The National Grid Figure 2.7 shows a familiar sight the world over – the high-voltage transmission lines of an electrical grid. In a small country like Malaysia, the grid is national in scope. A National Grid is a system of electrical cables strung up high above the ground on steel pylons. In principle, the grid connects all the power stations in a small country in that each station feeds the electrical energy it generates into the grid. In this way, engineers can direct electrical power to where it is needed most. Each urban centre essentially draws power from the grid and not from individual generating stations.
Figure 2.7: Transmission Lines of the National Grid Source: farm1.static.flickr.com
In Malaysia, the typical voltages that can be found on the grid are 66, 132, 264 and 396 kilovolts. (I kilovolt = 1000 volts.) Scientists and engineers understand the need for these high – albeit dangerous – voltages. Without them, much of the electrical energy generated in our power stations at great cost will simply be wasted as heat in the transmission cables.
Solar Energy The ancient Greek name for the sun is Sol from which the term solar is derived. Solar energy thus refers to the energy we receive from the sun.
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