An open-source spectral measurement platform for plant reflectance and material identification

▼Western University's Free Appropriate Sustainability Technology (FAST) Research Group

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Spectral sensing plays a crucial role in agriculture, environmental monitoring, and material characterization, providing non-destructive insights into chemical composition and physiological status of plants. Commercial spectrometers, however, are often expensive and lack modularity, which limits their adoption in educational, research and field applications. The developed open-source spectral measurement platform addresses this gap by offering a low-cost, customizable solution for reflectance analysis in plant leaves and diverse materials. The system integrates a Hamamatsu C12880MA miniature spectrometer with dual illumination: a white LED and a 3 mm incandescent bulb, covering 340–850 nm. Control and acquisition are managed by a Teensy 3.2 microcontroller through a Python interface that enables calibration and data storage. The modular enclosure, fabricated via RepRap-class fused filament-based 3D printing and PVC components, ensures flexibility and reproducibility. Validation tests demonstrated accurate wavelength alignment when exposed to laser sources, with peaks detected at 407 nm and 663 nm, and mean squared errors of 0.0131 and 0.0208, respectively. Ambient light comparisons with a commercial OSHP spectrometer yielded an MSE of 0.0105 (~10%), indicating strong agreement. Reflectance measurements using a ColorChecker Classic confirmed consistency in 340–850 nm, validating the suitability of the device for plant reflectance analysis and material identification in both scientific research and educational settings.

▼Pearce publications

FAST · MOST · QAS

Agrivoltaics · Energy Conservation · Energy Policy · Floatovoltaivs · Industrial Symbiosis · Life Cycle Analysis · Materials Science · Medical · Open Source · Photovoltaic Systems · Resilient Food · Solar Cells · Sustainable Development · Sustainability Education · Water

The Western Innovation for Renewable Energy (WIRED) system is currently under construction to test out new open source methods to reduce PV systems costs and enable novel forms of agrivoltaics including the world's first agrivoltaic agrotunnel.

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  The Agrivoltaic Potential of Canada
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  Social acceptance of agrivoltaics in Canada: Insights on public perceptions across technologies and provinces from a nationwide survey
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  Net Zero Agrivoltaic Arrays for Agrotunnel Vertical Growing Systems: Energy Analysis and System Sizing
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  Regenerative Agrivoltaics: Integrating Photovoltaics and Regenerative Agriculture for Sustainable Food and Energy Systems
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  Agrivoltaics as a systems innovation: multi-dimensional benefits from global studies across climate, agriculture, energy, and ecosystems
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  Creating just agrivoltaic transitions for large-scale solar: a comparative multi criteria analysis
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  The potential of agrivoltaic systems to meet energy demand of data centers in the United States
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  Some like it hot, some like it partially shaded: The effect of semi-transparent solar photovoltaic modules on the growth metrics of greenhouse cultivated spicy peppers
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  Integration of semi-transparent photovoltaic modules and heat pumps into agrivoltaic tomato greenhouses: Energy, economic, and environmental savings
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  Strawberry agrivoltaics in Canada: Comparing uniform thin film and non-uniform crystalline silicon semi-transparent solar photovoltaic modules in controlled environment agriculture
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  Climate-Resilient Crop Production Under Agrivoltaics: Experimental Evaluation of Amaranth Production With Semi-Transparent Photovoltaic Modules in Canada Under Changing Climates
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  Is Non-Thermal Plasma Treatment of Commodity Lettuce Seeds Worth It? Economic Impacts and Yield of Lettuce in Indoor Vertical Farming Testing Dry Air, Wet Air, N2 and O2 Plasmas
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  Lighting Energy and Revenue Analysis in an Agrivoltaic Agrotunnel for Lettuce and Swiss Chard Production
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  Full Heads or Cut and Come Again? Economic Analysis of Leafy Green Cultivation in Solar-Powered Indoor Vertical Farms
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  Heat Stress Tolerance in Organic Romaine Lettuce Using Crystalline Silicon and Red, Blue & Green-Colored Thin Film Agrivoltaic Systems
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  Agrivoltaic Lettuce Production Under Future Climates: A Sustainable Strategy for Optimizing Food and Energy Yields
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  Effects of Thin-Film and Wafer-Based Photovoltaic Module Transparency and Spectral Properties on Microclimate and Turnip Yield in Agrivoltaic Systems
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  Photosynthetically active radiation complexities in agrivoltaic policy mandates: Insights from controlled environment yields under semitransparent photovoltaics
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  Should Agrivoltaics Ever Be Decommissioned? How Agrivoltaics Bolster Farm Climate Adaptation Even When Unpowered
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  Transparency effects in agrivoltaics lettuce cultivation using uniform/non-uniform semitransparent photovoltaic modules in controlled environments
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  Impacts of Type of Partial Transparency on Strawberry Agrivoltaics: Uniform Illumination Thin Film Cadmium-Telluride and Non-uniform Crystalline Silicon Solar Photovoltaic Modules
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  Additional value of non-electricity generating services (co-benefits) provided by non-conventional dual use solar photovoltaic systems: A PRISMA review
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  An open-source spectral measurement platform for plant reflectance and material identification
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  Open-Source Photosynthetically Active Radiation Sensor for Enhanced Agricultural and Agrivoltaics Monitoring
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  Effects of Spectral Ranges on Growth and Yield in Vertical Hydroponic–Aeroponic Hybrid Grow Systems for Radishes and Turnips
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  Financial Analysis of Agrivoltaic Sheep: Breeding and Auction Lamb Business Models
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  Experimental impacts of transparency on strawberry agrivoltaics using thin film photovoltaic modules under low light conditions
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  Open-Source Indoor Horizontal Grow Structure Designs
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  Greenhouse applications of solar photovoltaic driven heat pumps in northern environments
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  Solar Energy Modelling and Proposed Crops for Different Types of Agrivoltaics Systems
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  Maximizing Biomass with Agrivoltaics: Potential and Policy in Saskatchewan Canada
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  Energy Policy for Agrivoltaics in Alberta Canada
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  Agrivoltaics in Ontario Canada: Promise and Policy
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  Energy Modeling and Techno-Economic Feasibility Analysis of Greenhouses for Tomato Cultivation Utilizing the Waste Heat of Cryptocurrency Miners
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  Advancing Agrivoltaics within the U.S. Legal Framework: A Multidimensional Assessment of Barriers & Opportunities
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  Low cost climate station for smart agriculture applications with photovoltaic energy and wireless communication
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  Design and Implementation of 3-D Printed Radiation Shields for Environmental Sensors
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  Design of a low-cost mobile multispectral albedometer with geopositioning and absolute orientation
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  Parametric Open Source Cold-Frame Agrivoltaic Systems
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  Impacts of Location on Designs and Economics of DIY Low-Cost Fixed-Tilt Open Source Wood Solar Photovoltaic Racking
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  Open-Source Design and Economics of Manual Variable-Tilt Angle DIY Wood-Based Solar Photovoltaic Racking System
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  Solar photovoltaic wood racking mechanical design for trellis-based agrivoltaics
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  Open-Source Vertical Swinging Wood-Based Solar Photovoltaic Racking Systems
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  Vertical Free-Swinging Photovoltaic Racking Energy Modelling: A Novel Approach to Agrivoltaics
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  Optimal inverter and wire selection for solar photovoltaic fencing applications
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  The potential for fencing to be used as low-cost solar photovoltaic racking
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  Do agrivoltaics improve public support for solar? A survey on perceptions, preferences, and priorities
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  Greener Sheep: Life Cycle Analysis of Integrated Sheep Agrivoltatic Systems
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  Life cycle assessment of pasture-based agrivoltaic systems: Emissions and energy use of integrated rabbit production
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  Conceptual Design and Rationale for a New Agrivoltaics Concept: Pastured-Raised Rabbits and Solar Farming
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  Integrating solar energy with agriculture: Industry perspectives on the market, community, and socio-political dimensions of agrivoltaics
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  A First Investigation of Agriculture Sector Perspectives on the Opportunities and Barriers for Agrivoltaics
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  Open-Source Script for Design and 3D Printing of Porous Structures for Soil Science
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  Agrivoltaic potential on grape farms in India
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  Aquavoltaics: Synergies for dual use of water area for solar photovoltaic electricity generation and aquaculture
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  The potential of agrivoltaic systems
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  Solar Photovoltaic Powered On-Site Ammonia Production for Nitrogen Fertilization
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  Open-Source Photometric System for Enzymatic Nitrate Quantification
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  Open-source manufacturing of polypropylene replacements for peat cups in vertical farming: improvements in life cycle embodied energy, greenhouse gas emissions, labor and operational costs
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  Agrivoltaics Canada

• Coal with Carbon Capture and Sequestration is not as Land Use Efficient as Solar Photovoltaic Technology for Climate Neutral Electricity Production
• Dual use of land for PV farms and agriculture literature review
• sheep
• Israeli white plastic reflectors

• A Farmer's Guide to Going Solar (NREL)
• German guidelines: https://www.ise.fraunhofer.de/content/dam/ise/en/documents/publications/studies/APV-Guideline.pdf
• 2021 review
• Miskin, C.K., Li, Y., Perna, A., Ellis, R.G., Grubbs, E.K., Bermel, P. and Agrawal, R., 2019. Sustainable co-production of food and solar power to relax land-use constraints. Nature Sustainability, 2(10), pp.972-980.
• Retrofitting solar parks for agrivoltaics
• Shading PV
• Alexis' talk at American Solar Grazing Association2021

1. Solar Sheep, Alberta (https://www.solarsheep.ca/)
2. Sun Cycle Farms, Alberta (https://suncyclefarms.com/)
3. Golden Leaf Agrivoltaics, Ontario (https://goldenleafagrivoltaics.ca/)
4. The Lara Cost Farm, Ontario (https://thelaracosta.com/)
5. Arnprior Solar, Ontario (https://www.edf-re.com/project/arnprior-solar/)
6. Lewis Land & Stock, Ontario (https://solargrazing.org/asga-call-29-don-lewis-from-lewis-land-stock-of-ontario-canada/)
7. Nanticoke Solar, Ontario (https://www.opg.com/stories/hundreds-of-grazing-sheep-helping-to-keep-opgs-nanticoke-solar-facility-in-trim-shape/)
8. Western University’s Western Innovation for Renewable Energy Deployment (WIRED) (https://www.appropedia.org/Western_Innovation_for_Renewable_Energy_Deployment_(WIRED))
9. Orchard, Middlesex, Ontario
10. Solar Grazing Map https://solargrazing.org/map/

• Agrivoltaics Canada