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This extended abstract describes early-stage research on the research, design, and development of two culturally situated STEM curriculum units for Navajo Nation (Diné) middle school students, on the topics of energy and water, blending immersive and hands-on experiences. The first unit addresses the significant issue of energy access on Navajo Nation, where 32% of homes lack electricity. Culturally relevant, virtual experiences provide engaging and motiving narrative-based contexts for learning, aiming to inspire the next generation of Diné engineers and scientists to use their cultural and STEM knowledge to support their communities. We present the design of a prototype exploring options for solar energy on Navajo Nation, using immersive, place- based virtual representations, and feedback from teachers and students who engaged with the prototype. We describe the design of the full energy unit, and upcoming plans for classroom testing during spring, 2025. Initial findings from this classroom testing will be shared in the poster presentation of this extended abstract at the ILRN conference in June 2025.
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Optimization of solar-driven systems for off-grid water nanofiltration and electrification
Abstract The work described is motivated by an inability to extend central infrastructure for power and water to low-population-density areas of the Navajo Nation and elsewhere. It is estimated that 35% of the Navajo population haul water for household use, frequently from unregulated sources of poor initial quality. The proposed household-scale, solar-driven nanofiltration (NF) system designs are economically optimized to satisfy point-of-use water purification objectives. The systems also provide electrical energy for a degree of nighttime household illumination. Results support rational design of multiple-component purification systems consisting of solar panels, a high-pressure pump, NF membranes, battery storage and an electrical control unit subject to constraints on daily water treatment and excess energy generation. The results presented are conditional (based on initial water quality, membrane characteristics and geography) but can be adapted to satisfy alternative treatment objectives in alternate geographic, etc. settings. The unit costs of water and energy from an optimized system that provides 100 gpd (1 gallon is 3.78 L) and 2 kWh/day of excess electrical energy are estimated at $0.16 per 100 gallons of water treated and $0.26 per kWh of nighttime electrical energy delivered. Methods can be used to inform dispersed infrastructure design subject to alternate constraint sets in similarly remote areas.
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- Award ID(s):
- 1735173
- PAR ID:
- 10195387
- Date Published:
- Journal Name:
- Reviews on Environmental Health
- Volume:
- 35
- Issue:
- 2
- ISSN:
- 0048-7554
- Page Range / eLocation ID:
- 211 to 217
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1515/reveh-2019-0079
