would use sweet potatoes, cassava and rice residue as the feedstock for a number of products, including biomass for electricity generation. The plant requires an investment of $140 million, and would create, in addition to ethanol:
  • 120 million cubic metres of methane (bio-gas) per year because of the inclusion of an anaerobic digester fed by field and processing based biomass residues. This energy source will be used to generate steam to power a generator to produce electricity.
  • 150,000 metric tonnes of organic fertilizer per year
  • 150,000 metric tonnes of carbon dioxide gas (CO2) which will be used in the manufacturing of soft drink beverages
  • excess steam will also be available which will be used for sterilising purposes (such as the sterilisation of containers and fresh agricultural products)
  • several tens of thousands of liters of pure drinking water, from a reverse-osmosis plant driven by the steam, would also be released as a byproduct
  • finally, the biomass plant provides 20,000 metric tonnes of ammonia, that can be converted into bio-fertilizer (namely N-fertilizer, which is normally derived from natural gas).
The blog post that serves as my source is a little sketchy on who's building this, but I'm guessing it's Canada-based Guyanese company Anand Marketing (their president is quoted in the article). I'd imagine some real economic benefits could come from such a development, but two things make me scratch my head just a bit: 1) can countries like Guyana afford to devote cropland and the food it produces to ethanol production, and 2) why does the US need to outsource this production to Africa (the ethanol will be sold in the US market)? I think there are many, many types of sustainable development that could benefit the developing world, but I've got to wonder if this is one of them... Still, if many of these products are used in Guyana, I'd imagine many would find real benefit in them.

Categories: , , , , , ,