The potential of Cambodia’s solar technology market to support farmer-led irrigation

Reservoirs, river and canal systems are among the main irrigation systems used in Cambodia, but there is recognition of the limitations of these systems. Many of the irrigation schemes were built in the 1970s, are run down or are not designed to efficiently support irrigation needs. Thus, there are varied farmer-led mechanisms to access water and convey it to their farms. For example, thousands of irrigators are using diesel pumps for irrigating paddy rice and cash crops. For paddy rice, motorised pumps are used for both water pumping from, and draining into, the irrigation canal system. While useful, pumping also has economic and environmental trade-offs. Recently, the government has been finding ways to systematically address irrigation water scarcity, considering not only large infrastructure investments, but also other modes of irrigation that farmers had already explored. One emerging system in Cambodia is solar irrigation.

Solar technologies are instrumental in revolutionising irrigation systems and sustainable water practices, addressing water and energy scarcity challenges. The significant improvement of solar-powered solutions offers a promising path towards efficient and environmentally conscious irrigation management. It has also been promoted as a way to achieve higher water usage efficiency while reducing operational costs by 30 per cent. The falling price of solar photovoltaic panels in recent years has seen solar-powered pumps emerge as a climate-smart irrigation technology in many developing countries with low access to the national power grid.

In the Mekong region, solar-powered irrigation is underdeveloped. “Getting the right solar technologies to the right people is often complicated by weak supply chains, high costs, poor understanding of local market needs, and lack of after sales service support” says Dr Paul Pavelic from the International Water Management Institute (IWMI). This is why IWMI, the International Rice Research Institute (IRRI) and the International Maize and Wheat Improvement Center (CIMMYT), under the ASEAN – CGIAR Innovate for Food Regional Program, are working with farmers, governmental agencies and solar pump suppliers. One of the programme’s aims is a better understanding of farmer-led irrigation and catalysing suitable options such as solar-powered irrigation to boost smallholder agri-food systems. These can inform future interventions in areas where irrigation is limited.

Solar-powered irrigation technology supply
 

A rapid market assessment was conducted, focusing on mapping solar technology actors and supplies, identifying demand segments and exploring ways to achieve demand-supply matching and linkages. This assessment shows that the government agencies and NGOs are important actors in the supply chain. Since the early 2010s, these actors have championed the introduction of solar-powered irrigation via policy measures and development programs across various provinces in the country. They buy irrigation equipment for farmers. Some also collaborate with entrepreneurs to distribute solar-powered irrigation pumps to individual and groups of farmers, sometimes for free. In some projects, the pumps are bundled with drip irrigation systems to encourage more efficient use of water. Projects, through subsidies, co-financing mechanisms, or, in some cases, free demonstration, create a type of artificial market that can skew the price of solar-powered irrigation systems.

Diverse demand segments
 

Farmers mainly obtain solar-powered pumps via subsidy through the projects. Some wealthier farmers invest in solar powered systems, particularly for farms with an aquaculture component. Real demand segments for solar-based irrigation are, however, diverse. They can be differentiated in terms of the water source, irrigated land area, pump and water application preferences, and capacity to pay for the technology, as illustrated below.

1. Small, mobile, solar-based irrigation systemsappeal to small-scale dry season vegetable production of around 0.2-0.4 ha. This vegetable production is common in rainfed rice systems and home gardens. Most access water through a dug-out well and/or a pond. The system combines a mini movable surface pump and panel (100-200 W). The use of batteries to store energy is preferable as farmers use solar power for multiple purposes, e.g. charging mobile phones or small LED lights. One system costs up to 900 USD. However, suppliers do not prioritise this technology, challenging farmers’ access and investing. One problem encountered by farmers using small solar-based irrigation is the maintenance, technical advisory and repair services for their system. As suppliers are often unable to provide after-sales services to these small systems, the latter may be abandoned if they break down.   
2. Groundwater-based solar irrigation systemstarget relatively large, irrigated farming areas of fruits and/or vegetables, around 1-2 ha or more. They have also been used in aquaculture and rice-fish systems. These farming systems are common in provinces such as Takeo, Prey Veng, Kandal and Svay Rieng, where irrigators have access to good groundwater resources. The systems can be solar-powered, bundled with a 1-3 HP submersible pump, 4-8 panels (≈450W each) and a 50-80-metre-deep borehole. They can also be a hybrid pump using solar power and on-grid electricity, with an inverter. Depending on the type of commodities produced, these systems can bundle with drip or sprinkler irrigation systems as well. The cost can be up to 5,000 USD, depending on their capacity. The private sector suppliers prioritise this demand segment, especially for individual farmers’ investments.
3. Group-based solar irrigation systemstarget the collective use of high-capacity systems shared by farmers with around 10 ha or more cultivated area. Some cost up to 6,000 USD for a system that serves 10 hectares of farm land. These systems use solar-powered submersible pumps from mainly groundwater sources, although some also draw upon canal water. A water supply network to different farms that share the same pump is included, significantly increasing the investment cost. For the private sector companies, this segment can save on installation and maintenance costs while reaching more farmer clients. There are however, potential conflict-related issues regarding water use and irrigation arrangements.    

Thus, there are opportunities through different modalities of solar-based irrigation that are existing in Cambodia. Each has its own dynamics for access and use as well as benefits to farmers.

The way forward for demand and supply linkages
 

Bundling solar-based irrigation with options familiar to farmers can be a way forward. “Drip irrigation arrived in Cambodia nearly 20 years ago and has recently become widespread, especially for vegetables and fruits. Solar-powered irrigation was introduced 15 years ago. Now is the time to combine these two technologies,” says Dr Buntong Borarin, Director of Research at the Royal University of Agriculture, Cambodia. The potential of solar-based irrigation to increase agricultural productivity and enhance climate resilience and adaptation is substantial in Cambodia. To maximise this potential, stronger market demand-supply linkages are recommended to match the right demands with the supply of solar-based irrigation bundles.

New areas for solar technology expansion are opening, which development and policy stakeholders can strengthen. Recently, there has been a rising trend in growing vegetables in net houses, in which drip irrigation is the main method of water conveyance. Linking actual demand with supplyshould capitalise on existing and emerging opportunities to enable investment in solar irrigation.Insights into diverse demand segments are helpful for solar-powered irrigation companies and technicians to target their products and services to the right farmers in the right way. Establishing active sales and service networks at local level is essential for private sector companies to reach more clients.

Enabling the visibility and capacityof the solar irrigation supply chain actors is urgently needed. The capacity to provide a bundle of solar-powered pumps, pre-and post-sale services and financial products is critical to lowering business risks while increasing farmers’ access to and investment in solar irrigation. Suppliers should diversify their solar technology options, including high-quality pumps and their mobility, capacity, battery for storing power and multiple use technologies. Such diversification is necessary to build the market reputation and increase the market share while optimising farmers’ investment choices. Public and private partnerships are essential to connect technology supply and different farmer segments efficiently. “Innovative marketing strategies are needed to incentivise the solar-based irrigation market as marketing and sales are increasingly happening on social media platforms like Facebook, TikTok and YouTube,” says Dr Rica Joy Flor of IRRI.

Innovative financing solutions, such as those being explored for climate finance, are needed to address financing challenges and the unsustainable business environment for solar irrigation. Feasible and tested mechanisms, approaches and tools are necessary if the private sector is to finance pumps. Adequate consideration of biophysical context, value chain dynamics, technology options and local availability of pre- and after-sales services is necessary to develop innovative financing services. For example, climate financing mechanisms may be explored for sustainable solar irrigation. Financing mechanisms should be integrated whenever possible, with the possibility of formal arrangements and investment with financial institutions such as banking systems.

Authors: Thai Thi Minh, Senior Researcher – Innovation Scaling, International Water Management Institute (IWMI), Borarin Buntong, Director of Division of Research and Extension, Royal University of Agriculture (RUA), Paul Pavelic, Senior Researcher – Hydrogeology, International Water Management Institute (IWMI), Lyhour Hin, Researcher, Faculty of Agricultural BioSystem Engineering, Royal University of Agriculture (RUA) and Rica Joy Flor, Scientist II – Innovation Systems, International Rice Research Institute (IRRI). Contact: r.flor@irri.org