Question

can net energy be zero once? ​

Answer 1

Answer:

Zero net energy (ZNE) building, net zero energy building (NZEB), net zero building is a building with zero net energy consumption, meaning the total amount of energy used by the building on an annual basis is equal to the amount of renewable energy created on the site, or in other definitions by renewable energy sources off site. In some cases these buildings consequently contribute less overall greenhouse gas to the atmosphere during operations than similar non - ZNE buildings. They do at times consume non renewable energy and produce greenhouse gases, but at other times reduce energy consumption and greenhouse gas production elsewhere by the same amount. A similar concept approved and implemented by the European Union and other agreeing countries is nearly Zero Energy Building (NZEB), with the goal of having all buildings in the region under NZEB standards by 2020.

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