Renewable energy is energy that is replaced as quickly as it is used. A prime example of this type of energy is solar power. Other sources of renewable energy include biomass, geothermal, hydropower, wind, and biomass. Renewables don't answer all our energy needs, but they do safeguard our environment while still generating useful energy. They account for some 25% of our energy usage worldwide and are expected to continue to gain more of a foothold as interest in renewable energy grows.
Most renewable energy technologies are either directly or indirectly fueled by the sun. The atmosphere of the Earth is a complex system in equilibrium so that incoming solar radiation is equivalent to the heat radiation traveling into space. This balance essentially creates what is known as the earth's climate. When incoming radiation reaches the earth, much of it is absorbed into the earth's water systems around the equator. The absorbed energy is transferred throughout the earth in the form of water currents and wind systems. The distribution of water around the earth's surface is what gives us the ability to harness water for hydroelectric energy, and the rays of the sun produce plants that are used in the making of biofuels. We can see that renewable energy from the sun is a driving force of most other forms of energy.
Many critics state that renewable energy alone can not provide the necessary amounts of energy that we need to survive on this planet. While this may be true based on current energy consumption, it is definitely a strong force that drives the use of alternative energies and helps our planet move away from fossil fuels. Because renewable energy may not always be available, it is also not considered a viable alternative to current energy producing methods. These critics state that the sun is not always shining, the wind is not always blowing, and other forms of renewables rely on ideal conditions to perform. While this may be true to some extent, it is definitely not a hindrance to their use.
In order to achieve mass production of electricity from renewable energy, newer technologies must be ever changing to maximize the amount of energy output. While there may be some drawbacks to renewable energy, it has been providing for the growth and sustainability of our civilizations since the dawn of our planet.