THE climate change-induced rains of last summer left millions of people homeless in many parts of Pakistan. While it is correct to put pressure on the international community to pay their share of the climate debt, the seismic nature of the disaster should focus our attention on drawing up our own policy framework so that we can do our bit.
In this article, I propose clean energy alternatives as a means of reducing the fossil fuel footprint in the country, and to make agricultural production sustainable on the basis of self-sufficient energy. A case in point is the increase in the use of tube wells in agriculture since the 1960s, mainly due to government subsidies. It has led to a significant increase in the area irrigated by groundwater. This has resulted in a decline in the area irrigated exclusively by canal water, which reduced by 38 per cent between 1960 and 2015.
Another issue of considerable concern is the high consumption of water by only four crops: wheat, rice, sugarcane and cotton. These major crops consume around 85pc of the total pumped irrigation water, measuring around 51 billion cubic metres per year. This highlights the need for a more sustainable approach to agriculture and irrigation in Pakistan.
The extraction of groundwater in the country relies heavily on non-renewable sources of energy, such as fossil fuels, leading to high levels of carbon emissions. This not only contributes to environmental pollution but also increases the cost of production for Pakistan’s farmers. The energy that is required for the irrigation of the four major crops mentioned here has a footprint of 103 PJ (petajoule), which is equivalent to 2.5 million metric tons of oil. It generates a carbon footprint of 11 billion kilograms of carbon dioxide, which accounts for 6pc of the national carbon footprint. Most of the energy is used by diesel pumps that extract shallow groundwater, accounting for 73pc of the total energy use, followed by electric pumps that extract deep groundwater.
Pakistan can significantly reduce its energy consumption in irrigation.
The factors that determine the energy and carbon footprints for irrigation water in Pakistan vary spatially and temporally, depending on the crop type, crop water requirements, fraction of the gravity-fed and pumped water, groundwater tables, and energy sources for pumping, including diesel, electric and solar energy.
A recent research study has identified 10 hot-spot districts that make up 42pc of the total energy footprint in Pakistan for the irrigation of the four major crops. These hot spots are located in the southern part of Punjab with its dominant wheat-cotton-sugarcane cropping pattern. The identification of the hot-spot districts is particularly important for targeting energy efficiency measures and promoting sustainable irrigation practices. They include: Vehari, Lodhran, Multan, Bahawalpur, Khanewal, Bahawalnagar, Jhang, Rahim Yar Khan, Muzaffargarh and Rajanpur.
By replacing conventional pumping units (25pc of the total pumping units in Pakistan) in hot-spot districts with solar pumps, it is possible to save 42pc of the existing pumping energy in Pakistan. This would be a substantial saving and could also be a worthwhile investment in the long run. If we assume an average unit cost of Rs2m, installing 0.3m solar pumps in the hot-spot districts would require an investment of Rs600bn. Although this is a significant amount, the potential long-term cost savings could be substantial. Within two years, this investment can lead to a reduction of 42pc of the existing pumping energy, which could translate into significant cost savings for the country. Therefore, it seems like a worthwhile investment to consider.
Furthermore, a policy is needed to ensure solar pumping integration with drip and sprinkler irrigation in the sandy areas of the country, such as Thal, Thar, Cholistan, Potohar, southern Khyber Pakhtunkhwa (Lakki Marwat) and Balochistan for high-value agriculture (orchards and vegetables) with strict enforcement of measures to avoid the depletion of precious groundwater.
Next, the areas with cash crops that have shallow groundwater within the canal commands should be brought under precision agriculture, including laser land levelling and improved conveyance and field application efficiency before integrating them into solar-based surface irrigation.
Finally, the water discharge from solar tube wells should be capped based on specific ecology, cropping patterns and the water requirement for the crops. There should be a prior option to focus on the hot-spot districts (with their high energy use and energy footprints) for immediate energy conservation in areas that have irrigated agriculture by solarising the existing tube wells.
By implementing these recommendations, Pakistan can significantly reduce its energy consumption in irrigation and promote sustainable agriculture practices. Indeed, the adoption of renewable energy in the agriculture sector, especially solar-powered irrigation, can bring many benefits to the country, such as reducing carbon emissions, promoting energy independence, and providing reliable energy sources to the farmers. However, it is crucial to approach this issue with a very clear vision and after comprehensive planning that considers the specific context of each region. The adoption of renewable energy should not be seen as a one-size-fits-all solution. Rather, it should be looked on as a tool that needs to be customised and adapted to the needs and realities of each community.
It is, therefore, important to develop short-, medium-, and long-term targets that reflect the specific goals and challenges of each region, and to provide adequate support, such as subsidies and technical assistance, to help farmers and communities adopt this technology successfully. Additionally, it is important to consider the potential unintended consequences of adopting renewable energy, such as over-extraction of groundwater, as well as to develop regulations and incentives that encourage the sustainable use of natural resources throughout the country.
Recently, there has been a lot of research in Pakistan — pilot-scale and feasibility studies, in combination with subsidies, have been initiated at the provincial and national levels — exploring and recommending renewable energy potential. Though these efforts are translated into action slowly at the farm level, solar energy applications in irrigated agriculture should be adopted with clear, short-, medium-, and long-term targets.
The writer heads the Alternative Energy in Agriculture programme at the Climate, Energy & Water Research Institute, National Agricultural Research Centre, Islamabad.
Published in Dawn, March 16th, 2023