Engineering

A shift in energy planning—using models in a different way

To meet the complex requirements of future building and energy systems, Empa researcher Matthias Sulzer and Berkeley Lab researcher Michael Wetter are proposing a paradigm shift in planning of such systems: They call for ...

Energy & Green Tech

Mineralizing emissions: Advanced reactor designs for CO₂ capture

In advancing sustainable waste management and CO2 sequestration, researchers have crafted reactors that mineralize carbon dioxide with fly ash particles. This avant-garde technique is set to offer a sustainable and lasting ...

Energy & Green Tech

California drives toward an electric future

The pressure is on for California to meet its clean-vehicle goals. In less than two years, 35% of vehicles sold must have zero tailpipe emissions. And by 2035, all light-duty vehicles sold must be zero-emissions.

Energy & Green Tech

Developing high-efficiency colored solar panels for buildings

The energy transition in Germany, Europe, and across the world is driving robust demand for solar panels. Alongside high energy yields, aesthetics and acceptance are also increasingly important factors. To accommodate these ...

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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