Human civilization, today, depends on Energy and food to flourish; however, the demand for these two resources are expanding at an exponential pace. Conventional sources of energy, i.e. Fossil fuel are a limited source and are depleting rapidly, add to that the CO2 emissions as a result of their usage. Biomass was claimed to be a possible substitute for fossil fuel, however, the land area required to replace fossil fuel with biofuels largely exceeds the cropland region of the planet.
Solar energy, on the other hand, is one of the cleanest and most abundant source of renewable energy available but the amount of space it requires for its implementation is a hindrance, particularly in a densely populated country like India where the loss of farmland can cause systemic issues across the economy.
Here is where the idea of co-location emerges that sees the land allocated to solar PV plants utilized simultaneously for agricultural activities. Currently, this concept is being tested across the globe by numerous companies and a positive response has been received so far.
Agro Photovoltaic Model, as the name implies, is a state of art process where cultivation is done in the available land area under the solar PV arrays to control unwanted weed growth.
Why is weed growth a challenge?
Large ground-mounted Solar Photovoltaic Plants are subjected to two key challenges – module cleaning and weed removal. These require regular manual efforts and investments.
Uncontrolled vegetation disrupts maintenance and causes shadows on PV arrays, leading to hot spots and generation loss. It also causes safety hazards as it becomes a haven for reptiles.
Complete cleaning of these unwanted vegetation incurs a higher soiling rate as well as high manpower, thus reducing the production and attracting higher cleaning frequencies. Dry vegetation collected leads to a higher risk of fire. Thus weed removal is a cost and resource burden to any solar project.
Mahindra Susten’s Agro Photovoltaic Model at Tandur, Telangana
Mahindra Susten has undertaken a pilot agro photovoltaic project at the Tandur, Telangana project in collaboration with Kancor Mane, an Indo-French Spice producing Company.
For the agro pv model to work, the panels are mounted sufficiently high to allow the crops planted below to receive almost as much sunshine as they would if the panels were not there, and to permit farm machinery to operate beneath them.
Agro photovoltaic model is a promising solution for increasing both the land use efficiency and the share of renewable energy provided by the agricultural sector.
A study was carried out internally and the 36.6MW CREPL-Tandur plant at Telangana was selected for the on-ground pilot, given its soil texture and frequent vegetation. Further, an onsite feasibility report suggested two crops for cultivation, namely, annatto dye and lemongrass. Based on the water requirement study at site, a variety of lemongrass were selected which were sturdy and utilized very little water.
Lemongrass is known for its oil which has multiple uses in skincare, healthcare, and Asian cuisines. Lastly, the final yield (oil) will be sold to the channel partner which is a win-win; thus utilizing unwanted labour activity on weed removal and paving the way for additional revenue for the next 25 years.
We have also added cultivation of different vegetables like Brinjals, Lady’s Finger, Green chillies and Onions.
Benefits of the Agro PV Model
Adding plants to solar projects offers numerous benefits besides reducing carbon emissions and expanding renewable energy. NREL-funded research found growing native plants could reduce land acquisition costs, reduce weed control costs and slow panel degradation. With more land being devoted to solar energy production, the idea of co-location seems to make both ecological and economic sense.
- Creation of local employment and yield is used for medicinal purposes.
- Improves company’s community relationships.
- Controls soil erosion.
- Visual tapestry and Aesthetic sense.
- From cost activity to profit activity.
- Low operational expenditure, removal of weeds with no additional costs.
- Payback: 1 Year and IRR: 125%.
Solar development is happening on a massive scale. Most projects are approved under non-agricultural barren land in India so that agricultural lands are not compromised. This represents an amazing opportunity for solar project developers to improve agriculture by incorporating agricultural activities under the solar panel while developing energy at the same time. Therefore, solar project sites can adopt dual land and water use to showcase energy and food productivity on the same land. This is a perfect business case for sustainability for solar projects and can be replicated at various sites based on land, soil and plantation requirements.