2006年全球穀物消耗量將會大為增加，而背後原因不是為了人類的吃，而是汽車。美國農業部預測，2006年全球穀物消耗量將增加2000萬噸，其中增加的1400萬噸會用作美國國內汽車所需要的燃料，只剩下600萬噸用來填補逐漸增加中的全球糧食需求。以農業用語來說，全世界需求汽車燃料的胃口是永遠無法滿足的。
投資人總是走在市場最前端，他們已預見生質燃料的高獲利性，因此，世界各地乙醇蒸餾廠和生質柴油提煉廠如雨後春筍般設立。美國玉米用作乙醇原料的消耗量在過去5年已成長3倍，從2001年的1,800萬公噸成長2006年的5,500萬公噸。
在美國中西部一些盛產玉米的州，玉米供應可說是被乙醇蒸餾廠所壟斷。例如愛荷華州營運中的乙醇蒸餾廠，加上準備設立的，總共有55家。愛荷華州立大學經濟學家威斯納（Bob Wisner）指出，一旦這些蒸餾廠全數運轉，將消耗愛荷華州全部的玉米產量。
像麥、玉米、稻米、大豆、甘蔗作物，幾乎我們所吃的都可作為生質燃料的原料，因此，食品經濟和能源經濟的界限漸趨模糊。過去只有食品加工業和家畜業會，購買這些農作物，再加工製造為各項產品賣給超市；如今，生質燃料業者也開始購買穀物，供給乙醇蒸餾廠和生質柴油提煉廠用為原料。
當農作物的食用價值低於燃料價值，市場機制自然向利潤靠攏。
巴西、美國和西歐是當前生質燃料生產重鎮，美國和巴西2005年各生產了400萬加侖（160億公升)燃料乙醇。2006年，美國有5500萬公噸的玉米用來生產乙醇，消耗掉的玉米是全美產量的六分之一，但是卻只滿足了3%的汽車燃料需求。
世界最大的糖生產和輸出國巴西也在改變，巴西國內半數製糖作物收成已轉為製造乙醇的原料。當初不過把10%的製糖作物收成轉作乙醇，糖價就攀升了兩倍。未來，低價糖時代恐將一去不返。
燃料業對穀物貪得無厭的胃口，使穀價上升無可避免，問題是何時上漲？幅度為何？實際上，麥價和玉米價在過去數月已上漲五分之一，這對全世界最貧窮的20億人民而言，他們的糧食開銷佔了所得一半以上，穀價上漲對他們而言實是性命交關的問題。
此外，對於必須進口穀物的低收入國家，例如印尼、埃及、奈及利亞和墨西哥，糧食價格上升可能增加貧窮人口並導致政治動盪，繼而影響全球經濟。
如果乙醇蒸餾工業對穀物需求持續這般爆炸性增長，導致穀價過度攀升，將可預見一場汽車燃料與低收入消費者爭食的衝突，美國政府恐怕必須介入處理。
(本文僅節譯部分內容，全文詳見 http://ens-newswire.com/ens/jul2006/2006-07-15-insbro.asp)
Cars, not people, will claim most of the increase in world grain consumption this year. The U.S. Department of Agriculture projects that world grain use will grow by 20 million tons in 2006. Of this, 14 million tons will be used to produce fuel for cars in the United States, leaving only six million tons to satisfy the world’s growing food needs. In agricultural terms, the world appetite for automotive fuel is insatiable.
Investors are jumping on the highly profitable biofuel bandwagon so fast that hardly a day goes by without another ethanol distillery or biodiesel refinery being announced somewhere in the world. The amount of corn used in U.S. ethanol distilleries has tripled in five years, jumping from 18 million tons in 2001 to an estimated 55 million tons from the 2006 crop.
In some U.S. Corn Belt states, ethanol distilleries are taking over the corn supply. In Iowa, a staggering 55 ethanol plants are operating or have been proposed. Iowa State University economist Bob Wisner observes that if all these plants are built, they would use virtually all the corn grown in Iowa.
Since almost everything we eat can be converted into fuel for automobiles, including wheat, corn, rice, soybeans, and sugarcane, the line between the food and energy economies is disappearing.
Historically, food processors and livestock producers that converted these farm commodities into products for supermarket shelves were the only buyers. Now there is another group, those buying for the ethanol distilleries and biodiesel refineries that supply service stations.
Whenever the food value of a commodity drops below its fuel value, the market will convert it into fuel.
Crop-based fuel production is now concentrated in Brazil, the United States, and Western Europe. The United States and Brazil each produced over four billion gallons (16 billion liters) of ethanol in 2005.
The 55 million tons of U.S. corn going into ethanol this year represent nearly one sixth of the country's grain harvest but will supply only 3 percent of its automotive fuel.
Brazil, the world's largest sugar producer and exporter, is now converting half of its sugar harvest into fuel ethanol. With just 10 percent of the world's sugar harvest going into ethanol, the price of sugar has doubled. Cheap sugar may now be history.
Given the insatiable appetite of cars for fuel, higher grain prices appear inevitable. The only question is when food prices will rise and by how much. Indeed, in recent months, wheat and corn prices have risen by one fifth. For the two billion poorest people in the world, many of whom spend half or more of their income on food, rising grain prices can quickly become life threatening.
The broader risk is that rising food prices could spread hunger and generate political instability in low-income countries that import grain, such as Indonesia, Egypt, Nigeria, and Mexico. This instability could in turn disrupt global economic progress.
If ethanol distillery demand for grain continues its explosive growth, driving grain prices to dangerous highs, the U.S. government may have to intervene in the unfolding global conflict over food between affluent motorists and low-income consumers.
