Solar Technologies Solar energy has been used for centuries for drying crops, clothes, wood, and crop residues, and heating buildings. But now methods have been developed to make these activities more efficient, and to use solar energy in different ways. There are two main types of solar energy technology: passive solar (heat) and photovoltaic. Selected examples of both are demonstrated at the site. Solar drier This is a method for increasing the efficiency and cleanliness of solar drying.
Fruit and vegetables are dried on racks in a small chamber with a solid earth back wall and plastic film covering. The drier is constructed from available stone, mud, bamboo and white plastic sheet and built facing south to maximise the sunshine it receives. The design ensures a constant airflow. Solar cooker The solar parabolic cooker is a reflecting surface in the form of a parabolic dish which concentrates the solar rays at a focal point on which the cooking pot is placed. The reflector is mounted in such a way that it can be easily adjusted to face the sun.
The quantity of heat delivered to the cooking pot is proportionate to the reflector size; very high temperatures can be attained sufficient for most conventional cooking such as rice and lentil soup (dal). The net power of the cooker is approximately 700 watts in good sunshine. Solar lamp The Tukimara solar lamp consists of a small solar photovoltaic module and three tiny semiconductor devices called white light emitting diodes (WLEDs) that convert electricity into white light more efficiently than traditional filament lamps. The three WLEDs together use only about 0. Watt of power, much less than the approximately 10 Watt consumption of the conventional solar DC lamps used in Nepal. Solar lamps have strong advantages for rural kitchens, where they provide bright, smoke-free light, with no danger of fire, unlike kerosene lamps. Solar lamps can be used like a torch, and are safe when handled by children. Development of lights using WLEDs has great potential and a big scope for mass use in low cost home lighting systems in rural areas in the Himalayan region. Solaqua solar still The Solaqua Solar Still uses natural evaporation and condensation to give pure water using solar energy.
It removes impurities such as salts, heavy metals, arsenic, and nitrates, and eliminates microbiological organisms and the taste and odour of chlorine to give pure water. This simple technology is appropriate for mountain communities and can be used under harsh mountain conditions. The equipment can produce 6 litres of purified water per day under sunny conditions. The advantages are the very simple operation and maintenance and cost effectiveness, since only solar energy is required. It is suitable for both rural and urban areas. Solar oven Cooks 3 to 4 items in 2 hours (enough for a family of 3-4) * Can be used in all seasons when there is adequate sunshine * Reduces the consumption of fuel wood * Reduces the drudgery of firewood collection (usually done by women) * Helps to save the forest and environment * Is an efficient use of solar energy Solar dryer * Can dry 6-8 kgs of food in 2 days (depending on thickness and water content) * Saves about 40% of drying time compared to in the open * Keeps food clean during the drying process and reduces unhygienic exposure to dust, insects, birds, and others * Can easily be moved to optimise exposure to the sun Is an efficient use of solar energy Solar water disinfecting device (SWAD) Disease-causing organisms in water are killed by exposure to heat in a process called pasteurisation. Water that has been heated to 65? C (150? F) for a short period of time is free from most common harmful microbes and is safe to drink. * Can be used to disinfect 6-12 litres of water per day * Helps to reduce consumption of fuel wood, exposure to smoke from burning wood, and the drudgery of collecting wood. * Is an efficient use of solar energy. Animal Husbandry
Goat husbandry Goats are part of the farm house hold in mountain farming systems. Particularly for marginal farmers, they have significant advantages over cows and buffalo. They are docile, clean and friendly animals; they require smaller capital investment, which also means less risk per animal; and they multiply faster and require less feed than the larger animals. Goats can be bred for milk or meat. Dairy goats can produce I-2 litres of milk per day; the milk has smaller particles of fat and protein than cow or buffalo milk and so is easily digestible.
It is recommended for drinking by infants and the elderly, and especially for those who have difficulty digesting cow’s milk. Goat’s milk can help build resistance to gastro-intestinal and respiratory disorders. Goat meat does not have inter-muscular fat and is recommended for consumption by people with cardiovascular diseases like high blood pressure and heart disease. Local goat breeds are less productive than improved breeds, but they are hardy and suited to local conditions. The Godavari trials are aimed at crossing to optimise improvements in goat performance whilst retaining the benefits of local breeds.
They also focus on stall feeding methods as a way of supporting natural vegetation regeneration, since goats are acute grazers if left to roam. Two pairs of pure-bred Nubian and Boer goats have been obtained from the Asian Rural Life Development Foundation (ARLDF) in the Philippines. Nubians are goats bred for milk production, yielding about two litres of milk per day. The Boer is an improved goat bred primarily for meat; a mature ram can weigh from 110-135 kg (240-300 lbs) and a ewe from 90-100 kg (200-225 lbs).
The pure bred goats have been crossed with the local breed to obtain the optimum level of performance plus hardiness for the conditions in the HKH mid hills. The male goats are used to service the goats of local farmers, with nearly 1400 offspring produced as a result so far. The aim is to demonstrate how optimising breeds can improve income and other benefits with little outlay. Angora rabbits Angora rabbits produce a high quality wool which is soft, silky, light, and warm and has a good market. They thrive in temperate climates, and can survive well at temperatures from -2? C to 35?
C, with the ideal range from 15-25? C. These rabbits are mainly bred for their wool, but after three years they can be culled and used for meat and their pelt. The paws and tails are often made into trinkets. In recent years, farmers in the HKH region have become interested in keeping Angora rabbits as an easy and relatively low cost way of generating income. A number of breeding pairs of German Angora rabbits are maintained at Godavari to demonstrate the ease and advantages of keeping these rabbits. The German Angora rabbit is a high wool producing breed; individuals weigh around 3-4 kg and produce 0. 6-1. kg of wool per year. The offspring of the rabbits are provided and sold to farmers and organisations in Nepal and Pakistan and others, close to 90 breeding pairs have been distributed so far. Soil Management The soil management activities at the Godavari site focus on various methods for reducing erosion and improving soil fertility that do not require large inputs, are not based on the use of inorganic fertiliser, and can be used by individual farmers with few resources. The major practices are described below. * Conservation Farming * Agroforestry * SALT * Green Manure * Shelter/Protection Belts * Composting