Energy Use—chapter 10:
Since the discovery of fire, as early as 400,000 years ago, the development of energy technologies has made people’s lives more comfortable. But the flip side of the coin has nearly always been a loss to the environment.
By 1950, world population had passed the three billion mark. By the end of 1999 it reached six billion. Projections for the world population by the year 2050 range from seven billion to 11 billion people. If our approach to using energy does not change, use of the world’s resources will not just keep pace with the growing population—it will occur at an ever-increasing rate as developing countries adopt the energy-rich life-style of industrialized nations.
You have already seen several energy technologies that are alternatives to fossil fuels—from passive solar heating in homes to hydrogen-powered automobiles. Let’s look at two radically new technologies for using energy, and then the social, political, and personal changes needed for long-term survival on Planet Earth.
Energy experts refer to fossil fuels, hydroelectric power, and wind power as “primary sources” of energy. However, that is not strictly true. The energy in these sources comes from the Sun. Like all things in the universe, the Sun obeys the law of conservation of energy. It does not create energy. The Sun converts energy from one form to another, released from the nuclei of hydrogen atoms through a process called nuclear fusion.
Protons in an atom’s nucleus are pushed away from each other, due to their positive electric charge. But another kind of force—the "strong force"—holds the protons together. Strong force acts only at the very short distances inside the nucleus of an atom and is much stronger than the electric force.
The Sun, composed mostly of hydrogen having a nucleus with one proton, is extremely hot at its core—millions of degrees Celsius. [See Temperature Scales.] At that temperature, hydrogen nuclei (protons) collide at very high speeds and nuclear fusion reactions can take place. Through a series of reactions, hydrogen nuclei combine to stable nuclei of helium (each with two protons in the nucleus) and the release of energy.
Scientists have attempted to start a fusion reaction on Earth. The hydrogen bomb was a notable successful attempt. But nuclear explosions are not very helpful in generating energy for everyday human use. For that we need a controlled fusion reaction that changes very small amounts of hydrogen into helium, and produces energy at a continuous rate. Active fusion research projects have been underway in the United States, Europe, and the former Soviet Union since the 1950s.
To achieve fusion the material must be heated to over 100 million degrees Celsius. At that temperature, material becomes plasma, a gas-like mixture of electrons and protons like the interior of the Sun. The problem is how to contain this hot plasma. If it touches any container, it cools down to temperatures too low for fusion to occur. Since plasma is made from electrically charged particles it can be confined by magnetic forces—a fusion research effort known as magnetic confinement. Another approach is to form the plasma starting from a solid pellet of frozen deuterium, a form of hydrogen, and heating the pellet by firing super-powerful lasers at it. This research is called laser-based inertial confinement fusion and in the USA is done mostly at the National Ignition Facility at Lawrence Livermore National Laboratory. Both methods, magnetic confinement and inertial confinement, require a great deal of energy.
For a history and latest breakthroughs in nuclear fusion research, refer to: http://en.wikipedia.org/wiki/Timeline_of_nuclear_fusion.
See also, feature article in Science (AAAS) by Daniel Clery: The new shape of fusion (2015-05-21). Excerpt: ...plasma is not easy to master. Confining it is like trying to squeeze a balloon with your hands: It likes to bulge out between your fingers. The hotter a plasma gets, the more the magnetically confined gas bulges and wriggles and tries to escape. Much of the past 60 years of fusion research has focused on how to control plasma. ...Near a spherical tokamak's central hole, the Oak Ridge researchers predicted, particles would enjoy unusual stability. Instead of corkscrewing lazily around the tube as in a conventional tokamak, the magnetic field lines wind tightly around the central column, holding particles there for extended periods before they return to the outside surface....
Solar cells, also called photovoltaic cells, were developed for the space program as a way of converting sunlight directly into electrical energy. In a solar cell, light is absorbed by a material called a semiconductor, usually silicon with special impurities in it. When sunlight falls on this material the light energy is turned into electrical energy. Almost all spacecraft, except those destined for the outer reaches of the solar system, are equipped with solar cells for electricity.
When solar cells are generating electricity, there is no pollution. There is nothing to wear out from moving parts, only aging of the semiconductor material. You have probably seen the solar cells that power calculators or watches. They also supply electricity in locations remote from utility company power lines for things such as ocean buoys, rural homes, and highway call boxes.
The solar cell on a calculator is about the size of a postage stamp. To supply all the needs of a typical U.S. household could require a 20 foot by 20 foot array of cells that would easily fit on top of the home. The size of an array needed for a multi-story apartment building could be too large for the roof, so would require additional creative design.
The cost of electricity from solar cells has been falling as newer cells are more efficient and economies of scale make the per unit cost less. There will surely come a time when electricity from solar cells easily compete with other sources, especially if government subsidies for fossil fuel systems were to be re-assigned to alternative energy systems. In remote locations without access to power lines, solar electricity is already a cost-effective choice.
As with all forms of solar power, the electrical energy must be stored for use when the Sun is not shining. For such storage, a number of options are being explored, many relying on connection with existing electrical grids. Solar cells can store energy by charging rechargeable batteries, powering electrolysis to produce hydrogen fuel from water, or pumping water from lower to higher elevation for releasing energy at times when there is little or no direct sunlight.
For insights into how solar cells were invented, read the article, The Invention Of The Solar Cell, http://www.popsci.com/article/science/invention-solar-cell, by John Perlin, Popular Science, 2014-04-22.
The two power sources just described both exist because of government research. Fusion power will take more research dollars if it is ever to be viable; and even though solar cells have expanded far beyond the space program, government money has helped (and will probably continue to help) to make solar cells more efficient at lower cost.
Fusion technology and solar cell technology have a difference that highlights one of the choices energy users must make as we move into the future. The choice is one of scale. A fusion power plant might be similar to current electric power plants—a massive cooperative effort among a whole nation of energy users. Once completed, the fusion plant’s power would be available far and wide to everyone on the power grid—a centralized power source. In contrast, small solar cell arrays can be placed right next to the place where the energy is needed, or even built into the device, so that no energy is lost in long-distance transmission—a decentralized power source.
In the realm between science fact and fantasy are ideas that would reverse the roles of fusion and solar cell technology. In 1991, researchers from the University of Utah claimed to have released energy from the fusion of hydrogen atoms in a simple tabletop apparatus. It seemed a dream come true. Energy would become inexpensive and environmentally benign and virtually unlimited. It was on all the front pages. The U.S. Congress scheduled hearings to explore impacts of this breakthrough. Unfortunately, the experiments could not be replicated, and the promise of a small fusion reactor we could install in our garage remains elusive.
Other scientists have proposed using solar cells to create large centralized power plants. One of the boldest ideas is to assemble vast arrays of solar cells in orbit and convert the electricity into microwave beams for transmission to giant receiving stations on Earth.
Recent history contains several examples of revolutions in the way humans use energy. The development of the steam engine around 200 years ago ushered in the age of fossil fuels. The distribution of electricity 100 years ago abruptly changed our energy habits, as did the rise of the automobile shortly afterwards. Less than half a century ago nuclear power entered the field as an entirely new source of energy.
Many people believe we are poised at the brink of another revolution. Articles in newspapers and magazines keep popping up about some technology or other—alternative fuels, superconductors, new fuel cells, cold fusion, hot fusion—some breakthrough that will be our energy salvation. It seems something big ought to be happening, but it just isn’t.
Our automobile-centered culture has resulted in sprawling, very inefficient cities. People's commute times have increased and degraded their quality of life. Is it possible for us to embark on a path of redesigning cities that are intrinsically more efficient? Can we have cities where systems of business, goods, services, and entertainment are designed so people do not need cars as much?
Maybe the biggest thing that is happening is a growing awareness. We see the impact of energy use on the health of humans who breathe city smog. We measure the increased acid content of rainfall—acid that comes from compounds billowing from our electric power plants and motor vehicles. We are getting a clearer picture of the entire global system. As our use of energy puts more and more carbon dioxide into the air, scientists work to predict its effects on the global climate. And as reserves of fossil fuels get lower, they will become more expensive. Whether there is a big breakthrough or not, something needs to change.
Improving energy efficiency, developing alternative fuels, improving and using public transportation, installing thermal insulation, recycling materials such as aluminum, cutting waste from daily energy-use habits—all these things can be part of a solution. We know they work because we are already doing them. Some of the groundwork is already laid.
The Deep Decarbonization Pathways Project (DDPP) is a project of the Sustainable Development Solutions Network of the United Nations. It is an initiative to understand and show how individual countries can transition to a low-carbon economy and how the world can meet the internationally agreed target of limiting the increase in global mean surface temperature to less than 2 degrees Celsius (°C). Achieving the 2°C limit will require that global net emissions of greenhouse gases (GHG) approach zero by the second half of the century. In turn, this will require a profound transformation of energy systems by mid-century through steep declines in carbon intensity in all sectors of the economy, a transition we call “deep decarbonization.”
What happens now depends on the next generation of leaders from the industrialized nations. It depends on you.
Remember Mary Ann Piette, she is one of many scientists and engineers who specialize in the use of energy. She recently conducted a study of how to improve energy efficiency at 28 public buildings. One of them was Edgerton Elementary School in Kalispell, Montana, where, as part of the study, the following improvements were made. Roof insulation was increased from R-11 to R-38. Wall insulation was increased from R-11 to R-19. Single pane windows with an R-1 rating were replaced by double paned windows with an R-3 rating. Additionally, the foundation was extended above the floor and earth was piled against it outside to provide further insulation. Energy efficient fluorescent light fixtures were installed. The air conditioning systems were improved. The yearly energy needs for the building were reduced from 114 kilowatt-hours per square foot of building to 14 kilowatt-hours per square foot, saving the school district thousands of dollars in energy costs each year.
The energy use in one school was cut to less than one eighth of what it had been by using a little bit of new technology, a little bit of ancient technology, and a lot of practical sense in the use of insulating materials that are commonly available. If all energy use were reduced that much think of how that would affect air pollution, the number of oil spills, and global climate change.
It worked in Kalispell, Montana. Can it work worldwide and into the future?
The Rise of Information and Communications Technologies
Do you know anyone who would "just die," or "flip out" if deprived of their mobile phone?
Rapid growth of the global digital era in this millennium, information and communication technologies (ICT), is affecting our societal energy use in ways that were not even foreseen before the year 2000. Depending on who you are listening to, the effect is either beneficial or detrimental.
On the detrimental side, Mark Mills, CEO of Digital Power Group, authored a report The Cloud Begins With Coal: Big Data, Big Networks, Big Infrastructure, and Big Power, (PDF,) that concluded the global information-communication-technologies system, sometimes called "the cloud," at that time (August 2013) consumed 1,500 terawatt-hours of electricity annually, nearly 10 percent
of the whole world’s electricity generation, equal to
the combined electrical generation of Japan and Germany, or as much electricity as global lighting did around 1985. Hourly Internet traffic may exceed the Internet’s annual traffic in the year 2000. This problem is also summarized in "Bracing for the Cloud—Digital Economy Requires Massive Amount of Electricity" (at the
Breakthrough Institute website).
Mills' analyses have been challenged as seriously flowed. Jonathan Koomey, Research Fellow at the Steyer-Taylor Center for Energy Policy and Finance, Stanford University, who states that Mills' analyses give results that are high by at least an order of magnitude (10x). See http://thinkprogress.org/climate/2013/08/25/2518361/iphone-electricity-refrigerator/ for details. Also http://thebreakthrough.org/index.php/programs/energy-and-climate/no-more-railing-against-iphones/
On the beneficial side is the argument that ICT actually helps reduce energy. High-speed internet and mobile technology have made possible remote meetings, telecommuting, and even tele-medicine,
all of which reduce energy-intensive auto and air travel. Email and mobile devices have significantly cut the use of paper in our society, which is a very energy intensive industry. Delivery of physical newspapers, journals, and magazines involves harvesting trees, converting them to pulp, forming them into paper, running equipment to print the content on the paper, and then after all that, putting the paper on airplanes and trucks burning fossil fuels for delivery. Electronic newspapers, journals, and magazines are so much less costly to produce and deliver, energy-wise and resource-wise, it's no wonder that most successful newspapers are deeply committed to electronic distribution.
Nonetheless, even if the cloud consumes only one tenth of what Mills claims, that sort of development in societal energy use is not negligible by any means. Proliferation of mobile devices, smartphones, as well as business internet dependence is steadily increasing demand for access to information and communication through the cloud. Finding technologies that minimize the energy needed for operation of the cloud is clearly important.
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