TCS Daily


Renewable Realities

By Sallie Baliunas - April 23, 2002 12:00 AM

"After the last woman has been sawed in half, after the elephant has been made to disappear, after the last brood of chicks has been made to appear in a spectator's pocket, the magicians will sit around for hours in their magical headquarters and talk about the simplest of all effects.
"In the trade it's called the Scarne effect."

-- Introduction to Scarne on Cards by W.A. Caldwell

John Scarne never believed in luck. His fingers deftly dealt cards almost as fast as his mathematical mind computed gaming odds. He was a master card player because he knew card games rely on a mixture of skill and probability, but not luck. During World War II the War Department had Scarne educate our soldiers on gambling scams in the military.

I mention Scarne to make a point as I begin a series focused on whether renewable energy sources can meet future U.S. energy needs. In the realm of energy, as in card games, luck does not exist.

Renewables

Life depends on energy. And energy is not only essential to life, it is essential to civilization. Early hominids first controlled fire some 1.5 million years ago and have traveled a long road in improving their utilization of energy. With energy they improved their chances of survival.

According to estimates by researchers at the UCLA Gerontology Research Group, Homo sapiens' average life expectancy 50,000 years ago was 10 years, owing to death by disease, predators and accidents. The average life expectancy in the United States is now over 76 years, thanks to energy use and science that have curbed nature's brutality. The wealth arising from energy use enables health and welfare to prosper.

Today approximately 85% of our total energy needs are met by fossil fuels, 8% comes from nuclear power and only 7% by renewables. Renewables other than hydroelectric power - geothermal, landfill gas, solar and wind power, plus incineration of wood, municipal waste or other biomass material that can be regrown or re-accumulated - account for only 2% of the 35% of our energy used to produce electricity.

Providing energy growth is essential to economic growth. A bill now in the Senate, S. 517, would focus most of our energy development on renewable energy sources - now redefined to exclude hydroelectric power, because of the apparent detrimental environmental footprint of dams Electric utilities would be mandated to increase to 10% the portion of their electricity provided by renewables - except hydroelectric power - by 2020.

Such a requirement might seem easily accomplished. That's perhaps why Independent Senator from Vermont, James Jeffords aimed to double the renewable requirement, again excluding hydroelectric power, to 20%. That amendment, though, was defeated.

But as for reliably providing for future energy growth by relying on renewables - that's akin to relying on luck. As Scarne would say: There's no such thing as luck in the realm of energy!

The reasons have to do with the laws of energy.

What energy is

We learned in school that energy is defined as the ability to do work, and that the rate at which energy is used is power. We also found out that energy can neither be created nor destroyed, only converted from one form to another.

As the Nobel Physicist and superb teacher Richard Feynman wrote in Six Easy Pieces: " There is a fact, or if you wish, a law, governing all natural phenomena that are known to date. There is no known exception to this law - it is exact so far as we know. The law is called the conservation of energy. It states that there is a certain quantity, which we call energy, that does not change in the manifold changes which nature undergoes. ... It is not a description of a mechanism, ... it is just a strange fact that we can calculate some number and when we finish watching nature go through her tricks and calculate the number again, it is the same."

Some examples of energy are heat energy, electrical energy, electromagnetic energy, chemical energy, nuclear energy, kinetic energy and mass energy.

Feynman highlights that we describe energy as a number. As on a double-entry accounting spreadsheet, if we add energy on one side of the ledger we must subtract it from the other side. And as long as we have properly counted all the different forms to which energy has been converted in the physical process, the bottom line is that the net of input to output is always zero. That's true whatever counting system we use, even if I count in Sumerian. The conservation law stands.

Our knowledge and control of energy continues to progress, so much so that modern Homo sapiens verges on replicating the fusion process that powers the Sun as it converts simple hydrogen into more complex and more massive atoms like helium. Still, we cannot create energy ex nihilo. Because of the law of conservation of energy, we are allowed only to convert energy from one form to another.

And this is where the argument for renewables as a means of growing our energy supply and our economy fails.

Sources and non-sources of energy

If fossil fuels, uranium and hydroelectric continue to be disfavored for providing growth in energy needs, then growth will rely on expanding the remaining renewables. Furthermore, fossil fuels, uranium and hydroelectric energy supplies may be forced to shrink from the base production they now yield, further increasing reliance on renewables.

But the physical laws make the prospect for renewables on a grand scale look dismal: solar and wind energy have enormous environmental footprints. Because they are dilute and intermittent sources, they require great acreage. Their intermittency requires that stable power sources like coal or uranium provide the steady base so critical to electrical supply. Biomass power requires frequent clear cutting of areas devoted to growing fast-rotation woody crops. Large swaths of land devoted to biomass clear cutting, wheezing wind towers or habitat-hungry solar facilities could be viewed as aesthetic, and actual, environmental hazards. Opportunities for power from geothermal sites and landfills are limited, and decline with use.

Hydrogen fuel cells, often touted as another futuristic renewable, merely carry energy. Fuel cells are not sources of energy. The process of energizing a fuel cell with hydrogen cracked from methane (itself a valuable energy resource) or water requires more energy than returned from use of the fuel cell. Their utility is in applications where people may want zero local pollutants like oxides of nitrogen or sulfur. But if carbon dioxide emissions are also undesired, then fuel cells would be disfavored unless the hydrogen-production and distribution phases of charging a fuel cell were to use no fossil fuels, but instead rely on uranium or renewables.

Conservation is sometimes lumped with the neauveaux renewables (i.e., minus hydroelectric power) as a source of energy. Conservation and efficiency improvements may make sense on their own economic or other merits and play an important role in energy policy, but they are not sources of energy.

Securing U.S. energy and electrical production is a high-stakes effort, because our powerhouse economy depends on energy. But energy production depends only on skill - i.e., the laws of physics - and not luck. Solar, wind and biomass energy cannot be counted on to provide the timely, reliable, inexpensive electricity resources the U.S. needs. As Scarne writes, "So much for luck."

Stay tuned for the luckless facts of science in energy and electricity production.
Categories:
|

TCS Daily Archives