Gasifying waste for heat and electricity

A small US company has developed a shipping container-sized device that turns waste into electricity and heat. Rather than burning it, IST Energy 's Green Energy Machine (GEM) gasifies waste products such as food, plastics and agricultural waste.

CNET reports the company's chief executive, Stu Haber, as saying: "Normally, when we tell people what we're doing, they say, 'You can do that? I had no idea that was possible."

IST says that because the system operates under negative pressure, no gases are emitted during gasification, and that the electrical generators used meet emissions standards for NOx, SOx and CO2. "The GEM actually reduces carbon emissions as a result of the reduction in water hauling, landfill and fossil fuel use. The generator does release some carbon emissions, but this is offset by other components of the GEM, which reduce greenhouse has emissions by 540 tons annually, making the whole system carbon negative," the company says.

The company claims the GEM can convert 95 per cent of its waste into usable energy, and says that three tons of trash a day can heat and power a 200,000 square foot building holding 500 people.

The unit costs $850,000, and IST claims the payback time from reduced waste and energy costs will be three to four years, though this will obviously vary depending on the amount of waste the system is fed, and the energy performance of the building.