 |
|
| News | Events | Sites | Database | Knowledge Base | Forum |
|
FACTS AND FIGURES ABOUT WATER AND ENERGY Since the Rio Earth Summit in 1992, the crucial role of energy as a component in sustainable development has been widely recognized. Although Agenda 21 did not have a chapter specifically devoted to energy, its comprehensive programme for action to achieve sustainable patterns of production and consumption revealed how closely such aims are linked to the availability of affordable energy. The world is facing a situation in which 2 billion people have no electricity at all, and 2.5 billion people in developing countries, mainly in rural areas, have little access to commercial energy services. The world electricity consumption is expected to rise by 73% between 1999 and 2020, making electricity the fastest-growing form of energy. This growth will be driven mainly by developing countries. Water is used in most means of generating power, and in many countries hydropower is the only really sustainable energy source. Hydropower is already a major contributor to the world’s energy balance, providing 19% of total electricity production. Hydropower plants generate electricity or mechanical power by converting the power available in the flowing water of rivers, canals or streams. This requires a suitable rainfall catchment area, a hydraulic head, a means of transporting water from the intake to the turbine, such as a pipe or millrace, a power house containing the power generation equipment and a valve gear needed to regulate the water supply as well as all primary mechanical and electrical equipment components, and, finally, a tailrace to return the water to its natural course. Hydropower supplies at least 50% of electricity production in 66 countries, and at least 90% in 24 countries. About half of this capacity and generation is in Europe and North America. The provision of an adequate modern energy supply for water-related activities in rural areas of developing countries offers many advantages, including time saved not having to travel to collect water, thus increasing productivity; easier access to water through the pumping of drinking water, irrigation water and water for animal husbandry; health benefits (ranging from water purification through filtration to reduced medical costs when boiling water for sterilization is unnecessary); and health and environmental benefits through the discharge of wastewater from canals, septic tanks and latrines. Energy also allows wastewater to be treated through aeration. Hydropower generation does not consume water. Energy generation can, however, result in location-specific water problems for other users. In the Ruhuna (Sri Lanka) basins, water diverted for energy generation now returns to the river downstream from an established irrigation system. The transfer of water from agriculture has socio-political repercussions as well as economic impacts. Although the power generation authority is willing to compensate farmers for loss of water supplies, the agricultural community has so far preferred to continue irrigated cultivation. This may be due to the limited alternative to farming in the relatively remote areas of the affected villages. In addition, compensation in place of agricultural activities leeds to an increase in social and cultural problems. One farmer said: ‘But sir, we do not want to live in a dead village. When we cultivate, we work together and have ceremonies and parties. Vehicles come to bring inputs and take away our crops. Now no one comes, we just sit on the guard stones and wait.’
Information from: Source: UNESCO Water Portal, September 2005
|