Why is solar energy better?
Five sustainable sources of carbon-neutral energy are currently being discussed and investigated to meet the anticipated global need of 30-45 TW. Researchers have calculated how much energy could be produced if current existing technologies were fully implemented around the globe. EARTH: If the geothermic potential of all hot springs, geysers, and other natural heat sources were tapped for energy, less than 12 TW would be generated; a much smaller fraction is actually realistic. The Earth's usable heat is not sufficient to provide the world's energy demands. WIND: If all the surface winds on the face of the Earth could be utilized, only about 12 TW could be tapped; realistically, only 2.5 TW could be generated. BIOMASS: If sugarcane or some other high yield crop were planted on all cultivatable land across the world, only 6 TW would be produced and that would leave no land to grow food crops. WATER: If all the potential hydroelectric energy available from all the water flowing downhill in all the rivers, lakes, and oceans on Earth is used, only 4-5 TW could be produced; 1.5 TW might be practically possible. SUN: The sun is a giant nuclear fusion reactor at a safe distance of about 93,000,000 miles from our planet. The energy of the sunlight that hits the surface of the Earth in one hour is equal to the current worldwide energy demand for an entire year: 15 TW in 60 minutes. Developing the infrastructure to harvest energy practically from all hydroelectric, geothermal, wind, and biomass sources would yield only 12-14 TW — only half of what is needed by 2050. Conversely, implementing solar energy technologies alone on a modest global scale would meet our needs through 2100 and beyond. |