Energy & Green Tech

New Zealand startup eyes global wireless electrical grid

A startup energy company in New Zealand believes it can power the world with a wireless electric transmission system that can bring power to hard-to-reach areas and do so at lower cost than with traditional power lines.

Energy & Green Tech

Decades-old mystery of lithium-ion battery storage solved

For years, researchers have aimed to learn more about a group of metal oxides that show promise as key materials for the next generation of lithium-ion batteries because of their mysterious ability to store significantly ...

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.

Engineering

New hybrid device can both capture and store solar energy

Researchers from the University of Houston have reported a new device that can both efficiently capture solar energy and store it until it is needed, offering promise for applications ranging from power generation to distillation ...

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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