Mechanical Energy
Needs for Mechanical Energy
Needs for mechanical energy are often overlooked when rural energy demands are addressed by international donor organisations; one reason might be the fact that the most common applications of mechanical energy such as water-supply, agriculture, agro-processing, natural resource extraction, small scale manufacturing and mobility are often falling into the scope of programmes of other sectors such as water, agriculture, business development or transport. The energy needs, however, are real and providing mechanical energy can have highly-significant effects on income generation and poverty reduction. Mechanical power is today obtained from motorised equipment such as steam, diesel and gas engines/turbines, electrical and hydraulic motors. In spite of these technological improvements, the 2.5 billion people without access to modern energy services still depend on unimproved versions of mechanical power equipment that inefficiently use human or animal power to meet their energy needs. However, in spite of these technical challenges, motive power has remained an important driver of livelihood activities in impoverished regions of the world.
The most common needs for mechanical energy and technological options are presented in the following. Only static applications of mechanical power are covered, so applications to assist mobility are limited to lifting and crossing.
Water supply
Mechanical energy demands for water supply include pumping of drinking water, irrigation of field crops as well as livestock watering. Traditional and still widely utilized methods of water supply rely on manual lifting / carrying of water in containers.
Agriculture
The main energy needs for agricultural production occur during activities such as tillage/ploughing, harvesting, and seeding. Traditionally these activities are carried out with animal drawn tillers and hand hoes (tillage/ploughing), scythes, animal drawn mowers, and manual practices (harvesting), and hand planting (seeding).
Agro-processing
Post-harvest activity is arguably the main factor in helping farmers increase their income. Substantial time and resources are spent transporting crops to neighbouring mills if the services are not available in farmers’ own villages. Most processes can utilise energy derived from shaft power, with many alternatives for technologies powered by human, animal, water or a stationary engine. A huge demand for mechanical energy exists for milling and pressing, where typical manually-operated technologies in widespread use are hand grounds and flails. Cutting and shredding is conducted with the help of knives and saws, while winnowing bascets are used for winnowing and decorticating. Spinning with manual spins and sun drying or drying with hand-held fans are common in most developing countries.
Natural resource extraction
Small-scale mining is a labour intensive industry that often poses serious health hazards due to poor working conditions and lack of safety precautions. Artisanal and small-scale mining (ASM) may be the only livelihood opportunity for some people, or may be their source of income during the agricultural off-season. Small-scale forest harvesting has seen increased interest in recent years due to its relatively low environmental impacts. Most traditional methods of resource extraction involve hand tools, so there is significant room for some degree of mechanical power to increase efficiency and support related livelihoods. Traditional technologies for mineral resource extraction include shovels, chisels, hammers, and pick axes for drilling, crushing, and hole enlarging, while washing and grading is in most cases done by hand. The hand saw is the traditional technology for sawing in the context of timber extraction.
