97% of the water on the Earth is salt water and only three percent is fresh water; slightly over two thirds of this is frozen in glaciers and polar ice caps.
Fresh water is a renewable resource, yet the world's supply of groundwater is steadily decreasing, with depletion occurring most prominently in Asia, South America and North America, although it is still unclear how much natural renewal balances this usage, and whether ecosystems are threatened.
Using sunlight to produce electricity is called solar power (Issit).
Geothermic energy is energy made by the heat under the earth’s mantle (Issit).
Humans often increase storage capacity by constructing reservoirs and decrease it by draining wetlands.
Humans often increase runoff quantities and velocities by paving areas and channelizing the stream flow.Nevertheless, over the long term the average rate of precipitation within a watershed is the upper bound for average consumption of natural surface water from that watershed.Natural surface water can be augmented by importing surface water from another watershed through a canal or pipeline.Other users have a continuous need for water, such as a power plant that requires water for cooling.To supply such a power plant with water, a surface water system only needs enough storage capacity to fill in when average stream flow is below the power plant's need.The total quantity of water available at any given time is an important consideration.Some human water users have an intermittent need for water..pass_color_to_child_links a.u-inline.u-margin-left--xs.u-margin-right--sm.u-padding-left--xs.u-padding-right--xs.u-absolute.u-absolute--center.u-width--100.u-flex-align-self--center.u-flex-justify--between.u-serif-font-main--regular.js-wf-loaded .u-serif-font-main--regular.amp-page .u-serif-font-main--regular.u-border-radius--ellipse.u-hover-bg--black-transparent.web_page .u-hover-bg--black-transparent:hover. Content Header .feed_item_answer_user.js-wf-loaded . Renewable Energies include hydrogen fuel, biomass fuel, hydropower, solar power, geothermic energy, and nuclear power.Hydrogen fuel is an amalgamation of hydrogen and oxygen which is used to produce electricity (Issit).