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Petr Jakes, Ph.D., Department of Geosciences
In preliminary experiments with superheated silicate melts, researchers have (a) noted substantial changes of silicate melt structures with temperatures exceeding the liquids by 350 degrees, (b) recorded experimental evidence and natural evidence for the coupled effect of vaporization and reduction at superheat temperatures, (c) recorded non linear changes in transport properties of melts at temperatures well above the liquids. The observed phenomena (a) and (b) may be used in the utilization of rocks from lunar surface to coproduce the oxygen and metal. Superheating the lunar regolith of suitable composition (e.g., ilmenite enriched lunar regolith) may coproduce the metallic iron, oxygen gas and molten siliceous material suitable for casting of bricks or building blocks. Because of the availability of sufficient energy resources (solar) at the lunar surface , the superheating could be used to improve the economy (self-sufficiency) of the planned permanent lunar base. The ultimate goal of the planned project is the design of a process in which oxygen, metal, and casting material will be co-produced from indigenous materials at the lunar surface using solar energy.
A search of the scientific literature suggest that the polymerization of silicate melts primarily depends on the chemical composition and is little affected by temperature. ISSO researchers demonstrated that highly siliceous melts, quenched from near-liquids temperatures, differ substantially in Raman spectra from those quenched from above the liquids ( + 350ºC). Changes in Raman peaks correlate with fictive temperatures (T) of glasses and with the cooling history of melt/glasses and indicate changes in the volume proportions of different Si-O environments. High-T structures can be quenched and reveal the very high temperature Raman spectra peaks. These changes, similar to changes in the germanium oxides, are interpreted as depolymerization phenomena. Although the use of the term "depolymerization" may be wrong, researchers use the analogy with the structure of minerals to express the "apparent change" (pyroxene chain silicate structures are more polymerized than olivine structures).
In superheated melts, the apparent formation of less polymerized structures is at the expense of more polymerized structures. The "dislocation" of oxygen and other volatile elements accompanied by the formation of zero valency state silicon (i.e., reduction) are intrinsic features of silicate melts at high temperatures and could be modeled by the reaction of enstatite to form forsterite, silicon, and oxygen: 2MgSiO3 = Mg2SiO4 + Si + 02.
Proposal funds were provided to define a preliminary series of high-temperature (1 atm.), experiments in order to determine the behavior of lunar regolith (ilmenite enriched) at elevated (superheat) temperatures. The results will provide estimates of the feasibility of co-production of oxygen, metal and casting material on lunar surface.
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Elizabeth A. Waltz and Russell G. Thompson, Ph.D., College of Business Administration
Recent studies by David Criswell (1991) and Russell Thompson and David Criswell (1992) suggest an order of magnitude improvement in efficiency and cost benefits for solar electricity, provided by the lunar power (LSP) system relative to conventionally generated electricity. To investigate this potential further, a three-part two-year study is nearing completion which evaluates transitional issues and macroeconomic consequences of the introduction of LSP to the energy basis.
The first study considered the investment and initial demand requirements for LSP. With a fully burdened financing scenario, including funding for the initial R&D, the levelized introductory price for LSP was estimated at $0.031 per kilowatt-hour, which is approximately 55% of average U. S. electricity production costs.
The economic contribution of lower electricity prices for the U. S. and world economy was modeled with Global 2100 (Manne and Richels, 1992). Results for the U. S. in Fig. 1 show differential levels of economic performance, as measured by GDP for cases with and without LSP, and with and without carbon constraints (to mitigate CO2 emissions and potential global warning).
Finally, a linear programming model was developed to analyze the impact of these four energy scenarios on consumers. Energy cost results shown in Fig. 2 assume that consumers maintain today's level of energy benefit and incorporate future energy efficiency improvements.
LSP Transition Scenario
The purpose of this study is to define and evaluate a transition scenario for the
introduction of the Lunar Power System (LSP) into the energy mix in the United States.
This study identifies a transition scenario and evaluates the financial impacts,
electricity pricing, and environmental benefits resulting from this scenario.
A transition scenario is important because various parameters that describe the introduction of the new technology must be defined and estimated. The definition of assumptions about how the LSP will be introduced provides the mechanism to initiate discussion and debate with potential interested parties. These early assumptions about the nature, rate, and issues associated with commercialization of the LSP allow at least preliminary analysis of the financial considerations, market demands and pricing and other information which is important in the assessment of the macroeconomic implications of such an initiative.
Earlier studies by Criswell and Waldron (1990, 1991) and Thompson and Criswell (1992) suggest that a large scale, mature LSP source would provide electricity for about $0.011/kW-H, a favorable price compared to today's average price of $.07l/kW-H. However, a shorter term projection was needed to define a basis for an introductory price for LSP electricity. A 20-year transition scenario to the LSP provided the basis for estimating the electricity price to consumers for LSP supplied energy. Further, the scenario identifies potential changes in the utility power generation mix which will have beneficial environmental effects, by reducing the emissions from conventional power generation facilities.
The key findings of the study include an introductory price for LSP electricity at 55% of the current and intermediate term projected electricity price; a major reduction in the amount of carbon emissions, nuclear waste, and resulting heath effects; and a total savings of $75 billion per year to electricity consumers in the U. S. by the twentieth year of the LSP scenario.
Macroeconomic and Environmental Consequences of LSP
Researchers examined the macroeconomic effects of the introduction of system electricity
into the U.S. and world economy. Evaluations have been made under carbon emission
constrained and unconstrained environments. The primary economic measure reported is the
gross domestic product (GDP). Additional measures of economic performance, consumption,
and investment are provided. Additionally, the reduction in environmental CO2, by
substitution of a non-polluting energy source for fossil fuels, has been evaluated.
An introductory scenario for incorporating LSP into the energy mix in the U.S. was developed in the first part of this study. The earlier study had identified a transition scenario and evaluated the financial impacts, capacity expansion path, electricity pricing, and environmental benefits for LSP in the U.S. economy (Waltz and Thompson, 1992). (Environmental benefits result as the integration of LSP in the utility power generation mix reduces dependence on conventional fossil and nuclear power generation facilities).
LSP pricing conclusions and the LSP electricity capacity schedule from the expansion path are utilized as inputs to modify a five region energy and economy model, Global 2100, developed by A. S. Manne and R. G. Richels. The development of the Global 2100 model resulted from increasing concern of the potential for environmental disaster created by the greenhouse effect. CO2 from fossil fuel combustion is a major contributor to greenhouse gas.) Global 2100 provides an integrated energy-economic model for five geopolitical regions. The focus of the model is on the potential costs of CO2 emission reduction.
Results show the favorable impact of lower cost electricity from LSP on U.S. and world GDP, with and without carbon restrictions. Further, for the US and the world respectively, the discounted value (at 5% to 1990) of the projected economic boost is shown to be $11.6 trillion and $73.8 trillion for the case without carbon restriction and $29.6 trillion and $178.3 trillion for the case with carbon restriction. The significance of this cannot be overstated, since the pricing model for LSP, stated above, includes appropriate returns for the initial and subsequent investment. The model results then are quite encouraging, because "excess returns" to the economy are possible in this particular societal investment. (Normally, the expected value of excess return is zero in efficient markets.)
Finally, this analysis considers direct economic costs and does not attempt to reflect the indirect economic costs of externalities beyond that amount which is provided in the carbon tax mechanism proposed in Manne's model to mitigate global warming. These additional external factors in conventional energy options, if included in the analysis, would further strengthen the results of the LSP option vis-a-vis conventional energy choices. Externalities were not included in this analysis because of the wide range of estimates for societal costs, the lack of an agreeable or analytical method for incorporating these costs, and insufficient current scientific knowledge regarding external impacts.
The Cost of Energy to Consumers
Recent energy policy literature has overlooked the consumer (Goldenberg et al., 1988;
Nordhaus, 1991), yet consumers are the driving force behind an economy. When real costs
for basic needs (such as energy) increase, there is a subsequent reduction in the capacity
of consumers to purchase other goods and services, ceteris paribus. The "Consumer
Energy Model" was developed to support policy analysis and development by providing a
consistent basis for analysis and comparison of the impact on the consumer of different
energy scenarios.
The work of this study focuses upon the use of the model with a specific emerging energy technology; the intent of the model, however, is to illustrate an end-use approach and structure for evaluation of energy policy impactors, not to argue for a specific technology solution. Emphasis is upon the importance of energy technology and a shift in the energy basis away from fossil fuels. Specific technological costs, scientific, and engineering issues involved in new energy technology must continue to be debated in other arenas.
Four energy scenarios were evaluated in this study at l0-year intervals through the year 2100 and include comparison of two energy technology bases-conventional energy technology versus a potentially cost-effective renewable electrical energy source in lunar solar power (LSP). (See Criswell, 1991, for a description.) Both energy bases are examined with and without carbon constraints, which may be mandated to reduce CO2 emissions. This model extends the analysis of the Manne and Richels Global 2100 model, although it is not, at this time, interactive or integrated with Global 2100 (Manne, 1989).
The model defines and develops an average consumer's personal baseline consumption levels for three primary end uses of energy-transportation, comfort, and power/lighting. Three energy types-oil (e.g., gasoline), natural gas, and electricity-may conceivably provide these energy needs. The model defines expected or estimated efficiency improvements and fuel switching scenarios. The objective of the model is to minimize energy costs.
Fuel choice and fuel switching decisions are constrained in the model. The cost of energy for a given energy usage, the normal replacement cycles for energy-consuming vehicles and appliances, and energy delivery system considerations are assumed to be the primary determinants in consumers' fuel choice and fuel-switching decisions. Energy price inputs to the consumer model were provided by the Manne-Richels model of economy-energy interactions (Global 2100, Manne, 1992). Energy end-use levels and efficiencies were developed from a variety of sources, but primarily through documentation from the Energy Information Administration (EIA, 1991, 1993).
Results of the model suggest that a shift in the energy basis to a low cost renewable technology such as lunar solar power (LSP) would reduce the annual real cost to consumers for all energy needs by almost 15% in the unconstrained carbon case, and by over 30% in the carbon emission limited case.
Furthermore, for the case with no carbon constraint, the LSP energy option maintains real costs for energy essentially constant over the entire forecasting period, versus an increase of approximately 20% for conventional energy. With the carbon constraint, real costs to consumers for conventional energy increase 100% over the forecast period, while energy costs increase 50% if the low cost renewable energy is available.
The model provides further evidence of the important role of development efforts in energy technology, in addition to current efforts for efficiency and conservation, in energy policy. "Real" costs in this context refer to costs which have a rising fuel cost component, but not including a general inflation component.
References
Criswell, David R. and Robert D. Waldron. "International Lunar Base and
Lunar-based Power System To Supply Earth with Electric Power." Proceedings, 42nd
Congress of the International Astronautical Federation. Paper #IAA-91-699. October 5-11,
1991, Montreal.
Criswell, David R. and R. D. Waldron. "Power Collection and Transmission System and
Method." U. S. Patent 5,019,768.
Goldenberg, J., T. B. Johansson, A. K. N. Redy, and R. H. Williams. Energy for a
Sustainable World. N.Y.: John Wiley & Sons, 1988.
Manne, Alans S. and Richard G. Richels. Buying Greenhouse Insurance: The Economic Costs of
Carbon Dioxide Emission Limits. Cambridge: The MIT Press, 1992.
Nordhaus, William D. "The Cost of Slowing Climate Change: a Survey." The Energy
Journal 12.1 (1991): 37-65
Thompson, Russell G. and David R. Criswell. "Solar Power Productive Efficiency
Potential: A Prototype Analysis." Presented to the EURO XII/TIMS XXXI Joint
International Conference, June 29-July 1, 1992, Helsinki, Finland.
Contents
ISSO -- Institute for Space Systems Operations
1992-1993 Annual Report
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