sustainability

Sustainability is a compromise. It is the ability for humans to use the earth without abusing its natural resources; improving the quality of human life while living within the carrying capacity of supporting eco-systems. Unfortunately, our earth's natural resources have greatly decreased in recent years. Water shortages, soil exhaustion, loss of forests, air and water pollution, and degradation of coastlines afflict many areas. As the world's population grows, improving living standards without destroying the environment is a global challenge. However, due to today's modern technology, scientists have founded new, renewable energy sources such as wind, sunlight, and heat.

Wind is a clean, inexhaustible, indigenous energy resource that can generate enough electricity to power millions of homes and businesses. Wind energy is one of the fastest growing forms of electricity generation in the world. The United States can currently generate more than 25,00 megawatts (MW) of electricity from the wind, which is enough to power about 7 million average American homes. Industry experts predict that, with proper development, wind energy could provide 20% of this nation's energy needs.

Solar cells convert sunlight directly into electricity. They are often used to power calculators and watches. These cells are made of semiconducting materials similar to those used in computer chips. When sunlight is absorbed by these materials, the solar energy knocks electrons loose from their atoms, allowing the electrons to flow through the material to produce electricity. This process of converting light (photons) to electricity (voltage) is called the photovoltaic (PV) effect. Solar energy technologies use the sun's energy and light to provide heat, light, hot water, electricity, and even cooling for homes, businesses, and industry. For example, thin film solar cells use layers of semiconductor materials only a few micrometers think. Thin film technologyg has made it possible for solar cells to now double as rooftop shingles, roof tiles, building facades, or glazing for skylights or atria. The solar cells version of items such as shingles offer the same prtection and durability as ordinary asphalt shingles.

Envirnomentalists and economists increasingly agree that efforts to protect the environment and to achieve better living standards can be closely linked and are mutually reinforcing. Slowing the increase in population, especially in the face of rising per capita demand for natural resources, can take pressure off the environment and buy time to improve living standards on sustainable basis.

Alyssa G
www.epa.gov/sustainability.com
www.renewableenergyworld.com