electricity

Environmental System

1. Abstract In 2001, The State of Environment report clearly shows the buildings add negative impact to our natural environment up to 32% of the world’s resources, including 12% of the fresh water and up to 40% of the world’s energy. Buildings also generate 40% of waste to landfill and...

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Power Factor

The power factor of an AC electric power system is defined as the ratio of the real power to the apparent power, and is a number between 0 and 1 (frequently expressed as a percentage, e.g. 0.5 pf = 50% pf). Real power is the capacity of the circuit for...

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Solar Power II

Solar cells today are mostly made of silicon, one of the most common elements on Earth. The crystalline silicon solar cell was one of the first types to be developed and it is still the most common type in use today. They do not pollute the atmosphere and they leave...

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