Many rural villagers in Peru still lack access to running water, electricity and other amenities that we consider essential for everyday life. Some organizations are working to provide renewable energy-based technologies to bring 21st century necessities to these isolated people.
We visited the Catholic University in Lima, whose engineering department demonstrates these simple technologies in their ecological park. Displays provide options for rural people to view and consider for their own uses.
At the park entry stands the ecology house, an earthquake-proof model home built of clay and insulated with straw, both readily available materials. It has a skylight oriented for maximum light input without adding more heat to the building and vents through which hot air escapes. PV panels on the roof provide off-grid electricity, a necessity in distant villages. With 5.5 hours of usable sunlight daily, the panels provide enough power for lights, communication and refrigeration.
Clean water for drinking and water for irrigation are essential. Several simple technologies for obtaining and moving water are displayed in the park. A Midwest-type windmill and a pump constructed from two oil drums both pump water from the ground. A teeter-totter pumps water to higher elevations. Several hand-run wheels similar to those used in grist mills lift water to irrigation ditches.
The need for fuel is minimized by solar cooking options. A simple box cooker with reflecting panels is displayed. A higher-tech, German-designed solar cooker overcomes the major drawbacks of solar cookinghow to cook after the sun has set and how to control cooking heat. Collecting panels heat oil, which surrounds two large cooking kettles. The amount of heat distributed to the kettles is regulated by valves. Softball-sized rocks are added to the oil to stabilize temperatures for evening cooking. A simpler Peruvian design is also available. All solar cookers are large enough for village use.
A baking oven also minimizes the amount of fuel needed. An oil drum is set into a heavy oven built of local clay, which is dried like adobe brick. Only a small handful of twigs produce enough heat to bake the villages bread. The ovens thick walls provide insulation to maintain even temperatures.
The need for high-quality protein and fertilizer as a byproduct are provided by easy-to-raise guinea pigs. They are kept in a sheltered enclosure of clay with high sloping sides and fed readily available small grain. Their manure is used to replenish garden soil that has been depleted of nutrients by years of overuse.
Each village will customarily have a cow. Its manure is placed in an oil drum, where it decomposes to provide more fertilizer. Waste water is drawn from the drums for nutritious garden irrigation.
Polluted water is purified by native ornamental grasses planted in a switch-back ditch. As water flows from input to output, grasses remove impurities. Murky water becomes crystal clear.
We were surprised and impressed by these simple technologies. They provide inexpensive, readily available ways to pump water, recycle animal wastes, cook using the sun or less wood and provide mechanical and electrical power to improve rural village life.