The Annual Nile River Flood
Ancient Egyptians celebrated the arrival of the yearly flood which occurred from June to August, as they believed it was the gift of tears from the god Isis, rather than a disaster. They would use the area which annually flooded as farmland for their crops. Every year the banks of the Nile would overflow and when the water receded, a thick layer of silt rich in nutrients was left behind to renew the soil. This flood cycle was so predictable that they even based their calendar on it. It became a crucial factor in their rhythm of life, as they were a civilization strongly based on agriculture.
– Energy From Movement of Water –
1. Tidal Barrages: a similar system to hydroelectric dams, except it is built across an estuary or bay, channelling the rise and fall of ocean tides through the dam. The water flow turns turbines which in turn, serve to generate electricity. The use of large water gates allow ships to still pass through the barrier.
2. Tidal Reef: A project was proposed in Britain, the design is similar to the tidal barrage except it does not block out natural ecologies such as fish and other marine life. It would be built up in a series of sections, some of which are open to give passage to shipping. It would affect the tides less severely and have a smaller environmental impact while being able to generate energy for longer periods of time.
3. Hydro-kinetic Energy Transfer System: Another hydro-energy alternative proposed by NASA which utilizes the movement of water to produce a high-pressure liquid which can then be transferred through a flexible tube system to an onshore power plant . This method involves using the differences in temperature to create energy. The high-pressure is used to generate electricity.
– Energy From Geothermal Phenomena –
1. Geysers: Generally located near volcanic rock or ‘magma’ which heats the water until it converts into steam, geysers are a fairly rare phenomenon occurring in certain places in the world. Studies and experiments have shown that the steam produced can be manipulated into creating energy through a process which involves filtering out the rock particles, channelling the steam through turbines generators, and then bringing it into a condenser unit where it undergoes a phase change back into water (as shown in the diagram below).
2. Volcanoes: using a similar method to that of geyser-energy, volcanic energy is produced from the steam heated by the magma and used to run turbines in geothermal plants. Although it is difficult to access the source of this energy because it requires a great amount of drilling into the earth’s crust in hazardous volcanic zones, volcanic energy is used as a significant power source in many different countries such as New Zealand – covering 10% of the total energy consumption, the Philippines – 18%, and in Iceland around 25% – so much that they planned to export volcanic energy in hopes of boosting the economy.
3. “Exploding Lakes”: Lake Kivu, Rwanda, is one of the 3 known ‘killer’ or ‘exploding lakes’ in the world. This term comes from the collecting of volcanic gases near the bottom of the lake, which suddenly releases of CO2 into the air, triggered by unknown events. In the 1980’s, this phenomenon produced a cloud of CO2 which settled in the surrounding valley, killing around 1700 people. Today the government’s Kibuye power plant, which is an offshore barge, extracts methane from the depths of the lake and pumps it to the shore where it is used to power 3 generators. It currently only supplies 4% of Rwanda’s energy needs, although they plan to increase production to 10x as much within the next few years.