“For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.”

Richard Feynman


ENERGY AND POPULATION: Transitional Issues and Eventual Limits

by Paul J. Werbos (1993?)


This is the ninth in a series of NPG FORUM papers exploring the idea of optimum population-what would be a desirable population size for the United States? Without any consensus even as to whether the population should be larger or smaller, the country presently creates its demographic future by inadvertence as it makes decisions on other issues that influence population change.

The approach we have adopted is the “foresight”process. We have asked specialists in various fields to examine the connection between alternative population futures and the national or social objectives in their fields of interest. In this issue of the FORUM, Dr. Werbos examines U.S. energy requirements and the U.S. population size that would be compatible with a plentiful supply of environmentally benign energy.

The question does not lend itself to formal proof. There are too many variables and value judgements. Yet it must be addressed.

Dr. Werbos is a Program Director at the National Science Foundation. He was with the Energy Information Administration (EIA) of the U.S. Department of Energy (DOE) For a decade. He served on the interagency Task Force on Models and Data convened to respond to the problems identified in the Global 2000 Report to the President.

This paper was drafted before the Iraqi invasion of Kuwait. Some of the developments presented as contingencies have now become realities. Any person interested in understanding the long term implications of that invasion and the subsequent rise in oil prices would do well to read this essay.

-Lindsey Grant, Editor


The editors of this series have asked me to address what appears to be a straightforward set of questions: what U.S. population size is compatible with the environmental consequences of energy use? What levels of population would lead to maximum efficiency in the energy sector, as a guesstimate, in long-term equilibrium?

Many energy analysts tend to ignore the population question, or to treat population as a minor background variable in forecasting twenty years into the future. A few analysts, following the first report to the Club of Rome, decry all forms of economic and population growth. Both sides-the pessimists and the defenders of the status quo-have built elaborate models and theories to defend their viewpoints, often based on questionable hidden assumptions. After years of working through this maze of theories and building a few models myself, I would make the following personal judgements about energy and population

(1) The present mix of fuels and energy technologies is not sustainable in the long-term, even if population were dramatically reduced. In the long term, fossil fuels will run out. Even now, our present ways of using energy have led to unhealthy levels of ozone in almost every American city, to toxic pollution leaking into ground water and into natural bodies of water. In the next decade or two, oil imports may return to being a crisis-level problem, as demand increases and domestic supply decreases, almost inevitably. Sooner or later, we must also deal with the problem of greenhouse warming, which is associated with all realistic uses of fossil fuels.

To meet all the present energy demands, worldwide, plus economic growth, with conventional nuclear power, would imply an accumulating problem with nuclear waste, nuclear proliferation, nuclear material available for terrorists, and nuclear safety orders of magnitude larger than what we face today.

(2) Once a complete transition to sustainable technologies is achieved, we could probably sustain a wide range of possible populations at a reasonable level of efficiency. From an efficiency viewpoint, populations between SO to 100% of the present population would probably be ideal, though environmental quality would probably be better at the lower end of the range. Populations as low as 25 million or so would probably be a problem, because it would be difficult to sustain a complex mix of technologies (even soft technologies) on such a small engineering base; however, we probably could not sustain a population much greater than that if we insisted on using only less expensive, less risky soft technologies. With a high degree of optimism about the soft technologies, and allowances for peak load electricity supplied by solar power, one might hope to sustain a population as large as 60 million or so. For larger populations, we would probably have to rely mostly on direct solar technologies, including a certain mix of technologies as yet unproven. Populations much larger than the present would begin to present problems, because solar energy would become more expensive (due to higher land prices) and also because the concentration of water pollution tends to increase in proportion to population. If our income per capita were as low as that of China, we could support a similar population, but in an economy as rich as ours the population and land supply problems would become difficult.

(3) Regardless of long-term sustainability, the growth of population and the composition of this growth in the next two to three decades is possibly the most serious problem reducing our chance of a successful transition to sustainable technology. At first glance, the connection may not be obvious, but it is really quite strong. Sustainable technologies will take a long time to bring onto the mass market, and the transition will cost billions upon billions of dollars. An important part of the cost will involve research and development which is highly profitable in the long-term; even so, finding the money in the next five years will clearly be a problem- and the next twenty years may not be radically different from the next five.

In these circumstances, the nation will be well advised to do whatever it can to slow the present rate of population growth and the increased energy demand posed by a larger population. Perhaps more important, it needs to change its investment habits to accumulate the capital to make the transition away from petroleum. The biggest obstacle to finding the money-either in the public or private sector-is the general shortage of capital associated with a low national savings rate and the federal budget deficit. We need a skilled and productive labor force. Neither our immigration policies nor our national social policies are focused on this goal. We admit immigrants based on kinship rather than skills. We face rising teenage pregnancy and continuing differential pregnancy-with the poorest who can least afford to raise them having the most children. We wrestle with the costs and results of these problems, rather than trying to avoid them. The costs are very high, and they divert resources from the challenges ahead. A national policy preparing us to cope with those challenges would probably result in immigration and fertility levels corresponding roughly to the “hard path” described by Leon Bouvier elsewhere in this series, and an immediate slowing of population growth.

Finally, it is not obvious that the United States will be able to make the transition to sustainable technologies in time to prevent severe, debilitating rises in energy prices and environmental problems worldwide. Rising energy prices and shifts in the composition of the labor force can slow down economic growth, making it ever more difficult to make such a huge transition, if we wait too long. The solutions and the problems will both take decades to develop, and no one knows which will happen first. If demographic problems over the next few decades result in too much of a delay here, the consequences for our civilization might well be permanent.


This essay has only touched the surface of some very difficult and complex issues.

The transition to sustainable sources of energy will require a whole series of major transformations in the economy, each costing billions of dollars, each entailing major risks, and requiring serious attention now. Failure to make a timely or benign transition would lead to serious problems for national security, the environment and longerterm economic growth. Successful transitions would require major government investment in accelerated R&D, stronger incentives to the private sector, and trillions of dollars in investments from the private sector; all three of these will be hard to come by in the coming years, if the present deficit environment persists. Any population policy which encourages investment and reduces the growth in the nonproductive population would have an immediate impact on the growth of the federal deficit, and help a great deal in increasing the probability of a successful transition away from oil. In the long term, the energy sector and the environment would probably be healthiest if the U.S. population were somewhere around 50 to 100% of the present level, in my view. If one were very optimistic about biomass and international cooperation, and pessimistic about high-tech renewables, then the optimum would be more like 60 million people.

If the issue of population growth is neglected, then, as the essay by Bouvier has shown, it may be difficult to avoid a doubling or even tripling of U.S. population, which would clearly pose problems for energy and the environment, due to higher land costs and water pollution.

This article is excerpted from an 8 page NPG Forum piece. Full copies are available for $1.00 from Negative Population Growth, Inc., P.O. Box 1206, Teaneck, N.J. 07666-1206. Reprinted with permission of the author and NPG.

Chronic Shortages of Water Predicted Even in good years, state won’t have enough

By Elliot Diringer Chronicle Staff Writer

San Francisco Chronicle December2. 1993.


The Wilson administration projected yesterday that drought or no drought, California faces chronic water shortages in coming decades if it does not move quickly to curb demand and boost water supply.

The state’s top water officials said that by 2020, the dams and aqueducts that make up the world’s most elaborate watermoving network will fall short of California’s needs by as much as 4.2 million acre-feet in a good year and nearly twice that in a drought.

Even if all ameliorative measures deemed feasible today are carried out, they said, rising demand will still exceed supply in most years by up to 3.5 million acre-feet, the amount it takes to irrigate a million acres of crops or sustain a city of 800,000.

In laying out their projection, Wilson aides walked a thin a line between sounding the alarm and sounding confident that crippling water shortages can be averted, despite the political stalement that has paralyzed state water policy for decades.

“The history of the water wars is replete with failed attempts …and the problem is only becoming more complex,” said Resources Secretary Douglas Wheeler. “There is a shortfall on the horizon…There are ways to address the shortfall, but we have to act now to adopt those strategies.”

The Department of Water Resources’ gloomy forecast is the bottom line in a 750-page analysis of water supply and water demand during the next three decades. By 2020, total demand could approach 69.4 million acre-feet of water a year, up from 63.7 million acre-feet in 1990. The draft report, the latest in a series of updates to a landmark 1957 State Water Plan, is the first exhaustive look at California’s water prognosis since before the drought.

It shows supply rising slightly and demand going up much faster, driven both by the state’s soaring population growth-from 30 million in 1990 to 49 million in 2020-and continued pressure to allocate more water to restoring rivers, wetlands and wildlife.

Reflecting the tremendous uncertainty and disagreement over how much more water the environment needs, or will get, the report offers not a firm estimate but a range-from 1 million acre-feet to 3 million acre-feet a year. The anticipated shortage for cities and farms would rise or fall depending on what the number turns out to be.

The outlook may become clearer two weeks from now when the U.S. Environmental Protection Agency plans to propose a sweeping set of standards that would divert some freshwater flows from urban and farm use toward protection of the San Francisco Bay and the Sacramento San Joaquin River Delta.

State officials, who have steadfastly challenged the EPA’s authority to step into the long-standing bay-delta debate, said recent meetings with federal officials have produced an encouraging dialogue but no breakthroughs.

State’s Analysis

The supply-and-demand analysis offers a far more sobering picture than the original 1957 plan, which was essentially an engineer’s wish list for dams in every corner of the state, and the five earlier updates, which only hinted at a time when the supply would run out.

Since the last report in 1987, the state has endured its worst drought this century. Environmental interests have gained increasing power over water allocations, and the focus has turned more and more from building new supply to redistributing what already exists.

Reflecting those new realities, the latest report is the first to attempt to estimate environmental needs and the first to suggest that part of the solution is taking agricultural fields out of production, starting with lands in the western San Joaquin Valley that produce selenium-laden runoff.

1993 San Francisco Chronicle. Reprinted by permission.