Le solaire en tant que source denergie dans les systemes agroalimentaires
Le solaire en tant que source d’énergie dans les systèmes agroalimentaires
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Introduction
L’énergie solaire est l’énergie que la terre reçoit du soleil, principalement sous forme de lumière visible et d’autres rayonnements électromagnétiques. L’énergie solaire fait partie des sources d’énergie renouvelable immédiatement disponibles, mais sa disponibilité et ses caractéristiques varient fortement d’une région à l’autre.
Le potentiel d’énergie solaire est plus élevé dans les régions proches de l’équateur et, donc, dans de nombreux pays du Sud. Dans les régions hors réseau en particulier, l’utilisation de l’énergie solaire dans l’agriculture peut considérablement améliorer les moyens de subsistance en ouvrant l’accès à l’irrigation, au refroidissement, au séchage et à d’autres dispositifs de transformation agroalimentaire. Malgré tout le potentiel que représente l’énergie solaire dans ces régions pour améliorer les conditions de vie, de nombreux obstacles empêchent encore les utilisateurs finaux d’adopter cette énergie propre, notamment le manque d’informations et l’accès aux financements. Pour surmonter ces obstacles, plusieurs approches d’intégration de l’accès à l’énergie solaire ont été élaborées. En savoir plus…
Technologies
En fonction du potentiel des ressources solaires et de leur qualité, l’énergie solaire ouvre la porte à différents usages, ce qui a donné naissance à une grande diversité de technologies solaires. Celles-ci peuvent être passives ou actives, en fonction de la manière dont le rayonnement solaire est capté, converti et distribué. Les technologies solaires actives comprennent les systèmes photovoltaïques solaires et thermiques solaires qui convertissent le rayonnement solaire en énergie utile. Les techniques solaires passives consistent à concevoir les bâtiments, les matériaux et les espaces de manière à optimiser l’utilisation de l’énergie solaire, par exemple, en orientant un bâtiment vers le soleil ou en sélectionnant des matériaux présentant de bonnes propriétés d’isolation ou de conductivité thermique. En savoir plus…
L’énergie photovoltaïque solaire peut être utilisée pour alimenter les pompes des systèmes d’irrigation (voir la section suivante), améliorer les rendements agricoles et économiser les coûts associés à d’autres carburants comme le diesel. Elle peut également alimenter des réfrigérateurs (voir ci-dessous), pallier le problème des coupures de courant qui interrompent la chaîne du froid, améliorer l’accès à des équipements de refroidissement dans les régions hors réseau et limiter les pertes post-récolte. En savoir plus…
L’énergie thermique solaire est utilisée dans les processus de transformation agroalimentaire comme le séchage. Contrairement au séchage au soleil, le séchage solaire évite que la récolte ne soit contaminée par les impuretés du sol et accroît l’efficacité énergétique, qui peut également être renforcée en utilisant l’énergie photovoltaïque pour alimenter des systèmes d’aération artificiels.
Technologies à énergie solaire pour l’irrigation
Parmi les énergies renouvelables, l’énergie solaire est l’option la plus attractive pour l’irrigation. Avec la baisse substantielle du prix des modules solaires ces dernières années, les systèmes d’irrigation à énergie solaire (SPIS) sont devenus beaucoup plus intéressants d’un point de vue économique.
Pompe à eau à énergie solaire
There are different approaches of integrating renewables in pumping systems. The solar powered water pump, running on photovoltaic energy, shows especially good results in equatorial regions, where insulation is highest all year long. It uses solar energy to pump up water from the source to an elevated storage tank. Once water is needed for irrigation, it is released gravitationally at a certain pressure dependent on the height difference from the tank to the irrigated area, which can be regulated by pipe diameter and length, and the type of emitters employed. As solar panels become cheaper, this technology is increasingly accessible to most smallholder farmers in the Global South, allowing expansion of agricultural production to originally off-grid areas, and enhancing stepwise rural electrification through mini-grid projects. Read more…
Micro-centrales solaires pour l’irrigation à petite échelle
However, despite the abundance of solar resources in countries of the Global South, a lack of information and of financing options hinders especially smallholder farmers from adopting solar-powered irrigation systems. In Senegal, farmers currently use the labour-intensive method of flood irrigation with wells and buckets, or cost- and energy-intensive diesel-powered motor pumps. Nevertheless, the country has immense solar resources that can be used to provide clean energy for irrigation practices. Earth Institute’s solution allows a small group of farmers to use a central solar energy unit to power multiple AC pumps for irrigation. This approach takes advantage of the benefits of solar without the high costs associated with DC-powered pumps and battery storage. Being accessed by farmers with prepaid electricity cards, this micro solar utility allows customers to cover their appliance loans in small payments, overcoming the major obstacle that hinders farmers from the adoption of the technology, which is Financial Instruments and Financing for Sustainable Agrifood Systems. The three shared systems that were implemented until 2016 served 21 farms, which have experienced 29 percent average increase in agricultural production, and resulted in 24 tons of CO2 equivalent. The project is now seeking partnerships for scaling up, adoption and local maintenance contracts. Read more…
Technologies à énergie solaire pour le refroidissement
Dans les climats chauds, le refroidissement est un élément essentiel des chaînes de valeur agricoles. Les régions concernées ont rarement accès à un réseau électrique fiable (fondamental pour la chaîne du froid), ce qui signifie que les produits ne peuvent pas atteindre les marchés locaux et mondiaux dans des conditions acceptables. L’utilisation de l’énergie solaire pour alimenter des technologies de refroidissement est donc une solution particulièrement intéressante pour augmenter les revenus des agriculteurs tout en réduisant les pertes post-récolte.
Machine à glace solaire
The solar ice maker uses solar energy to feed a refrigeration system where water can be frozen and used in refrigeration devices. This technology can find different kinds of uses: it can be used for milk chilling, cooling down vegetables during harvest, and much more. Examples of different value chains where solar ice making devices have been employed are listed further below under Case Studies. Read more ...
Refroidisseur à eau
Another cooling example that involves ice making is the Water Chiller. Using a renewable energy source like solar energy it can freeze water and create cold air that is blown to a storage room for commodities like vegetables.
Technologies à énergie solaire pour le séchage
Le séchage permet d’empêcher la détérioration des produits périssables tels que les fruits, les légumes, les tubercules ou même la viande et le poisson, grâce à l’énergie thermique du soleil. Dans les pays qui ne disposent pas de technologies industrielles de conservation, des solutions simples comme le séchage solaire sont très prometteuses.
Le séchage solaire consiste à accumuler l’énergie du soleil à l’intérieur d’un dispositif de collecte de la chaleur, afin de créer un flux d’air chaud par convection naturelle ou forcée. Il utilise donc l’énergie thermique du soleil. Lorsqu’il passe sur les aliments, l’air chaud et sec élimine l’humidité, qui se dissipe dans l’atmosphère par une cheminée installée à l’autre extrémité. En fonction des caractéristiques du produit final, le séchage solaire peut être plus ou moins sophistiqué. Les séchoirs solaires traditionnels utilisent la convection naturelle de l’air chaud, tandis que les approches innovantes sont équipées d’un ventilateur à énergie photovoltaïque qui déplace l’air artificiellement à l’intérieur du séchoir pour accroître son efficacité. Contrairement au séchage conventionnel au soleil, le séchage solaire a généralement lieu dans un endroit clos afin de protéger les produits contre les impuretés extérieures. La complexité des différents types de séchoirs solaires varie : le séchage direct, le séchage indirect, le séchage mixte et le séchage hybride sont les principales solutions disponibles en fonction des besoins. En savoir plus…
Séchoir solaire boîte
The solar box dryer consists of a box with a glass cover on top, inclined at an angle to allow maximum solar radiation to enter. The inner walls of the box are covered with an aluminium sheet with black coating to absorb the radiation entering through the transparent top. The products to be dried are spread on three trays made of stainless-steel wire mesh inside the box. At the lower part of the construction, a rectangular opening at the front wall allows the entrance of air, which through convection enters the box, dries the products, and leaves with the extracted moisture through a chimney made of galvanized iron sheets at the top. It has a small capacity and the drying rates are relatively slow, leading to discoloration of the products, which makes this simple technology suitable for domestic but not commercial use. Read more…
Séchoir solaire armoire
A little bit more complex than the solar box dryer is the relatively more expensive solar cabinet dryer. It consists of two parts: a collector to heat the incoming ambient air using solar radiation and a drying chamber in which food to be dried is spread on a number of trays on different layers. Using glass wool for insulation and aluminium and galvanized iron for heat conduction, the dryer allows indirect heating, which is recommended for drying herbal products, usually sensitive to direct sunlight. In contrast to the solar box, the cabinet dryer is recommended for community use and small-scale income generating industries. Read more…
Séchoir solaire tunnel
While the above-mentioned technologies use air circulation uniquely from natural convection, the solar tunnel dryer includes a small blower running on photovoltaic energy to force air circulation through the solar collector and the drying chambers. Arranged in the form of a tunnel, dryer boxes and solar collectors capture solar energy and heat the product on the trays, while the air forced through the tunnel removes the moisture even under unfavourable conditions. These dryers are recommended for large scale drying for commercial uses. Read more…
Séchoir hybride solaire-biomasse armoire
The hybrid biomass-solar version includes a biomass stove installed adjacent to the collector system of the basic solar cabinet dryer. Using a supplementary fuel as biomass can enhance the drying capacity of the simple solar cabinet dryer, allowing higher drying temperatures, recommendable for drying fish and meat products. Read more…
Acteurs et innovations
Différents innovateurs ont développé et adapté les technologies présentées ci-dessus aux besoins locaux. La résolution des principaux obstacles qui empêchaient l’adoption de dispositifs à énergie solaire a incité les acteurs à trouver des solutions innovantes facilitant l’accès à toutes sortes d’utilisateurs finaux. Cette section présente des innovations pour l’irrigation, le refroidissement, le séchage et d’autres technologies de transformation agroalimentaire et comprend un chapitre consacré à des solutions innovantes pour l’adoption de technologies à énergie solaire.
Innovations à énergie solaire pour l’irrigation
Plusieurs innovateurs ont démontré tout le potentiel de l’énergie solaire pour les techniques de pompage et d’irrigation. Les approches créatives vont des systèmes d’irrigation hydroponiques solaires aux modèles de paiement à la carte à bas coût et facilitent l’accès dans les régions ne disposant pas d’une alimentation électrique fiable. L’utilisation de l’énergie solaire est particulièrement plébiscitée par les petits exploitants des pays du Sud où le rayonnement solaire est une ressource abondante et gratuite.
Pompes à énergie solaire pour améliorer l’irrigation
iDE and its partners have developed a new product category of solar powered pump for irrigation. The so-called Sunflower pump includes a highly efficient piston pump powered by an 80-watt PV panel, featuring a 40 % reduction in weight and volume while retaining its efficiency. Meant to help smallholder farmers increase their production and reduce the involved costs for labour and the use of other fuels, the technology development is however only one component of bringing the solar pump to scale. IDE has identified five key factors needed to bring a clean irrigation solution to scale, including the use of an appropriate technology, a viable business plan, an accompanying finance model, an established supply chain and marketing and educational resources. Read more…
Initiative d’agriculture verte hydroponique
The Jordanian innovator ECO Consult first won the Powering Agriculture Award in 2013 for the development of an integrated hydroponic irrigation model combined with photovoltaic farming. This model not only allows the saving of energy costs but also of water resources, which are scarce in Jordan. Since 2013, the interest among farmers and households in Jordan has grown significantly with this technology promising an increase of agricultural produce and new sources of income and employment opportunities. Read more…
Irrigation à bas coût, facturée à l’usage, basée sur des chariots d’irrigation solaires
In India, where water availability for irrigation depends on monsoon patterns, it is necessary to pump ground water in order to keep growing and producing, and thus generating income. Given a lack of electricity access, the most reliable energy source for pumping is diesel fuel, which has many drawbacks (environmental pollution, ever-increasing costs, among others). With the purpose of avoiding these obstacles to farmer’s economic prosperity, Claro Energy has come up with a pay-per-use irrigation service that uses a portable solar pump. Using a pre-paid card system, farmers can remotely activate affordable, convenient and on-demand pumping service with no upfront capital costs that can irrigate larger amounts of farmland during the dry season. Furthermore, the funds saved can be invested in more efficient technologies, increasing farmers’ productivity and income while decreasing GHG emissions. Read more…
Irrigation solaire performante et abordable pour les petits exploitants
Another pay-as-you-go (PAYG) model has been adopted by the Kenyan innovator KickStart: as solar-powered irrigation technologies still remain expensive in Kenya, adopting a PAYG model allows flexible financing options, which not only make this technology affordable for poor smallholder farmers, but also increases the awareness of clean energy by mainstreaming accessibility. This turns out in a higher demand for sustainable energy, and thereby encourages financing institutions to invest in this kind of technologies, enabling the transition from rain-fed subsistence farming to year-round commercial agriculture. Transforming food and income security of smallholder farmers and broader rural communities, the PAYG model helps people lift themselves out of poverty and allows expand smallholders’ role in water management. Read more…
Systèmes de fertilisation et d’irrigation goutte-à-goutte photovoltaïques
As water resources are scarce in the MENA region, the inefficient use of irrigation water and fertilizers for crop production have large impacts on soil health. In order to ensure a sustainable use of water and soil, the Italian NGO Institute for University Cooperation (ICU) has supported the promotion of a solar-powered drip fertigation system in Jordan and Lebanon. This has allowed farmers to cultivate larger areas as more water is available for irrigation, and to safeguard soils from salinization, since fertilizer application becomes more efficient, which also saves the farmers money and thereby increases their income. The result has encouraged local partners onsite to invest in this promising innovation. Read more…
Intensification de la distribution de kits d’irrigation agro-solaires personnalisés aux petits exploitants
Only 6 percent of African arable land is under irrigation, while climate makes the majority of the continent unsuitable for rainfed cultivation. This leads to low crop yields and a generalized disconnection from the agriculture value chain. However, the few farmers who irrigate rely on expensive diesel pumps or carry the water by hand. This has led the innovator SunCulture to recognize the potential of solar-powered irrigation, and to develop the AgroSolar Irrigation Kit (ASIK), for cheaper and easier access to solar-powered irrigation. SunCulture has started training technicians, agronomists and hopes to expand the distribution partnerships across the entire continent. Read more…
Micro-réseaux d’énergie renouvelable pour les écloseries hors réseau et les communautés environnantes
In Bangladesh, off-grid fish hatcheries rely extensively on diesel and kerosene to provide electricity for water pumping and lighting. Both energy sources are costly, pollute the environment and threaten the food chain and human health. The International Development Enterprises iDE have developed a business model attractive for investors to promote a clean energy solution: the implementation of solar and hybrid solar/wind micro-grids. This innovation does not only increase and enhance the productivity of the hatcheries but also provides domestic energy access, increasing the hours of lighting and allowing the use of fans and refrigerators. Read more…
Pompe Sunflower : pompes d’irrigation solaires financées sur les actifs pour les petits exploitants
The PAEGC innovator Futurepump developed the SunFlower Pump, which is an easy-to-maintain solar irrigation pump, built around a simple piston pump arrangement. In collaboration with Kenya’s Equity Bank, which has made the product available to customers through consumer financing, Futurepump has established a loan system making the Sunflower Pump become cheaper and easier to access by Kenyan smallholder farmers, allowing an increase of nearly 50 % of agricultural production by irrigating their fields. Read more…
Micro-centrales solaires pour l’irrigation à petite échelle
As irrigation practices in Senegal are often labour- or cost-intensive, the Earth Institute at Columbia University, partnering with the MDG Center West and Central Africa (WCA) has developed a central solar energy unit to power multiple alternate current (AC) pumps for irrigation. The proposed solution takes advantage of the benefits of solar without the high costs associated with direct current (DC) powered pumps and battery storage. Using prepaid electricity cards, small farmers can easily afford this PAYG irrigation service, resulting in higher revenues from lower costs and higher production rates. Read more…
Innovations à énergie solaire pour le refroidissement
Sur la base des mêmes principes que ceux énoncés ci-dessus pour la machine à glace solaire, des approches créatives ont été mises au point pour le refroidissement solaire. Elles permettent de préserver les aliments dans les régions sans accès fiable à une électricité abordable et, donc, de réduire les pertes post-récolte et d’améliorer la sécurité alimentaire. Elles favorisent également la hausse des revenus et l’indépendance, et participent à l’atténuation du changement climatique.
ColdHubs
ColdHubs are large walk-in storage rooms for fresh vegetables which include a refrigeration system that runs on solar power. Developed by ILK Dresden and the Smallholder Foundation, this innovation can save huge amounts of perishable food (storage capacity of up to 2 tons) and works off-grid, being especially suitable for rural areas, where large amounts of food need to be stored before joining the market. Read more…
Innovations à énergie solaire pour le refroidissement
The University of Hohenheim developed an approach that allows entrepeneurs, engineers, etc. in the Global South to assemble their own solar cooling systems, adapted to the local context and needs. The vendors and manufacturers of these simple but effective systems only need to import one piece while all other material can be obtained from the domestic market - making these systems much more cost-effective than comparable refrigeration systems that are wholly imported from abroad. Do It Yourself - Solar Cooling Units
Innovations à énergie solaire pour le séchage
Différents acteurs et innovateurs ont adapté les technologies de séchage ci-dessus aux besoins spécifiques de différentes chaînes de valeur. L’utilisation de l’énergie photovoltaïque solaire améliore l’efficacité énergétique et permet aux populations les plus pauvres des zones rurales d’accéder à l’électricité. Elle réduit en outre les coûts de conservation des aliments, ce qui permet de limiter les pertes post-récolte et d’améliorer les revenus au moyen de processus à valeur ajoutée.
Séchoir solaire tunnel
Cette innovation permet de mettre en place des conditions de séchage sûres et efficaces basées sur l’énergie solaire : le séchoir solaire tunnel a été conçu par l’université de Hohenheim (Allemagne) et l’Institut international de recherche sur le riz (IRRI). Ce séchoir se compose d’un tunnel plastique de 15 à 26 mètres de long dans lequel le riz est étalé. Transparente, la partie supérieure du tunnel laisse pénétrer les rayons du soleil, ce qui fait monter la température à l’intérieur pour sécher le produit. La chaleur est répartie uniformément par des ventilateurs à énergie solaire qui font circuler l’air pour éliminer l’humidité. Pour optimiser l’opération, le riz est régulièrement retourné au moyen d’un rouleau. Le séchoir tunnel est actuellement en cours d’optimisation sur le plan énergétique et fait l’objet d’essais dans différents pays. Son coût se situe entre 1 200 € et 3 400 €. En savoir plus…
Développement du GrainSafeTM Dry (GSD)
En collaboration avec l’Institut international de recherche sur le riz (IRRI) et l’université de Hohenheim, GrainPro, Inc. a conçu le GrainSafeTM Dry (GSD). Le GSD combine séchage en espace clos et stockage hermétique des grains. Le séchage en espace clos a pour but de contrôler l’humidité relative de l’air de séchage afin que toutes les couches de grains atteignent le taux d’humidité à l’équilibre. Pour y parvenir, un ventilateur à énergie solaire souffle de l’air chaud dans la masse de grains depuis le bas de l’appareil, jusqu’à ce que le niveau d’humidité souhaité soit atteint. Avec le stockage hermétique, les grains sont enfermés dans un conteneur étanche à l’air, fabriqué avec des matériaux présentant une très faible perméabilité à l’oxygène, ce qui les protège des insectes et d’une réabsorption d’eau. La combinaison du séchage en espace clos et des propriétés de stockage hermétique permet de faire sécher les aliments et de les stocker dans un environnement protégé. L’intégration d’un contrôleur de séchage accroît l’efficacité énergétique en adaptant la vitesse du ventilateur au taux d’humidité relative. D’une capacité de 1 à 5 tonnes de riz pour un prix prévu de 1 100 $, le GSD doit encore être testé et optimisé avant qu’un prototype commercial puisse être développé. En savoir plus…
Innovations à énergie solaire pour d’autres dispositifs de transformation agroalimentaire
Les impacts significatifs de l’énergie mécanique destinée à la transformation des aliments sur la création de revenus et sur la réduction de la pauvreté sont révélateurs du vaste potentiel des systèmes énergétiques durables en zone rurale. Les innovations suivantes montrent que l’adoption d’énergies renouvelables à différentes étapes de la transformation des produits alimentaires permet de remplacer les sources d’énergie traditionnelles et de réduire les coûts tout en améliorant l’efficacité. Les multiples approches évoquées, qui vont des systèmes d’aération pour l’aquaculture aux presses à huile solaires, ont différents impacts sur la société et l’économie locales.
Évaluation locale d’un système d’aération passif pour l’aquaculture
Aquaculture accounts for a significant percentage of the GDP of many low-income countries. By artificial aeration, the level of dissolved oxygen in the deeper water layers of the fish farm’s ponds can be increased, leading to higher fish yields and enhanced food security. However, using a conventional electrical pump for artificial aeration can become very costly. The University of Toronto and its partners have introduced a passive aeration system that only uses solar thermal energy. The technology is applied at the bottom of the pond, mixing the water and resulting in higher levels of oxygenation, an improved water quality and higher yields. Since using solar thermal energy, the system proves much more affordable than traditional ones. Read more…
Centrales solaires pour la transformation agroalimentaire
The Village Infrastructure Angels (VIA) started the mission of making poverty-alleviating infrastructure affordable to everyone in 2012. As energy plays a key role in agricultural production, especially in processes like milling, introducing solar mills in rural areas through microfinancing programs has increased income and saved manual labour. VIA have deployed different types of solar mills to different countries of the Global South, improving the livelihoods of farmers, especially women, who are often involved in manual processing. Read more…
Presse à huile à énergie solaire pour les graines de sésame
This solar-powered oil press allows off-grid oil extraction of sesame seed. Being a counter-seasonal crop that requires little fertilizer or pesticide inputs, sesame grows under harsh weather conditions and can promise higher income when processed appropriately. Designed by the University of Hohenheim, the solar-powered oil press for sesame seed includes a solar panel connected to a control unit which calculates the optimal operational setting dependent on seed moisture content and the current weather conditions, increasing its energetic efficiency. Although the price of the solar-powered unit reaches between € 8,000 and € 13,000, sesame, as a cash crop, allows a payback period of 4 months when the mill is run during the harvest season. Additionally, as a by-product of the oil extraction, the seed cake can be sold as animal fodder. Read more ...
Solutions innovantes pour l’adoption de technologies à énergie solaire
Dans les pays à faible revenu, l’adoption de technologies à énergie solaire peut s’avérer compliquée. Le manque d’informations et l’absence de ressources financières ou d’accès à des options de financement sont les principaux freins à la transition vers les énergies renouvelables. Des approches innovantes ont été élaborées pour surmonter ces obstacles et faciliter la mise en œuvre de l’énergie solaire dans les systèmes agroalimentaires.
Accélérateurs agricoles et micro-réseaux solaires communautaires financés par le secteur privé
Small-scale producers from low-income agricultural communities are among the most vulnerable actors in agricultural value-chains in Guatemala. Suitable technologies, including irrigation and cooling facilities are readily available, but the lack of affordable energy or financing options to invest in clean energy are among the constraints that prevent producers from accessing them. The Universidad del Valle Guatemala (UVG), a non-for-profit secular university has partnered with Development Ventures and Greenergyze, S.A. to develop an innovative approach which aims creating access to low-cost utility companies for ‘off-grid’ agricultural communities. The so-called Community Accelerator consists of a localized photovoltaic (PV) mini-grid that will be operated by a local for-profit service provider company that also provides agribusiness service. This “utility in a box” approach is designed so that private sector financing can be used to fund the Accelerators, making this clean energy solution scalable without additional donor funding. Read more…
Études de cas
Cette section présente différentes expérimentations menées sur les technologies et innovations évoquées ci-dessus dans différents environnements des pays du Sud. Sources de feedback et d’informations de terrain très utiles pour les innovateurs et les experts, ces études de cas prouvent également que les innovations solaires peuvent améliorer les rendements et les revenus.
Études de cas sur les technologies à énergie solaire pour l’irrigation
Les SPIS ont été adaptés à toutes sortes de caractéristiques géophysiques, jusqu’à permettre l’instauration de pratiques agricoles là où la culture n’avait jamais été possible auparavant. Les études de cas qui vont suivre montrent comment des zones arides ayant accès à des nappes phréatiques ou à d’autres sources d’eau peuvent utiliser des SPIS pour rendre la production d’aliments plus efficace et améliorer ainsi la sécurité alimentaire.
Systèmes d’irrigation à énergie solaire en Égypte
Egypt’s agricultural sector employs 54 percent of the country’s population. Yet, the traditionally used areas for crop cultivation close to the Nile are being replaced for living, outsourcing agriculture to the remote areas in the arid desert. Due to the geophysical conditions of the region, constant irrigation is required to keep food growing. However, as electrification for water pumping is too expensive, diesel prices are rising, and require transportation to the cultivated areas, solar water pumps are the only way to go. The initiative RaSeed (called into life by the German development programme “Agricultural Water Productivity as Adaptation to Climate Change”) aims to promote the use of PV systems, targeting farm specific optimization of drip irrigation systems (as soils are very sandy), providing high quality solar energy technology and training in Egypt. Given that most farms in Egypt are in remote desert areas, polycrystalline cells have a better cost-efficiency ratio. However, as this system does not provide a backup power source, three different and more advanced solar pump systems were made available: 1) combining solar energy with batteries for excess energy storage (battery based system ), 2) a combination of solar and diesel power (solar fuel saver system ) or 3) a variable speed drive that connects and regulates PV panels and the diesel generator. The latter is the most cost efficient and most adequate for the Egyptian agricultural sector. Read more…
Étude de cas au Kenya – Ongata-Rongai
In some remote areas in Kenya, grid connection is not reliable enough to run irrigation systems without a back-up generator. This has led the Centre of Alternative Technologies (CAT) in Kenya to pilot a highly efficient hydroponic irrigation system running on solar power (for more information, see Tools & Technologies). Integrated with a reverse-osmosis mechanism for nutrient supply, a tracking system is used for constant feed, saving up to 50 percent of the electricity costs. The system is especially interesting for intensive farming where landholding is limited and soils have a low quality. However, capital and operational costs are high, and due to unreliable grid power supply, production losses are also at risk, as the tracking system is essential for continuous water flow. Furthermore, PV panels need to be protected against theft, and under the local conditions, lettuce is the only suitable crop. Read more…
Systèmes de pompage photovoltaïques (PV) pour l’irrigation
Despite being a technically mature technology, photovoltaic pumping systems lack widespread expansion due to the initial investment costs, especially for small-scale farmers, and the technical know-how required for installation and maintenance. However, once these problems are solved, PVP irrigation can improve agricultural production and increase employment and revenues. This article showcases the efforts made in different regions in order to help establish PVP irrigation. Read more…
Étude de cas par pays – Chili
In the 1980s, the electricity sector in Chile has gone through a process of privatisation and liberalisation. However, small and medium-size farmers have been subsidised, also when using solar water pumps, including up to 90% of investment costs. This has led farmers to form unrealistic expectations about obtaining systems at below-market rates., preventing a market-oriented dissemination of SPIS as subsidies continue. Within the scope of the existing subsidy scheme, about 1,500 solar irrigation pumps have been installed. But the standardised and limited system kits supported by Chilean government subsidies only seldom meet the exact requirements of the target farms, leading to complaints from the farmers, as their solar pump delivers too little water. They also miss the instant high pressure and water flow they are used to from grid supplied electric and diesel engine driven pumps.
Étude de cas par pays – Inde
Grants and subsidies for SPIS technology promotion and demonstration are provided by the Indian government and international donors. 50,000 solar powered pumping systems were installed in 2015. The government uses a combination of subsidy, credit and technical support to promote PV irrigation. An important conclusion is that technical and agronomic assistance should preferably be offered to farmers from one source (one institution) to also facilitate the introduction of PV-powered drip irrigation systems and improved irrigation techniques. In recent years, the Indian private sector started offering SPIS components, and now all main components are produced locally, creating employment in a new sector. Some manufacturers also provide farmers with turn-key solutions, which definitely contributed to better overall system efficiency and performance of the technology. Irrigation water is free of charge and water quality is good. However, groundwater level is constantly falling, which may lead to environmental problems in the near future.
Étude de cas par pays – Kenya
Within the Rural Electrification Master Plan (REMP) remote public buildings are equipped with solar PV systems. However, solar-powered irrigation receives no specific support so far. Recently, first private companies started developing the Kenyan market and installed a few hundred SPIS. The main purpose of solar water pumps in rural areas is to secure drinking and livestock water supply. These systems are often sponsored by international donors. In order to bridge grid power failures and to reduce their monthly electricity bill, a number of flower farms and tea plantations have been willing to invest in solar solutions. Although the advantages are evident, the purchase decisions in Kenya still is taken in favour of competing conventional energy systems, as the perception persists that PV is too expensive. The Kenyan company SunCulture offers the cost-effective AgroSolar Irrigation Kit, combining solar pumping technology with a highly efficient drip irrigation system that makes it cheaper and easier to start farming.
Étude de cas par pays – Maroc
The International Finance Corporation (IFC) conducted a market assessment in Morocco and identified a solar pump market poised for rapid growth in the medium term. The leading manufacturer Lorentz is leading the local SPIS market and sells about 2,000 pump/controller units per year. The Moroccan SPIS market is mainly driven by small to medium-size private farmers who produce cash crops for the local market and for export. The use of efficient irrigation systems is supported by the government through a subsidisation programme (Plan Maroc Vert). SPIS, however, are only promoted by tax incentives. Although the electrification rate of Morocco is above 95 %, most farmers want to reduce their electricity bill and go for solar power, as grid electricity for irrigation is already more expensive, leading to disconnect their electric pumps and driving the Moroccan solar pump market.
Études de cas sur les technologies à énergie solaire pour le refroidissement
Un nombre croissant de technologies de refroidissement basées sur les énergies renouvelables sont utilisées à différents stades de la chaîne de valeur agricole, améliorant ainsi la situation économique des petits exploitants des pays du Sud. Les études de cas suivantes offrent un aperçu de la diversité des solutions ainsi que des bénéfices offerts par la mise en œuvre en zone rurale de technologies de refroidissement adaptées au changement climatique.
SunDanzer : réfrigération à énergie solaire pour les exploitations laitières kenyanes
In Kenya, 85 percent of the dairy farms do not have access to refrigerated storage and transportation due to limited electrification in rural areas, leading to dramatic losses from milk spoilage. SunDanzer together with Winrock International have developed an affordable small-scale portable cooling system: the photovoltaic refrigerator (PVR) runs on solar energy and uses phase-change materials – substances capable of storing and releasing large amounts of energy – and therefore needs no battery. Additionally, the innovators have developed milk can blankets to retain the temperature during transportation. 60 solar-powered milk cooling refrigerators have been installed so far in Kenya, 2 in Rwanda. Users of SunDanzer’s refrigerators have stated that the technology has delivered many benefits, including increased financial security for households, increased food preservation, and saved time, added to household income. Read more…
Réduction des pertes de lait via le refroidissement à énergie solaire
10 billion USD worth perishable food is wasted annually in India because of unreliable cold-chain supply networks. Especially in farming areas and villages, the lack of reliable electricity to run refrigeration systems is the main problem. India being the largest consumer and producer of milk in the world, Promethean Power Systems together with Hatsun Agro and Orb Energy have developed a solar milk cooling system that uses an innovative thermal energy battery pack. Charging on intermittent power sources such as solar power and/or a few hours of grid electricity, it allows changing the local food waste situation considerably. Read more…
Refroidissement solaire SunChill pour la préservation horticole
An innovation designed by Rebound Technologies (United States) aims to reduce post-harvest losses and enhance food consumption quality. The first versions of the SunChill cooling system have been tested in Mozambique and after being validated, a commercialization and expansion to the market is planned. The solar off-grid refrigeration system allows to immediately cool down food during harvest and provides continued product cooling at markets or central processing facilities. SunChillTM transforms 50 °C solar thermal energy into 10 °C refrigeration, doubling shelf life and creating access to nutritional fruits and vegetables. Also, manufacturing and service-based employment, leading to additional income, is expected to increase. By the end of the project, Promethean sold over 600 units, enabling 25,000 dairy farmers to chill their milk without diesel generators to get their milk to the market safely. Read more…
Refroidissement solaire du lait au moyen de bidons isolés
Milk produced on small- to medium-scale farms is usually transported to milk collection facilities. The spoilage caused by bacterial growth during transportation due to warm temperatures leads to milk being refused by vendors. Furthermore, many farmers do not sell their evening milk to the collection centres, as it cannot be stored adequately overnight. Instead, they sell the milk to neighbours or use it themselves. This can increase the on-farm losses and reduce income. The solar milk cooling system developed by the University of Hohenheim (Germany) uses solar energy for ice production. The produced ice is used to cool the milk by putting it into an ice-compartment of an insulated milk can. This system allows lower temperatures during transportation and overnight storage, increasing the farms production and income. On-field implementations have taken place mostly in Tunisia (10 installed systems), Kenya (4 installed systems), and Colombia (also 4 installed systems). Read more…
Études de cas sur les technologies à énergie solaire pour le séchage
L’adaptation du séchoir solaire aux besoins spécifiques de chacune des chaînes de valeur agricoles a permis d’utiliser cette technologie dans de nombreuses parties du monde, dans des conditions d’exploitation très variées. Les études de cas évoquées ici ne représentent qu’une fraction des possibilités du séchoir solaire et montrent que les approches de séchage innovantes peuvent améliorer la qualité des produits et donc les revenus des agriculteurs. Issus de différentes chaînes de valeur du monde entier, les exemples témoignent de la grande adaptabilité de cette technologie et de son important potentiel d’amélioration des moyens de subsistance.
Séchage solaire moderne en Afghanistan
Le séchage des aliments est une méthode couramment utilisée en Afghanistan pour conserver les produits comestibles. Toutefois, les pratiques de séchage traditionnelles, qui consistent à placer les aliments sur des surfaces planes telles que les toits, exposent les produits à la poussière, à la saleté et aux insectes. En collaboration avec l’Afghan Bedmoschk Solar Center e.V., le projet de séchage solaire moderne (Modern Solar Drying) a adapté le séchoir solaire tunnel de l’université de Hohenheim en créant des versions plus petites qui permettent aux agriculteurs de tester et d’évaluer la technologie à moindre frais. Malgré les résultats positifs enregistrés, les prix plus élevés des produits séchés obligeront à lancer une campagne de marketing afin de toucher des consommateurs finaux plus riches et de fournir des revenus plus élevés aux agriculteurs. En savoir plus…
Transformation du café avec des séchoirs solaires au Pérou
Energising Development Peru promotes solar dryers among smallholder coffee farmers for the first drying period, where the humidity of the beans is reduced to around 25 percent. The dryer filters UV radiation and reduces the relative humidity of the air with constant and natural ventilation. As coffee can only be stored and exported at a lower level of humidity, a second drying phase is required to get the beans down to 12 percent humidity. For this, a second solar dryer is employed which has a capacity of 2 tonnes of coffee and is managed by farmers’ associations. The implementation of this solar dryer also provided by EnDev has increased farmers’ incomes by up to 30 percent per year. Read more…
Séchage de l’origan avec des séchoirs solaires au Pérou
In Peru, in Candarave, oregano has been dried traditionally for many years. However, the residents have tried to improve their improvised driers without success. After adapting the coffee dryer (see above) to the needs of the product in order to keep its characteristic green colour despite the drying process (adjustment of level of solar radiation, degree of hydration, positioning and air flow), the quality of the product has increased notably, meeting export standards and reaching a larger market. This showcases the broad versatility EnDev’s solar dryer has, allowing its use for many different product types, reaching from fruits as pineapples and bananas to vegetables and tubers as potatoes. Read more…
Séchage des pêches avec des séchoirs solaires en Bolivie
Especially countries with a high variety of agricultural products can profit from the adaptability of the solar dryer. Another implementation example of EnDev’s solar dryer can be found in rural Bolivia, a country with a high geographical diversity, where one third of the population relies on agriculture for their main livelihood. EnDev supports two kinds of dryers: one is completely delivered by the manufacturer and costs USD 150, the other much simpler version can be constructed by the farmer using local materials such as wood and bamboo, which also encourages the technical understanding and keeps maintenance costs low. The association AFRUCH dries fruits to make them more durable. Peaches, for example, are dried for conservation and preparation of the traditional soft drink “mocochinchi”, which consists of dried peaches boiled with cinnamon and clove. After the acquisition of the solar dryer, the association could increase their income by 60 percent over the last three years. Read more…
Séchage des piments avec des séchoirs solaires au Pérou
An example of how solar dryers can be adapted to the producers’ needs could be found in Inclán, Peru, where the development of the dryer took place as a participatory process. Involving the farmers, who provided the necessary information about the product requirements, and the technical provider, which offered assistance and helped to modify the technology, the solar dryer for chili drying was developed. The main advantages were the reduced contamination of the product, which normally is dried on the ground, guaranteeing a uniform product quality, and saving enormous amounts of time. This allowed the product to enter a quality certification process and to become part of other food value chains, where the purity and adequate management of the product were required. Allowing the product to reach a higher position in the markets, the solar dryer helped generating a higher economic benefit for the Peruvian farmers of Inclán. Read more…
Études de cas sur des approches de financement de systèmes de transformation agroalimentaire à énergie solaire
Les conseils techniques et l’accès au financement sont des étapes cruciales pour garantir la mise en œuvre réussie des technologies de transformation agroalimentaire à énergie solaire. Voici un exemple qui montre comment des entreprises agroalimentaires peuvent améliorer leurs revenus en accédant à l’électricité solaire pour alimenter leurs processus de transformation :
Smart Grid on Main Street: Electricity and Value-Added Processing for Agricultural Goods (électricité et transformation à valeur ajoutée de produits agricoles
Most of Haiti’s population lack access to electricity and farmers often lose value of their crops due to missing infrastructure and processing equipment. The existing processing facilities are typically diesel-powered and expensive to operate, limiting farmers’ options to maximize the value of their products by processing agricultural goods. EarthSpark, a U.S.-based, non-profit organization with the mission of bringing energy access to Haiti’s unelectrified population, has developed a solar-diesel hybrid micro-grid system that will increase access to affordable, reliable electricity for value adding agricultural processing. Providing technical guidance and facilitating access to financing for local partners, EarthSPark assists agribusinesses in upgrading to efficient electric mills so the processing of breadfruit crops can be modernized. Using a pre-paid smart metering system, the project will also provide access to electricity to surrounding residents and boost agribusiness incomes. By the end of March 2017, EarthSpark had expanded the microgrid from a pilot stage with 54 connections to a town-sized, solar-powered smart grid providing power to residents and commercial clients through a total of 452 connections. Read more…
Publications et outils
Cette section présente une série de publications et d’outils actuels sur les technologies à énergie solaire dans les chaînes de valeur agricoles. Elle comprend des manuels, des rapports, des guides et des boîtes à outils qui permettent de visualiser les étapes préalables à la mise en œuvre.
Publications et outils sur l’énergie solaire
Global Solar Atlas
Understanding solar resource is crucial for the development of solar energy applications. The World Bank Group have provided the Global Solar Atlas in addition to a series of global, regional and country GIS data layers and poster maps, to support the scale-up of solar power in our client countries. This work is funded by the Energy Sector Management Assistance Program (ESMAP), and is part of the initiative on Renewable Energy Resource and provides long-term averages of solar resource (global, diffuse and direct normal), the principal climate phenomena that determines solar power generation. In this Global Solar Atlas, the most reliable sources of data currently available are used to generate the solar resource estimates provided, with the objective of supporting policy development and the initial decisions along the journey of developing of solar power project. Read more…
How Access to Energy can Influence Food Losses
The FAO Report “How Access to Energy can Influence Food Losses” highlights the crucial interlinkages between access to energy and food losses in developing countries. It identifies the main stages of the food value chain where increasing access to energy can play a dominant role in reducing food losses directly, by making food processing possible, as well as indirectly by acting as the main enabling factor affecting the rate at which cooling technologies are adopted. It outlines low cost and off-grid post-harvest technologies such as cooling and solar drying that can be made available in developing countries. Most importantly, it assesses the technical and economic feasibility since access to capital can be a significant barrier hindering its implementation in the Global South.Read more...
Publications et outils sur l’irrigation à énergie solaire
Les premières pompes à énergie solaire ont vu le jour à la fin des années 1970. Ce n’est toutefois que récemment que la baisse des prix des panneaux solaires a permis de développer l’utilisation de cette solution d’énergie propre de plus en plus abordable. Ses avantages pour les régions qui n’ont pas accès à l’électricité ont été prouvés, ce qui a conduit à la réalisation d’analyses en vue de leur expansion et leur développement à grande échelle dans le but d’améliorer les moyens de subsistance.
The Benefits and Risks of Solar-Powered Irrigation: An Overview
In 2015, the FAO and GIZ hosted an exploratory workshop to identify the benefits and risks of SPIS in developing countries. Representatives from regions around the globe shared their experiences and knowledge, covering a broad band of climate zones, farming systems and water usages. The results can be found in the report ‘The Benefits and Risks of Solar-Powered Irrigation: An Overview’, where the advantages of SPIS, but also the challenges of implementing this clean energy solution are collected from past experiences, allowing projections for the future. Read more…
A Field Guide to Improve Water use Efficiency in Small-Scale Agriculture: The Case of Burkina Faso, Morocco and Uganda
The Land and Water Division of FAO (CBL) and Mediterranean Agronomic Institute of Bari (CIHEAM IAM) have developed practical measures to improve water use efficiency in small-scale agriculture based on case studies from Burkina Faso, Morocco and Uganda. However, the presented combination of water use efficiency measures should remain flexible since farm conditions are commonly rather unique than universal. The Report focuses on the following areas of improvement:
- Inspection of the hydraulic structures owned and/or operated.
- Operation and maintenance of the irrigation systems and the hydraulic structures.
- Irrigation water monitoring and quantification of the available water resources.
- Adjustment of irrigation schedule to the assessed water requirement.
- Water use efficiency measures have direct impact on yield and on-farm economics through improved productivity, thus, generated income. In addition, quality of output increases as well as more efficient time management. In Africa, the irrigation potential is massively unexploited as only 5.8 percent of the cultivated lands are irrigated. The irrigation systems mostly rely on surface water, and only 19.2 percent of the lands are irrigated by groundwater. The Field Guide is addressed to agriculture practitioners and researchers. It provides a step-by-step approach in its´strive to reach optimal irrigation practices. Read more...
Solar Water Pump Outlook 2019: Global Trends and Market Opportunities
This report offers insights on the solar water pump market in six countries in sub-Saharan Africa- Côte d'Ivoire, Ethiopia, Kenya, Nigeria, Sierra Leone and Uganda- as well as India. It identifies key trends and barriers shaping the market across the areas of technology, customer demand, emerging business models and policy. Additionally, it provides recommendations on how to accelerate growth. The focus is on solar pumps designed for small-scale use. Advances in solar technology brings down costs and makes solar water pumps more accessible to small-scale farmers. Although solar currently offer lower lifetime costs, upfront costs are still higher than diesel. This aligned with limited awareness regarding subsidies and other financing opportunities, is one of the reasons why the market remains vastly unpenetrated. Coordination amongst stakeholders and between different value chain actors is seen as crucial, as well as creating a favourable policy environment and expanding research. Read more...
SPIS Toolbox
Many factors determine the type of irrigation method and respective pumping system that suits an agricultural production system best. There are many possible ways of irrigating, which have certain advantages and disadvantages for each use in agriculture. The Toolbox on Solar Powered Irrigation Systems (SPIS) can help determining which method suits best which agricultural system. It includes tools for calculation of the crop water requirements, for irrigation scheduling, but also helps setting up the SPIS, making a financing plan and determining the payback time when investing, including even a maintenance guide based on useful checklists for a longer product lifetime. Once the system requirements are determined, the appropriate technologies can be incorporated and help increasing agricultural yields.
Solar-Powered Irrigation Systems – Technology, Economy, Impacts
Irrigation is essential for productive agriculture, driving productivity and protection yields from drought. However, many farmers still use either manual methods for irrigation or expensive diesel-powered water pumps. Solar-powered irrigation promises to ensure both efficient irrigation and productivity while being environmentally friendly. The report “Solar Powered Irrigation Systems (SPIS). Technology, Economy, Impacts” gives a comprehensive overview on the technology. The report examines different irrigation technologies, explains technical characteristics and the design of the system, illustrates maintenance and management requirements, investigates both its financial viability as well as its ecological impacts and offers a comparison of different tools available for designing and managing systems. Finally, the report dives deep by examining the potentials of SPIS in four country case studies, and discussing opportunities and barriers for distribution of SPIS, such as a lack of micro-credits for farmers interested in the technology. Read more ...
Solar Irrigation Potential (SIP)
SIP is an interactive online tool to assess land suitability for irrigation using solar energy. The tool supports the user in identifying suitable areas for solar based irrigation depending on the water sources and pump characteristics. Using a suite of national and international databases to source data including solar irradiation, groundwater levels, aquifer productivity, groundwater storage, groundwater irrigation potential, proximity to rivers, proximity to reservoirs and wetlands, crop and land suitability, roads and travel time to markets, which are combined using a GIS-based Multi-Criteria Evaluation (MCE) technique to give the solar suitability ranking for a selected area. Read more...
