A recent United Nations report put Pakistan’s expected population at 336 million by 2050. It means an increased demand for food, water and energy. National Transmission and Despatch Co. (NTDC) estimated in April 2020 an electricity demand of 139,756 MW by 2047 and proposed an investment of more than $69 billion in its base case scenario.
Pakistan has an extensive power generation capacity from renewables and keeping in mind our commitment towards UN Sustainable Development Goals (SDGs) and Paris Climate accords, we have to focus our efforts on renewables. Hydroelectric power generation, despite having tremendous potential, usually comes with some political controversy in Pakistan. That leaves us with solar and wind. Solar power generation is competing with the agriculture sector for land in every corner of the world. All of it demands a set of unique and diversified sources of power.
In 1981, German physicist Adolf Goetzberger proposed that instead of placing the solar panels on the ground, they could be raised 2m from the ground which would make the healthy crop cultivation between these rows possible. Japanese engineer Akira Nagashima established a prototype field in 2004 which had a profit margin 16 times that of just farming the land in 2013 when the Japanese Ministry of Agriculture, Forestry and Fisheries (MAFF) approved the installation of such systems on existing cropland.
There are mainly three ways solar energy generation and agricultural crop production can be integrated. The foremost of all is intercropping plants between the rows of solar panels which can save 14% to 29% water in drought hit areas. The second approach is to install stilt-mounted solar panels at around 4m above the ground at a 25° angle which can be adjusted to increase output. Productivity can be increased 60% to 70% using the Land Equivalent Ratio (LER) method. The third is to put solar panels on the sides of green houses. These types of systems are recommended on islands with little land resources. However, this technique results in a lower crop weight and growth reduction.
According to a 2022 article published on the CleanTechnica platform, globally installed capacity through the Agrivoltaics system has grown from 5 MW in 2012 to around 2,900 MW in 2020. China has a giant 1 GW Agrivoltaic farm on the eastern banks of the Yellow River in the Ningxia Province. The US has been producing record energy levels from renewables and researchers are looking at producing more than a third of national electricity from solar sources by 2035. It is going to require a lot of land area and without any doubt, with intense competition between farming and solar power generation. The answer to this equation is Agrivoltaics, meaning solar panels and food crops can be combined on the same land.
An Oregon State University study estimates that converting 1% of American farmland to Agrivoltaics could meet national renewable energy targets and save water. “Solar Grazing” is also getting popular in the US in which small animals like sheep are permitted to graze in croplands coupled with solar farms. Animals relish the shade that comes with solar grazing for napping and relaxing while diversifying the revenue chain while also keeping the farmland in production.
In Pakistan, there hasn’t been much research over the prospect of Agrivoltaics. National Solar Energy Federation of India (NSEFI) has estimated that putting 1% of the Indian land under agriculture into Agrivoltaic farming has the potential of producing more than 629,000 MW. Pakistan is only producing 1.6% of its demand from solar power. There are vast arid lands in Southern Punjab, Balochistan and Sindh where solar power generation can be coupled with food production to meet the increased demand of both.
Zamen Tahir and Nouman Zafar from Lahore University of Management Sciences published their work last year examining the monthly and daily variations in photosynthetically active radiations (PAR is the portion of the light that plays a role in food production) under various fixed and tilted Agrivoltaic systems. Vertically installed panels facing East-West were found better suited compared to the ones directing North-South on the basis of PAR patterns. They came up with an intercropping scheme for the lettuce/tomato crops that would ultimately minimize yield losses.
The primary constraints behind the lack of an active push toward Agrivoltaics in Pakistan are the same that have halted development in other major fields, with political will ranking at the top. Governments tend to prefer short-term projects so they can reap fruits in electoral politics, sidelining the long-term vision of sustainable development and climate change. We haven’t even witnessed fast-track progress on hydroelectric, solar and wind projects let alone an innovative first-world technology that’s still making its way through the developed world. Another major hurdle is the high cost of the initial investment. A country with an estimated debt-to-GDP ratio of 75% in fiscal 2022 and a projected deficit of 9% of GDP could find it hard to put its money into untested technologies. In the end, it may come down to the private sector to play its part.
Research demonstrates that Agrivoltaics has considerable profit margins compared with conventional farming practices. If accurately optimized, the power produced from these systems can deliver efficiency by powering up irrigation systems and modern farming equipment. A recent surge in global inflation and supply chain issues have renewed focus on the importance of vertical integration of our key economic sectors. Shortages and price hikes of diesel fuel have badly disturbed cotton cultivation this season as we are still heavily dependent on imports to meet our energy needs. Configuring Agrivoltaics in our farming sector can deliver efficient and enhanced crop yields, climate-resilient energy sources and less dependence on foreign energy imports.