Solar Energy 7

SOLAR ENERGY

INTRODUCTION:

The radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies.   The solar-powered resources such as wind and wave power, hydroelectricity and biomass, account for most of the available renewable energy on earth.   A partial list of solar applications and disinfection, day lighting, solar hot water, solar cooking, and high temperature process heat for industrial purposes.

CONTENTS:

1. Energy from the sun

2. Applications of solar technology

    • Architecture and urban planning

    • Agriculture and horticulture

    • Solar lighting

    • Heating, Cooling and ventilation

    • Solar thermal

    • Water treatment

    • Solar Cooking

      3. Energy storing device

      4. Conclusion

ENERGY FROM THE SUN:

The Earth receives 174 petawatts (PW) of incoming solar radiation at the upper atmosphere. Approximately 30% is reflected back to space while the rest is absorbed by clouds, oceans and land masses.   Earth’s land surface, oceans and atmosphere absorb solar radiation, and this raises, causing atmospheric circulation or convection, producing atmospheric phenomena such as wind, cyclones and anti-cyclones.

Sunlight absorbed by the oceans and land masses keeps the surface at an average temperature of 14 degree Celsius.   By photosynthesis green plants convert solar energy into chemical energy, which produces food, wood and the biomass from which fossil fuels are derived.

Solar energy can be harnessed in different levels around the world.   Depending on a geographical location the closer to the equator the more “potential” solar energy is available.   The total solar energy absorbed by Earth's atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ) per year.    In 2002, this was more energy in one hour than the world used in one year. Photosynthesis captures approximately 3,000 EJ per year in biomass. ...