Crude oil is used worldwide as feedstock for fuel for transportation systems (private, commercial and government, including military and security forces) and as feedstock for manufacturing medicines, plastics, fibers, rubber, home heating oil and other necessary materials. Present world usage of crude oil is increasing each year and is approaching the maximum amount producible from the world's oil fields.

At present, we seem to be discovering new oil fields at a rate approximately one-fourth of the present usage, and the new fields are more expensive to find and to use, thus making the new oil more expensive. We are very near the time when maximum production equals normal demand, and the maximum production is declining each year. Either we find another source such as oil shale or liquefied coal soon, or we will face some form of rationing.

We are using some ethanol and vegetable oils to replace some petroleum-based fuels. This can help some, but in a few years we will need several million barrels per day to make up the difference between demand and supply from crude oil. The demand for food is also increasing, and must be considered.

More energy is required to produce ethanol than is recovered from burning it. This energy must be generated from coal-fired or nuclear power plants.

We sometimes see solar, wind or biomass proposed as substitutes for fuels derived from crude oil, or for feedstocks for medicine, plastics, etc. This only confuses the subject and diverts resources from more productive uses. Both kinds of research and development must be carried on at the same time. Solar and wind power can contribute only a small percentage of present needs.

We are left with the liquefying and gasifying of coal, and with recovery of hydrocarbons from oil shale, tar sands and oil sands as the only ways of providing sufficient fuel and feed stock material to satisfy future demand.

The time when we must have these new fuel sources is very near, perhaps two to 10 years from now.

The important question is, "What do we have in place now, today, to satisfy these needs?" The answer seems to be nothing.

Edward W. Wiederhold of Milford, a 1949 Ohio State graduate in chemical engineering, was a research engineer at the U.S. Atomic Energy Commission at Los Alamos, N.M., in the 1950s, and also served as a senior research chemist and a research and development consultant before retiring in 1980.

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