. >> fibrous. >> like a fibrous tumor? >> what's the derivation? >> consisting of -- we don't have that but consisting of or characterized by fibers. [ spelling ] f-i-b-how am i doing so far? >> pretty good. fib. >> r-o-sis. >> no. that would b fibros is. i don't know if that's a word. fibrous. >> we had faith. >> i should have known that. >> it's good. >> we'll give you a clap anyway. >> i'll be here all afternoon, ladies and gentlemen. [ laughter ] >> the spelling bee airs live in saturday on our sister station kb cw 44/cable 12. you can see is streamlines on kpix.com/bee. >> tomorrow we'll be playing that wonderful game are you smarter than a fifth grader? i should have got that. >> it's been fun. >> the r was the hard part. brous. i know that. >> we have spell check. >> and i need write it down. i'll look at it -- if i wrote it down, try that again. >> try on the back of your hand. >> what can you do? >> elizabeth a good speller. >> i feel like i'm getting this reputation and it's not true. i'm glad i'm not playing this game. >> better than me.

narrator: cellulosic material, or biomass, is basically the fibrous, woody, and generally inedible portions of plants. and it is the most plentiful biological material on earth. the challenge for nrel scientists and engineers like andy aden is to design cost-effective conversion plants that can create fuel from many different types of biomass. aden: there are lots of different types of biomass. there are agricultural residues, like corn stover or wheat straw, things that are currently left in the field after the grain has been harvested. there are wood types of feed stocks that are biomass -- wood chips like poplar for example. it's a very fast-growing tree, and you can potentially have plantas of this terial that can produce large amounts of biomass for fuel, all the way even to a prairie grass like switcgrass. the benefits of this material is it's very drought-tolerant and you can get a lot more tonnage of this material off of an acre of land. so there are a lot of reasons and a lot of additional benefits for using biomass as a source of ethanol as opposed to just corn grain, one of which