Want to stay on top of all the space news? Follow @universetoday on Twitter
Renewable energy is becoming an increasingly important issue in today’s world. There has been a demand for renewable sources of energy because they do not emit greenhouse gases – with the exception of biomass sources of energy. Main types of renewable energy include biomass, hydroelectricity, solar, wind, and geothermal.
The most widely used form of renewable energy is biomass. Biomass simply means using organic materials and converting them into other forms of energy we can use. This includes activities such as burning wood. Although some forms of biomass have been used for centuries, others are much newer. Biofuels are fuels created from biomass – organic matter. These include the widely known ethanol and biodiesel as well as newer and more experimental substances.
Many people have turned to using solar energy to provide electricity for their homes. This is done by installing photovoltaic (PV) panels on top of houses. The material used in PV panels absorbs sunlight and harnesses the electrons to generate electricity.
Wind power has been used for thousands of years as many cultures built windmills to move water or grind grain. Currently, the United States produces more wind power than any other country, although Denmark uses wind to produce a higher percent of its electricity than any other country. Approximately, 20% of Denmark’s electricity is produced using wind turbines. Some sites are better suited than others to set up wind turbines.
Geothermal energy is used extensively in Iceland. Unfortunately, since it relies on naturally occurring streams and hot springs, it is difficult to find sites to use in certain parts of the world. Geothermal energy is used to generate electricity as well as heat buildings. Geothermal energy is relatively inexpensive and is very reliable. In certain areas, such as Iceland and other countries with high levels of geothermal activity, geothermal plants have been built.
One problem with many forms of renewable energy is that they depend on circumstances of nature – wind, water supply, and sufficient sunlight for example. Another issue is the relative expense of many forms of alternate energy compared to traditional sources such as oil and natural gas. Scientists are working on improving in both of these areas in order to find alternatives to oil and natural gas.
Universe Today has articles on alternate energy and solar electricity.
Astronomy Cast has an episode on Earth.