Energy & Green Tech

Ambitious but controversial: Japan's new hydrogen project

Japan's new 2050 deadline for carbon neutrality has thrown a spotlight on its efforts to find new, greener fuel options, including an ambitious but controversial liquid hydrogen venture.

Energy & Green Tech

Australia constructing giant 300-megawatt battery

Australia is poised to construct one of the world's largest batteries, using Tesla's technology for lithium-ion batteries. The football-field sized battery will provide up to 300 megawatts of power output and 450 megawatts-hours ...

Energy & Green Tech

Scientists develop energy-saving 'liquid window'

Scientists at the Nanyang Technological University, Singapore (NTU Singapore) have developed a liquid window panel that can simultaneously block the sun to regulate solar transmission, while trapping thermal heat that can ...

Electronics & Semiconductors

Boosting the capacity of supercapacitors

Carefully designed covalent organic frameworks could make supercapacitor electrodes that have a greater ability to store electric charge.

Energy & Green Tech

Solar perovskite production on a roll

High-performance perovskite solar cells are made using a manufacturing-friendly liquid-based process suitable for roll to roll production.

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Energy

In physics, energy (from the Greek ἐνέργεια - energeia, "activity, operation", from ἐνεργός - energos, "active, working") is a scalar physical quantity that describes the amount of work that can be performed by a force, an attribute of objects and systems that is subject to a conservation law. Different forms of energy include kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic energy. The forms of energy are often named after a related force.

Any form of energy can be transformed into another form, but the total energy always remains the same. This principle, the conservation of energy, was first postulated in the early 19th century, and applies to any isolated system. According to Noether's theorem, the conservation of energy is a consequence of the fact that the laws of physics do not change over time.

Although the total energy of a system does not change with time, its value may depend on the frame of reference. For example, a seated passenger in a moving airplane has zero kinetic energy relative to the airplane, but non-zero kinetic energy relative to the Earth.

This text uses material from Wikipedia, licensed under CC BY-SA