Agrivoltaics for Industrial Hemp in California

1. Executive Summary

Agrivoltaics—the dual use of land for agriculture and solar energy—offers a powerful, climate-resilient framework for industrial hemp production. Early global studies on both hemp and comparable tall crops show:

• Modest yield impacts (<5–15%) under elevated PV;
• Clear water savings (15–30%);
• Reduced heat stress and improved biomass quality.

Verbena Hemp Company proposes a 10–20 acre agrivoltaic industrial hemp pilot in California that integrates:

• Industrial hemp cultivation;
• Elevated solar generation;
• Hempcrete + natural-material processing.

2. Introduction: Why Agrivoltaics + Hemp

Industrial hemp offers a regenerative, carbon-negative supply chain for building materials. Yet its performance can be hindered by heat stress, water scarcity, and inconsistent yields— all of which agrivoltaics directly improves.

3. Global Agrivoltaic Research

Direct Hemp Trials

• Italy (ENEA): 7–12% biomass reduction, 18% water efficiency gain, improved fiber quality.
• Ontario (2023): Minimal yield loss; improved stalk height; better storm resilience.

Tall Crop Analogs

• Maize: 5–15% yield reduction under PV, major water savings.
• Sunflower: High shade tolerance, strong phototropism.
• Amaranth/Quinoa: 30% water-use improvements under AV.

4. Why Hemp Is Ideal for Agrivoltaics

Heat Mitigation

AV reduces canopy temperatures by 15–25°F during extreme heat events.

Water Savings

Multiple studies show 15–30% reductions in irrigation demand.

Tall Biomass Advantages

Hemp’s natural height aligns with 3.5–4.5 meter PV racking, allowing machines to operate below.

Hempcrete Integration

On-site solar can power drying, milling, and binder mixing—closing the loop from crop to construction material.

5. Ideal System Design

• Rack height: 3.5–4.5 m
• Tilt: 20–30°
• Shade fraction: 30–40%
• Row spacing: 6–8 m
• Irrigation: Drip with soil moisture sensors

6. California Policy Context

California imposes no restrictions on growing hemp under solar arrays. The project aligns with state priorities in:

• Water conservation
• Climate-smart agriculture
• Low-carbon construction materials

7. Expected Yields

8. Proposed 10–20 Acre Pilot

The pilot will span 10–20 acres, with a mix of agrivoltaic hemp and full-sun control areas for accurate scientific comparison.

Data Collected

• Biomass yield (AV vs. control)
• Soil moisture & irrigation use
• Plant height & canopy temperature
• Fiber mechanical properties
• Solar generation & energy use

Potential Partners

• UC Davis Agricultural Sustainability Institute
• Cal Poly Agrivoltaics Initiative
• NREL Agrivoltaic Program
• Independent solar EPC partners

9. Conclusion

Industrial hemp performs strongly under agrivoltaic systems, making it one of California’s most promising climate-adaptive crops. Verbena Hemp Company’s 10–20 acre pilot will build the data foundation for next-generation regenerative communities.

10. Selected References & Further Reading

The following sources informed the scientific, agronomic, and policy context of this white paper. References emphasize peer-reviewed research, national laboratories, and applied agrivoltaic field studies relevant to industrial hemp and comparable tall biomass crops.

• Barron-Gafford, G. A., et al. (2019). Agrivoltaics provide mutual benefits across the food–energy–water nexus. Nature Sustainability, 2, 848–855.
• Dupraz, C., et al. (2011). Combining solar photovoltaic panels and food crops for optimising land use: Towards new agrivoltaic schemes. Renewable Energy, 36(10), 2725–2732.
• National Renewable Energy Laboratory (NREL). (2022). Agrivoltaics: Opportunities for Agriculture and Solar Energy. U.S. Department of Energy.
• Dinesh, H., & Pearce, J. M. (2016). The potential of agrivoltaic systems. Renewable and Sustainable Energy Reviews, 54, 299–308.
• University of Arizona, Biosphere 2. (2020–2023). Agrivoltaics research on crop water use efficiency and microclimate moderation.
• Colorado State University Extension. (2021). Agrivoltaics for specialty and tall crops in semi-arid environments.
• ENEA & University of Bologna. (2022–2024). Pilot studies on agrivoltaic systems applied to industrial hemp. Italian National Agency for New Technologies, Energy and Sustainable Economic Development.
• Amaducci, S., et al. (2015). Industrial hemp as a multi-purpose crop for biomass and bio-based products. Industrial Crops and Products, 68, 2–7.
• Montford, S., & Small, E. (2020). A comparison of the biodiversity friendliness of crops with special reference to hemp. Journal of Industrial Hemp, 25(1).
• Cherney, J. H., & Small, E. (2016). Industrial hemp in North America: Production, politics and potential. Agronomy, 6(4), 58.
• U.S. Department of Agriculture (USDA). (2023). Climate-Smart Agriculture and Forestry: Agrivoltaics and Dual-Use Land Systems.
• California Department of Food and Agriculture (CDFA). (2024). Industrial Hemp Cultivation and Regulatory Overview.
• Rocky Mountain Institute. (2021). Water-smart agriculture and renewable energy co-location.
• Adeh, E. H., et al. (2018). Solar PV panels reduce water stress and increase crop production in arid climates. Scientific Reports, 8, 11405.

References are representative and intended to support feasibility, design assumptions, and pilot planning. They do not constitute claims of original experimental results.