Ze-gen, a company that plans to round up waste from construction sites and turn it into gases that can be used to generate electricity, has won $20 million in funding to help build its first full-size facility.

Based in Boston, Mass., Ze-gen has been moving quickly to prove its process at a small test facility, completed in the second half of last year, and start building a larger, commercial plant.

The gasification process is a bit different from regular burning in that the heating takes place under contained and pressurized conditions. For Ze-gen, that means physically pushing wood scrap into molten metal (also made from scrap material). Aside from causing far less pollution than a normal burn, gasification also produces more desirable byproducts — in this case, hydrogen and carbon monoxide.

Although there are only a handful of companies pursuing trash gasification, a similar process is used on different substances by other companies, like Range Fuels, which plans to use harvested wood and agricultural leavings to create cellulosic ethanol. A number of utilities also hope to use coal gasification technologies to clean up the dirty fuel. In general, gasification is considered attractive because it is a fairly well-proven technology.

Omar Zawawi Establishment, a division of the Omzest Group in from Oman, led the round, with participation from previous investors Flagship Ventures, VantagePoint Venture Partners and the Massachusetts Technology Development Corporation. Ze-gen’s first round of $2.5 million took place almost exactly a year ago.