1,720,988 research outputs found
Energy resources: alternative energy in perspective
No full textAlternative energy sources are seen by many people as potential solutions to the many economic and environmental challenges posed by the current dominance of world energy supply by fossil and nucler fuels. Just how realistic are these hopes? This unit summarises the technical and geographic challenges posed by each alternative source. It is left to you to judge the feasiibility of imploementing these changes against the claims for 'alternative' solutions to global energy challenges that are regularly made.
Climate change
No full textHuman societies have to take urgent action to end their dependences on fossil fuels. We have to alter the whole path of our development and decision making in order to make our societies both environmentally adaptable and sustainable. This unit takes on the task of trying to chart some of the ways in which it might be possible.
Water: Surface water
No full textWater is arguably the most important physical resource as it is the one that is essential to human survival. Understanding the global water cycle and how we use water is essential to planning a sustainable source of water for the future. In the UK there area areas where water supplies are limited, shown by recent droughts. Globally, there are many areas that do not have enought water to support the currently population adequately. Decisions will have to be made on the best way to use water in a world where there is climate change. An OpenLearn Resource - Time: 8 hours & Level: Intermediate
Energy resources: hydropower
No full textHydroelectric energy is ultimately solar energy converted through evaporation of water, movement of air masses and precipitation to gravitational potential energy and then to the kinetic energy of water flowing down a slope. That energy was harnessed for centuries through the use of water wheels to drive mills, forges and textile works, before being supplanted by coal-fired steam energy. The unit considers hydropower as a potential source of useable energy.
Energy resources: tidal energy
No full textThe rise and fall of ocean tides result from the combined gravitational pull on water by the Moon and, to a lesser extent, bu the Sun, which exerts a force on water directed towards the two astronomical bodies. These gravitational effects combine with centrifugalo forces that result from the Earth and the Moon orbiting each other to make the details of tidal changes complex. This unit considers the power of the ocean tides as a potential source of useable energy and whether or not they can ever make any significant contribution to global energy suppllies.
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