Green technologies

Environmental technology (envirotech), green technology (greentech) or clean technology (cleantech) is the application of one or more of environmental science, green chemistry, environmental monitoring and electronic devices to monitor, model and conserve the natural environment and resources, and to curb the negative impacts of human involvement. The term is also used to describe sustainable energy generation technologies such as photovoltaics, wind turbines, bioreactors, etc. Sustainable development is the core of environmental technologies. The term environmental technologies is also used to describe a class of electronic devices that can promote sustainable management of resources.

Renewable energy is the energy that can be replenished easily. For years we have been using sources like wood, sun, water, etc. for means for producing energy. Energy that can be produced by natural objects like wood, sun, wind, etc. is considered to be renewable.

Water purification: The whole idea/concept of having dirt/germ/pollution free water flowing throughout the environment. Many other phenomena lead from this concept of purification of water. Water pollution is the main enemy of this concept, and various campaigns and activists have been organized around the world to help purify water.

Air purification: Basic and common green plants can be grown indoors to keep air fresh because all plants remove CO₂ and convert it into oxygen. The best examples are: Dypsis lutescens, Sansevieria trifasciata, and Epipremnum aureum.

Sewage treatment is conceptually similar to water purification. Sewage treatments are very important as they purify water per levels of its pollution. The most polluted water is not used for anything, and the least polluted water is supplied to places where water is used affluently. It may lead to various other concepts of environmental protection, sustainability etc.

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Wikipedia