Fossil fuels, similarly -- we are trying to target fossil fuels and design so that you get fossil -- biomass to replace fossil fuel, but biomass based on, for example, woody materials, based on agricultural waste like wheat straw, corn cobs -- agricultural waste, lumber waste residues -- that's very inexpensive feedstock.

WHITEHOUSE: Press Briefing

It's signed contracts with Idaho farmers to buy hundreds of thousands of tons of wheat and barley straw, and hopes to break ground on the first plant, possibly in Idaho, next year.

NPR: Canadian Dreams of Ethanol Distilled from Grass

The huts, made of chalk and straw daub and wheat-thatched roofing, have been based on archaeological remains found at Durrington Walls, near Stonehenge.

BBC: Old Sarum project sees Neolithic huts built