Energy & Green Tech

Future energy systems need to be climate proof

Climate policy for future energy systems typically focus on the challenge to make them carbon neutral to avoid climate change. However, it will also be critically important to make them climate proof to ensure that they are ...

Energy & Green Tech

Grid coordination opens road for electric vehicle flexibility

As electric vehicle (EV) sales continue to rev up in the United States, the power grid is in parallel contending with the greatest transformation in its 100-year history: the large-scale integration of renewable energy and ...

Energy & Green Tech

Open source for a global 'energiewende'

Computer models are essential for achieving energy turnaround also known as "Energiewende". Simulations can help in the planning of capacities for generating, transporting, and storing energy, taking into account dynamic ...

Electronics & Semiconductors

Researchers develop eco-friendly color thin-film solar cells

Research on solar cells to secure renewable energy sources are ongoing around the world. The Electronics and Telecommunications Research Institute (ETRI) in South Korea succeeded in developing eco-friendly color Cu(In,Ga)Se2 ...

Energy & Green Tech

Researchers harness wind data to help meet energy needs in Florida

Florida is one of several states in the Southeast where wind energy is virtually nonexistent, which is one reason wind farms have not been an economically viable energy source in the region. But a new study from the FAMU-FSU ...

Energy & Green Tech

Thermal storage units that repair themselves

In the future, paraffin wax could help to make underground thermal storage units more durable. Such systems are used, for example, to store solar energy over a longer period of time. In a new study, geologists from Martin ...

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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