Pollution's devastating effects on the environment have become more obvious in recent years, sparking a movement to promote energy efficiency, less reliance on fossil fuels, and a reduction in air and water pollution. Most scientists agree that such changes are necessary to protect our environment from further harm.
The construction industry consumes a large quantity of energy and resources and creates a huge amount of pollution. In the United States, building and development account for 39% of the country's total energy use, 12% of total water consumption, 68% of total electricity consumption, and 38% of carbon dioxide emissions, according to the Environment Protection Agency.
Green buildings use less energy, water, create less waste, and are healthier to live, work, or go to school in than standard buildings. Contractors of green buildings incorporate techniques that use resources more efficiently during the entire building cycle—construction, renovation, operation, maintenance, and demolition—than builders of conventional structures.
The environmental benefits of building green include the protection of ecosystems and biodiversity, improved air and water quality, less waste flowing into streams, and the conservation of natural resources. Green buildings can also result in lower operating costs because they typically use less energy and materials and improved indoor air quality, which improves the health of occupants.
The process of building green includes technical and aesthetic planning with nature conservation in mind. Building designs often reflect the surrounding environment and natural resources and utilize renewable building materials such as bamboo and straw. In addition, recycled resources found locally are used for green buildings, diminishing the cost and air pollution associated with transporting materials long distances.
Careful site selection is important to minimize human impact on the surrounding environment. For example, placing a structure in an area that allows it to take advantage of cool breezes and sunlight can reduce energy use and expenses. More energy and expense are needed for larger buildings as well, so it is important to build small.
Green roofs are another feature of green houses that reduce energy use and cost. These roofs are partially or completely covered with vegetation, which helps minimize heating and cooling costs, prevent storm-water runoff, and filter pollutants.
Other features of green buildings often include energy and water conservation, recycling, and waste reduction. In addition, renewable energy sources such as solar power, hydropower, and wind power are used for heat and electricity, which significantly reduces costs and decreases the impact on the environment.
Currently, 25 cities in the United States are working to develop a sustainable city infrastructure that encourages the use of solar energy by both residents and businesses. Benefits of solar energy include obtaining power from secure domestic sources, sustainable urban development, progress toward meeting greenhouse gas emission reduction goals, and new economic opportunity. On March 28, 2008, the U.S. Department of Energy announced that it will give up to $2.4 million to the following 12 U.S. cities for solar energy advancement.