water power

Examples of water power in the following topics:

• Micro-hydro power stations

  • Micro-hydro stations use natural water fl ows from rivers and streams to produce hydroelectricity.
  • The turbines they house are small so they blend into natural settings while producing enough electricity to power several hundred homes or businesses.
  • Micro-hydro stations are particularly viable in areas where industrialists during the 18th and 19th centuries built now-unused weirs to turn water wheels that powered looms and other industrial machinery.
  • To read more about micro-hydro stations visit www.energysavingtrust.org.uk/Generate-your-own-energy/Hydroelectricity or www.absak.com/library/micro-hydro-power-systems.

• Thermal Pollution

  • Thermal pollution is the degradation of water quality by any process that changes ambient water temperature.
  • Thermal pollution is the degradation of water quality by any process that changes ambient water temperature.
  • A common cause of thermal pollution is the use of water as a coolant, for example, by power plants and industrial manufacturers.
  • Elevated water temperature typically decreases the level of dissolved oxygen of water.
  • This is a cooling tower at Gustav Knepper Power Station, Dortmund, Germany.

• Advantages of fuel cells

  • 70%–85% of the energy obtained from the fuel in a fuel cell can be converted into power and heat compared to coal or oil, which is around 35%.
  • Fuel cells are inherently reliable, rugged, quiet and versatile and they can be used to power almost anything from a hearing aid to an office building.
  • Currently, fuel cells are being developed to power cars (every major automotive manufacturer in the world now has a fuel cell vehicle in development), buses, boats, trains, planes, consumer electronics, portable power units and wastewater treatment plants (where the methane produced by the wastewater is used as a fuel source).
  • Since fuel cells are smaller than coal-fired furnaces, less land is required to set them up as compared to traditional power plants.
  • The pure water emitted as a waste product from a fuel cell can always be put to good use.

• Water Waves

  • If you blow on the surface of any body of water with enough force you can generate water waves.
  • Since water waves transport energy, attempts to generate power from them have been made by utilizing the physical motion of such waves.
  • Although larger waves are more powerful, wave power is also determined by wave speed, wavelength, and water density.
  • Deep water corresponds with a water depth larger than half the wavelength, as is a common case in the sea and ocean.
  • The deep-water group velocity is half the phase velocity.

• River Valley Civilizations

  • A hydraulic empire (also known as hydraulic despotism, or water monopoly empire) is a social or governmental structure which maintains power through exclusive control over water access.
  • Power, both over resources (food, water, energy) and a means of enforcement, such as the military, are vital for the maintenance of control.
  • Water stress is the term used to describe difficulty in finding fresh water or the depletion of available water sources.
  • Water shortage is the term used when water is less available due to climate change, pollution, or overuse.
  • Water crisis is the term used when there is not enough fresh, clean water to meet local demand.

• Purification of Drinking Water

  • Screening: Water is passed through a screen filter to remove large debris.
  • Storage: Water is stored in reservoirs, tanks, and water towers in preparation for purification.
  • Chlorine can sometimes leave residual byproducts in water.
  • Ozone is an unstable molecule that readily gives up one atom of oxygen providing a powerful oxidizing agent.
  • However, it is not as effective in cloudy water.

• Reducing the cost of pumps and pumping

  • Up to 20% of the world's motors are used for pumping purposes and most of what they pump is water.
  • Water and wastewater pumps consume over 50 billion kilowatt-hours of electricity in the USA every year (about $4 billion worth of power) and most of the energy they consume is used to fight against the friction created when water is forced through narrow pipes, around bends and up steep inclines.
  • Just as with motors, most pumps are bigger and more powerful than they need to be because in many cases production designers did not know what the exact pumping requirements were when the pumping system was being planned.

• Delegated Powers

  • The delegated powers are a list of items found in the U.S.
  • Almost all presidential powers rely on what Congress does or does not do.
  • And many presidential powers are delegated powers that Congress has accorded presidents to exercise on its behalf and that it can cut back or rescind.
  • The delegated powers, also called enumerated powers, are a list of items found in Article I, Section 8 of the U.S.
  • The list of enumerated powers includes the following: "The Congress shall have Power To lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts and provide for the common Defence and general Welfare of the United States; but all Duties, Imposts and Excises shall be uniform throughout the United States;" "To borrow Money on the credit of the United States;" "to declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;" and "to make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof."

• Phylum Echinodermata

  • The more notably distinct trait, which most echinoderms have, is their remarkable powers of regeneration of tissue, organs, limbs, and, in some cases, complete regeneration from a single limb.
  • The madreporite is a light-colored, calcerous opening used to filter water into the water vascular system of echinoderms.
  • Water enters the madreporite on the aboral side of the echinoderm.
  • The ring canal connects the radial canals (there are five in a pentaradial animal), and the radial canals move water into the ampullae, which have tube feet through which the water moves.
  • By moving water through the unique water vascular system, the echinoderm can move and force open mollusk shells during feeding.

• Boiling Point and Water Solubility

  • It is instructive to compare the boiling points and water solubility of amines with those of corresponding alcohols and ethers.
  • The dominant factor here is hydrogen bonding, and the first table below documents the powerful intermolecular attraction that results from -O-H---O- hydrogen bonding in alcohols (light blue columns).
  • The water solubility of 1º and 2º-amines is similar to that of comparable alcohols.
  • As expected, the water solubility of 3º-amines and ethers is also similar.
  • These comparisons, however, are valid only for pure compounds in neutral water.