. The L5 Development Group is a privately funded, for profit, commercial space exploration and development program. The L5 Development Group - Solutions in Space Solar Power  

Solar Power


This document and its contents are Copyright © 1986-2017 by FKE and The L5 Development Group. All rights reserved. This Web page, and/or the document it embodies, may not be reproduced, copied, or stored, in part or in whole, in any form or manner (printed, electronic, xerographic, optical, or through use of any other technology), other than for immediate viewing via its original URI at L5DGbeta.com, without the express written permission of the publisher.


Building solar power satellites has been selected as the major target for the initial development work for two reasons: First, a very real and current need for such a system can be demonstrated. Secondly, building and operating solar power satellites can easily be shown to be a profitable enterprise, which will be necessary to attract the investment capital needed to execute this plan as a civilian business operation.

An energy crisis

Modern civilization is extremely dependent on an abundant supply of readily and reliably available electricity. We take it for granted every time we turn on a light, open the door of a refrigerator, or even when buying cans of food at the grocery store which were sealed by electrically operated machinery. Our use of electricity is so pervasive that most of us would be hard pressed to find something we do that does not depend on it without careful thought.

With the increased load of larger numbers of air conditioners in use, recent summers have strained the capacity of the generating facilities in place in many regions. This has resulted in "rolling" brownouts or blackouts - temporary cutbacks and shutdowns of electric service planned by the utility companies to prevent massive failures of the system. Already the generating capacity of the power grid is critically limited. In their complaints about construction of new facilities, such as nuclear power plants, protesters often forget that the existing power plants are getting old and will need to be replaced in the relatively near future. If we wait until those plants have failed before construction of new ones is started, it will already be too late.

Where it once held the potential to be a clean, effective and inexpensive source of energy, atomic power has fallen to disgrace. The price of building nuclear plants has been driven so high that their profit potential has been practically eliminated, even though the real costs of operating nuclear plants are much lower than nearly any other energy source available. In spite of the fact that the nuclear industry has a near-perfect safety record (in the United States, at least), it is perceived by the general public as a menace to humanity. Part of this problem is the fault of the industry itself, which does not want to dispose of its waste in a truly permanent way: All of the disposal plans that have been proposed offer an option of future access to the waste, presumably for recycling when better methods are available. Because of the costs and dangers - real and perceived - of building and operating nuclear power plants, depending on new sources of atomic energy to supply our electric needs is a chancy proposition at best.

Most of the electricity we use today is being generated by facilities that are powered by burning fossil fuels - coal, oil, and gas. Based on technologies that have been used for hundreds of generations, fossil-fueled power plants are well understood, and are readily accepted by the general population. Because they are so well understood, it is easy to forget that hundreds of lives are lost every year in the process of supplying fuel to power these plants. Since smoke and fire are also common-place events in everyday life, it is easy to forget as well that these plants are dumping millions of tons of garbage into the air in the process of supplying us with electricity. The fact that the generator providing the power is miles away when we flip on a light does not lead to an easy association between being able to see in the dark and air pollution, but it is definitely there: Our electric lives are making a significant contribution to the greenhouse effect that appears to be warming the global climate, with potentially disastrous effects.

In addition to their pollution problems, we must also consider the limited supplies of fossil fuels that are available when planning new energy sources. The American economy is largely dependent on foreign oil, much of which is used to supply electric generating facilities. Large reserves of coal and gas have been found within the nation's borders, but even those supplies are limited, with a projected supply of perhaps one hundred fifty years at the current consumption rates. Even if no growth in capacity is taken into account, it would be an extremely short-sighted plan that does not include development of new energy sources beyond that time.

The supply of fossil fuels will probably be extended through increased use of renewable fuel supplies such as fast-growing trees and corn, but the energy available from these sources is also limited and would require a tremendous advance in biotechnology to feasibly supply a substantial amount of the electricity needed by our civilization. Besides which, burning renewable fuels still has the same problems of pollution associated with burning the fossil fuels.

There are electric sources available that don't pollute the atmosphere: hydroelectric power, wind power, geothermal energy, or ground-based solar power systems. Each of these possible sources has a unique set of advantages. On the other hand, each also has one or more siginificant disadvantages that must be taken into account when considering its use as a wide-spread replacement for the existing power supply system.

Hydroelectric plants, for example, tap the power of flowing rivers to convert their energy to something more readily usable. However, most hydroelectric plants require large dams to be built, and huge areas of land to be flooded in an artificial lake to supply the water to power the turbines. This has the potential of displacing communities or damaging fragile ecosystems, both of which reduce the luster of the idea. The number of suitable hydroelectric power sites is also limited, restricting its potential for future growth.

Another non-polluting source of electricity that has been investigated, and exploited to a limited degree, is wind-powered generation. Huge impellers, hundreds of feet across, capture the wind's energy and transfer it to the shaft of a generator through a gear system. Because of their mammoth size, the dynamic loads imposed by the wind, centrifugal force, and a constantly changing gravitational vector present incredible structural stresses on the blades of large-scale wind turbines. If a fatigue failure caused one of the blades of these generators to come loose near its base, it could become a kinetic missile with a terrible potential for damage. A continuous breeze is needed to make effective use of wind power, which contributes to the fact there are a limited number of feasible sites to build these plants. Since the electric distribution grid must be operated with an extremely stable frequency for its alternating current to prevent internal losses, the variable speed of the wind flowing past the turbines' blades must be compensated for at each generator site. Although this is not an impossible task, the increased complexity of the system significantly reduces its reliability and increases maintenance costs. On the surface, wind power may look like an ideal non-polluting source of energy, but it has a number of problems that limit its future utility.

Along similar lines, geothermal energy is being explored as an alternative to traditional sources of power. Besides the expense of drilling wells to tap the heat of the Earth's core directly, there are, once again, a limited number of sites where geothermal energy could be readily tapped. Proposals have also been put forth to use energy stored in the oceans' tides, temperature differentials, and currents. Like geothermal energy, these plans are limited by the number of potential sites available, the large expense of the technological development that would be required to effectively harness the oceans' energy, and the costs of building and maintaining the power plants.

Since the sun shines freely nearly everywhere on the Earth at least once a day, solar power is one of the most popular "alternative" energy sources being evaluated today. Utilization of the sun's energy is already found in many different forms, ranging, for example, from solar heaters for swimming pools, to arrays of solar cells supplying electricity for remote telephone relay stations. There are significant problems with ground-based collection of solar energy which prevent it from becoming a feasible solution to the energy crisis: For one thing, construction of solar collectors large enough to supply the electric needs of our civilization would consume too much land to justify it. In addition, solar energy is only available during daylight hours, and is reduced by cloud cover and seasonal changes of the sun's apparent elevation above the horizon. Although it may be possible to build a single family home, in a rural or suburban area, totally powered by the sunlight it receives, powering a high-rise apartment complex or a large manufacturing facility in a like manner just cannot be done. If solar power is to achieve its promise of supplying clean, inexpensive and abundant energy to our world in an effective and easy to use manner, we will have to go into orbit to collect it.

A combination of the alternative technologies available has the potential to reduce our dependence on large, centralized power plants, leading to a more robust economy, tolerant to a greater degree of failures in the system. Conservation plans can also help cut back the demand for electric power in traditional uses. However, even if all of the alternate power sources were installed, the industrial needs of electric capacity cannot be met without large generating plants. The projected demand for electric power far exceeds the growth potential of our current choices, especially as older plants must be retired from service, and within an relatively short period of time. As a result, additional large-scale generation facilities are still needed, and their construction must be started in the immediate future, or we will be facing an increasingly dire shortage of electricity even as our needs are expanding.

solar power satellite in geostationary orbit (SSI, http://www.ssi.org/assets/images/slide02.jpg)
A Solar Power Satellite in Geostationary Orbit
Image Courtesy of SSI

A profitable business opportunity

In order to meet the energy needs of a growing civilization, FKE is planning to build, and deliver to service, solar power plants in Earth orbit. Manufactured from Lunar materials at a work site far removed from the gravitational wells of planetary masses, these huge structures will be installed at stationary points above receivers tied into the power distribution grid on Earth. Beaming electricity through microwave or ultraviolet laser transmission systems to the power-hungry civilization sprawling across the entire planet, these facilities will finally make commercially viable solar power a reality: With no fuel expense, and with negligible operating costs, we will be able to sell solar-generated electricity at a far lower price than any other means available today, and still maintain a substantial profit margin. Relieved of the pollution caused by fossil-fueled power plants, and of the dangers of nuclear-powered ones, future civilizations will enjoy a cleaner, safer environment than we have today, with the added benefit of economic growth made possible by a virtually unlimited energy source. In the final analysis, this one factor could prove to be the difference between survival of human civilization on Earth and its untimely demise through self-imposed strangulation or suicide. It is this crucial position of solar power satellites that has led us to make them a key component of our space development plan, and a major priority for our research efforts.


 

Valid XHTML 1.0 Strict
Site Features