Energy & Green Tech

Using mountains for long-term energy storage

Batteries are rapidly becoming less expensive and might soon offer a cheap, short-term solution to store energy for daily energy needs. However, the long-term storage capabilities of batteries, for example, in a yearly cycle, ...

Energy & Green Tech

Speeding up the transition towards sustainable cities

In a rapidly urbanizing world, the concept of smart cities is increasingly being used across Europe to improve the quality of life for citizens. Thanks to several EU-funded projects, such as MAtchUP, Sharing Cities and REMOURBAN, ...

Energy & Green Tech

Making ceramic tile production greener with reused heat

With its wide range of applications from construction to consumer goods, industrial processes and cutting-edge technologies, the ceramics industry is an integral part of EU manufacturing. A key component of energy-intensive ...

Energy & Green Tech

Smooth and stable electric vehicle charging

Siwar Khemakhem, Mouna Rekik, and Lotfi Krichen of the Control and Energy Management Laboratory at the National Engineering School of Sfax, in Tunisia, are investigating the potential of home energy management based on plug-in ...

Energy & Green Tech

Distributed solar prices fall annually by 5% to 7%

The latest edition of Lawrence Berkeley National Laboratory's (Berkeley Lab's) annual Tracking the Sun report finds that prices for distributed solar power systems continued to fall in 2018, that industry practices continued ...

Energy & Green Tech

Idaho, Energy Department sign deal on spent nuclear fuel

Idaho granted a conditional waiver Thursday to the U.S. Department of Energy that could allow research quantities of spent nuclear fuel into the state after years of blocking such shipments.

Energy & Green Tech

How do solar panels work?

How do solar panels work? – Nathan, age 5, Melbourne, Australia.

Engineering

Breaking down controls to better control wind energy systems

Researchers based in Brazil have developed a way to better control wind energy systems in electrical generation. Wind energy systems are typically expensive to maintain, and they can only convert a portion of their produced ...

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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