Reaping a Solar Harvest

The proliferation of solar energy farms worldwide has seen the rapid emergence of agrivoltaics – the parallel development of solar power plants and agriculture in areas with an abundance of both sunlight and arable land. It is a symbiotic relationship with bright prospects.

Reaping a Solar Harvest

By Patricia Seoane da Silva, Senior Research Associate, Lux Research

 

The demand for water, energy, and food is continually increasing and is regionally dependent because of socio-economic factors related to a rising global population, rapid urbanisation, and economic growth. The so-called water-energy-food (WEF) nexus reflects the complex interaction between the three sectors, and is at the heart of sustainable development. 

 

Agriculture is the largest consumer of the world’s freshwater resources, and more than a quarter of global energy consumption is related to food production and supply. Within this context, the installation of solar plants on agricultural land – a concept called agrivoltaics – is gaining traction because of its potential to overcome challenges within the WEF nexus. 

 

Early research indicates that shading from solar panels in an agrivoltaic configuration mitigates water evaporation, reduces plant drought stress, boosts yield, and lowers the operating temperature of solar modules – in turn increasing power output. 

 

Results so far differ to some extent due to the scale of research trials, which depend on specific weather conditions and types of crop species.

Leafy greens and root crops have been found to have high potential for agrivoltaics.
Leafy greens and root crops have been found to have high potential for agrivoltaics.

 

For instance, researchers at Oregon State University concluded that leafy greens and root crops showed the highest potential for agrivoltaics across a variety of climates, whereas other vegetables like tomatoes and peppers are more climate-dependent and require warmer weather. Consequently, the potential advantages of agrivoltaics are likely to differ according to a crop’s regional performance.

 

The same researchers also found that the areas with the greatest potential for agrivoltaics are the western United States, southern Africa, and the Middle East, due to their high levels of solar irradiance. These three locations are also prone to issues surrounding future water availability, further enhancing the value of agrivoltaic systems. 

 

Agrivoltaic systems can simultaneously boost food production, save water, and generate renewable energy.
Agrivoltaic systems can simultaneously boost food production, save water, and generate renewable energy.

Global hotspots

Other emerging sites for agrivoltaic deployments include India and Europe. India has recently seen a rising penetration of solar energy and has the largest area of irrigated croplands in the world, as well as the second largest area of arable land.

 

In Europe, agrivoltaic applications have captured the attention of institutions and industry players including TotalEnergies SE. The French oil major last year signed an agreement to develop solutions for agrivoltaic projects and reached a partnership with InVivo Group, a national union of agricultural cooperatives, to accelerate the development of agrivoltaic solutions. 

 

In China’s Yunnan province, the first wholly-owned photovoltaic project by CLP Holdings Limited – Xicun Solar Power Station – successfully integrated the farming of honeysuckle flowers into its operations, transforming what was previously a sandy wasteland into cultivated farmland. 

 

The solar power plant teamed up with farmers to grow honeysuckle flowers – a crop commonly used in Chinese medicine – beneath elevated solar panels, maximising land use, creating jobs for local farmers, and providing the community with clean energy. 

 

Honeysuckle flowers are grown underneath elevated solar panels in CLP's Xicun Solar Power Station.
Honeysuckle flowers are grown underneath elevated solar panels in CLP's Xicun Solar Power Station.

Bright prospects

Agrivoltaics offers further benefits by integrating solar electricity generation with agriculture production. A study by Fraunhofer Institute for Solar Energy Systems showed that agrivoltaic systems in drylands can simultaneously increase renewable energy production and crop production.

 

Agrivoltaics rely on synergistic interactions associated with factors arising from the WEF nexus to succeed. First, the co-location of solar infrastructure and agriculture is a passive solution to optimise land and water use while increasing the yield and potential quality of crops. 

 

Furthermore, this application relies on mature and relatively inexpensive technologies, and could become an additional revenue stream for farmers that participate in community solar programmes. These types of simple solutions have already proved successful. 

 

For example, floating solar – solar panels mounted on a structure that floats on a body of water – emerged as a relatively simple concept, but reached scale rapidly due to its ability to unlock lakes and reservoirs for power generation.

 

While agrivoltaics is a relatively novel application and more research is needed to fully understand where the opportunities lie among different cropping systems, early indications are positive.

Source: Fraunhofer Institute for Solar Energy Systems (ISE)
Source: Fraunhofer Institute for Solar Energy Systems (ISE)

 

Ongoing development will be critical for its future success. Opportunities for new agrivoltaic systems are meanwhile proliferating as interest sharpens among players in three major interconnected industries – water, energy, and agriculture.