Energy & Green Tech

Why we should use electric rather than hydrogen cars

Last night's Federal Budget did not have any promising signals for encouraging uptake of electric vehicles, or to increase spending on installing the essential infrastructure needed to allay fears that motorists won't be ...

Engineering

A long-lasting, stable solid-state lithium battery

Long-lasting, quick-charging batteries are essential to the expansion of the electric vehicle market, but today's lithium-ion batteries fall short of what's needed—they're too heavy, too expensive and take too long to charge.

Energy & Green Tech

Study shows renewable energy will enhance power grid's resilience

A new Dartmouth Engineering study shows that integrating renewable energy into the American Electric Power System (AEPS) would enhance the grid's resilience, meaning a highly resilient and decarbonized energy system is possible. ...

Energy & Green Tech

Renewable energy powers ahead in 2020: report

Renewable energy grew at its fastest rate in two decades, driven primarily by gains in China and wind power, the International Energy Agency said in a report Tuesday.

Security

FBI names pipeline cyberattackers as company promises return

Hit by a cyberattack, the operator of a major U.S. fuel pipeline said Monday it hopes to have services mostly restored by the end of the week as the FBI and administration officials identified the culprits as a gang of criminal ...

Energy & Green Tech

Chill out: Advanced solar tech runs cooler and lasts longer

Australian photovoltaics researchers have made a 'cool' discovery: Singlet fission and tandem solar cells—two innovative ways to generate solar power more efficiently—also help to lower operating temperatures and keep ...

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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