Jeff Green | Mar 16, 2006
March 16, 2006
Back toHomeMarch 16, 2006
Global Change Part 3:Getting off oil
Commentary by GrayMerriam
There is no question that our fossil fuel-based, automobile-centred, throwaway ‘civilization’ is going to change. What will be some of those changes?
Our food production is heavily dependent on fossil fuels. That has to change. It already is changing in some places. U.S. agriculture has reduced its gasoline and diesel use by 40% since 1973. A large part of that gain was due to farmers giving up age-old addiction to the mould-board plow and, instead, adopting new low- and no-till methods. Similar gains are being made in Canada , Brazil and Argentina . Unfortunately, farmers in developing countries at the same time were changing from draught animals to tractors, increasing food's dependence on oil.
Heavy use of fertilizers also makes food depend on fossil fuels. World over, it takes about a ton of fertilizer to produce 13 tons of grain. That fertilizer accounts for 20% or more of the fossil fuel energy that goes into food production. The energy is needed to make nitrogen fertilizer, to mine and to transport phosphates and potash. Use of fertilizer is being reduced mainly because its cost has made users more thoughtful. Rigorous soil testing can prescribe exact amounts and types of fertilizer for particular crop and soil combinations. Thoughtful crop rotations can reduce use of fertilizer. Using legumes that can take nitrogen from the air and put it into the soil, will feed that nitrogen to subsequent crops. Soybeans can significantly reduce the amount of nitrogen fertilizer that must be supplied to a following corn crop. Matching the amount of manure production of a farm to the cropland area can permit an efficiency that is impossible if manure production and cropland are mismatched. ‘Factory farms’ often have more manure than their land can use and consequently costs go up and efficiency goes down for both fuels and fertilizers.
The relationships between food and fuel will go even deeper. Food and fuel will compete for use of land because food and fuel are fundamentally related by economics. Until the 1970s a barrel of oil was worth about one bushel of wheat. Since then a barrel of crude has risen to be worth about 13 bushels. This has huge effects on international economics. The dependency of the U.S. on imported oil has led to their largest trade deficit ever; exporting grain can no longer cover the cost of importing oil. But the economic linkage between food and fuel is getting even more intricate.
Production of alcohol to be used as fuel requires land to grow the corn or sugar cane used to produce the alcohol. If corn brings more money when used for alcohol production than when used for food, fuel will steal that land from food production. There is no question that this sort of food versus fuel competition for land is happening. World production of fuel alcohol increased twelve fold between 1980 and 2005. Use of land for fuel production is largely economic rather than based on energy conservation. Producing ethanol from U.S. corn averages only 1.5 units of energy for fuel from each one unit of energy used to produce the corn. A lot of corn production is less efficient. But ethanol produced from Brazilian sugar cane can produce up to 8 units of fuel energy for each energy unit used to produce the cane.
Similar food versus fuel competition is arising from production of diesel fuel from oils in crop plants (biodiesel).
The European Union has set a goal of producing 5.75% of all its automotive fuels from biodiesel by 2010. Most of that production will be from acreage devoted to rapeseed (canola). In the U.S. there is a $1 per gallon subsidy being paid for biodiesel production. Consequently, almost half of the Iowa soybean production soon will be used for biodiesel.
It seems clear that affluent drivers will be competing with low-income groups who need food. Not only will fuel compete with food for use of farmland, but increasing price of oil will promote clearing of more land, often marginal, for growing fuel crops and this could have extremely destructive effects on the environments of rural peoples and native species.
Irrigation also is a major energy user in many agricultural areas. As cost rises for the energy used to pump and distribute the water, the costs of irrigation-based agriculture will soar. Those costs will be increased even more because the excessive use of water for irrigation is depleting the sources of that water. For example, the Ogallala reservoirs that stretched from the southern Prairie provinces to the Texas panhandle is ‘fossil’ water. It does not get any recharge from the surface so once it is used up, it is gone. As irrigation has pumped water out of the Ogallala, the water level fell, so wells had to be deepened and more energy had to be used for pumping. Illustrative of our socio-political responses to such problems in the 1960s, the Texas State Legislature authorized a ‘water depletion allowance’ to help out the farmers in the panhandle who needed to pump the water from greater and greater depths. They used the money to deplete the reservoir even more.
As we face ever-increasing energy costs, irrigation will become uneconomical and the world’s agricultural area will shrink.
As we are forced to get off oil, urban dwellers will be affected by more than just food production. Cities are almost totally dependent on distant rural areas for their food supply. Cities require 20 or more times their own area of productive land to supply their food. Currently those areas can be anywhere on the globe at any season. Urbanites also require large areas outside the city for recreation, vacations and other activities. They also are dependent on rural areas for disposal of their wastes. Urban commerce also depends on transportation, increasingly by truck. ‘Delivery just in time’ may need to revert to keeping stock on hand as economic decisions become driven by cost of truck fuel.
As fuel becomes expensive and in short supply, the entire set of processes that make a city function will be restructured. Reuse of already-manufactured items and supplying resources from recycling of non-reusable items will be normal components of the urban economy, not just because of resource shortages but because of shortages of energy to access and transport resources. The commuter lifestyle that is so prominent in North American cities will require restructuring and the new form will necessarily reduce the demands for transportation energy. Alternative forms of transport will be required as well as alternative behaviours of suburbanites, rural commuters and their employers.
We will get off oil and as we do, very few elements of our fossil fuel-based, automotive-centred, throwaway society will be untouched.
For more discussion, see “Plan B 2.0”, 2006, by Lester Brown, from the Earthwatch Institute or go to www.earthpolicy.orgOther Stories this Week View RSS feed