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Presents a theoretical model for developing environmental conceptions that incorporate environmental knowledge, attitudes/values, and behavioral orientations. Encourages students to become aware of, challenge inconsistencies in, and make informed decisions regarding their commitment to their own or alternative environmental conceptions. Presents examples of strategies that may be adapted for use within this model. Contains 52 references. (JRH)

Outlines constraints facing teacher educators of environmental education. In light of these constraints, it is argued that the provision of separate environmental education curriculum units in teacher education courses is a better alternative then attempting to infuse the approach across a number of discipline areas. (LZ)

Examined different ways in which 10 company executives understand and apply environmental responsibility in their managerial roles. Four conceptions of environmental responsibility emerged from the data: an internal proactive undertaking by the company; a reactive response to external community pressures; a negotiated responsibility based on balance and compromise; and a collective responsibility involving cooperation among companies, government, and community. (Author/MDH)

Examines the relationship between informal environmental interpretive experiences and formal environmental education. Similarities and differences are delineated and implications are drawn for the use of interpretive experiences in environmental education school curricula. The Informal Environmental Learning Checklist (IEL) is presented as a means of enabling teachers and interpreters to evaluate and alter informal learning experiences to meet student needs. (Author/PVD)

In 1989, Boeing announced the fabrication of a tandem gallium concentrator solar cell with an energy conversion efficiency of 30 percent. This research breakthrough has now led to panels which are significantly smaller, lighter, more radiation resistant, and potentially less expensive than the traditional silicon flat plate electric power supply. The new Boeing tandem concentrator (BTC) module uses an array of lightweight silicone Fresnel lenses mounted on the front side of a light weight aluminum honeycomb structure to focus sunlight onto small area solar cells mounted on a thin back plane. This module design is shown schematically. The tandem solar cell in this new module consists of a gallium arsenide light sensitive cell with a 24 percent energy conversion efficiency stacked on top of a gallium antimonide infrared sensitive cell with a conversion efficiency of 6 percent. This gives a total efficiency 30 percent for the cell-stack. The lens optical efficiency is typically 85 percent. Discounting for efficiency losses associated with lens packing, cell wiring, and cell operating temperature still allows for a module efficiency of 22 percent which leads to a module power density of 300 Watts/sq. m. This performance provides more than twice the power density available from a single crystal silicon flat plate module and at least four times the power density available from amorphous silicon modules. The fact that the lenses are only 0.010 ft. thick and the aluminum foil back plane is only 0.003 ft. thick leads to a very lightweight module. Although the cells are an easy to handle thickness of 0.020 ft., the fact that they are small, occupying one-twenty-fifth of the module area, means that they add little to the module weight. After summing all the module weights and given the high module power, we find that we are able to fabricate BTC modules with specific power of 100 watts/kg.