Agrivoltaics is the practice of growing crops and producing solar electricity on the same land. Elevated photovoltaic panels create shade patterns while crops continue to use sunlight, soil, water, and nutrients below. This matters because farms often compete with energy projects for land, especially in sunny regions.
A well-designed agrivoltaic system can increase total land productivity by producing food and electricity together.
The main mechanism is controlled sharing of sunlight. Solar panels convert part of the incoming solar energy into electrical energy, while the remaining light and the panel shade change the crop microclimate below. In hot or dry areas, partial shade can reduce heat stress and evaporation, which may lower irrigation needs for some crops.
The best designs depend on crop type, panel height, row spacing, local climate, and farm machinery access.
Key Facts
- Solar panel power output can be estimated by P = ηIA, where η is efficiency, I is solar irradiance, and A is panel area.
- Electrical energy produced over time is E = Pt, where E is energy, P is power, and t is time.
- Land equivalent ratio can be written as LER = crop yield fraction + solar yield fraction.
- If LER > 1, the combined farm and solar system uses land more efficiently than separate crop and solar sites.
- Partial shade can reduce leaf temperature, soil evaporation, and water stress for some crops.
- Panel height, tilt angle, and row spacing control how much light reaches crops and whether tractors can pass underneath.
Vocabulary
- Agrivoltaics
- Agrivoltaics is the combined use of land for agriculture and photovoltaic electricity generation.
- Photovoltaic panel
- A photovoltaic panel is a device that converts light energy directly into electrical energy using solar cells.
- Irradiance
- Irradiance is the solar power arriving on a surface per unit area, usually measured in watts per square meter.
- Microclimate
- A microclimate is the local set of temperature, light, wind, and moisture conditions around a specific place such as a crop row.
- Land equivalent ratio
- Land equivalent ratio compares the combined productivity of shared land with the productivity of separate land uses.
Common Mistakes to Avoid
- Assuming more shade is always better for crops is wrong because plants still need enough light for photosynthesis and growth.
- Ignoring panel spacing is wrong because tightly packed panels can reduce crop yield and block access for people, irrigation systems, or farm machines.
- Treating all crops the same is wrong because lettuce, berries, tomatoes, grains, and corn can respond very differently to shade and heat.
- Calculating solar energy without time units is wrong because power is a rate, while energy depends on how long the panels produce electricity.
Practice Questions
- 1 A set of solar panels has an area of 120 m², an efficiency of 18%, and receives an irradiance of 800 W/m². Use P = ηIA to estimate the electrical power output.
- 2 An agrivoltaic array produces an average of 35 kW for 6 hours. Use E = Pt to calculate the electrical energy produced in kilowatt-hours.
- 3 A farm finds that crops under panels produce 85% of the normal crop yield and the solar panels produce 70% of the electricity of a solar-only site. Calculate the land equivalent ratio and explain whether sharing the land is beneficial.