Energy & Green Tech

Path to lower emissions demands a smarter grid, say researchers

Researchers at the University of Adelaide believe the global investment being made in smart metering infrastructure could fall short of fulfilling promised benefits to customers if key systems issues are not addressed.

Energy & Green Tech

New 'water batteries' stay cool under pressure

A global team of researchers and industry collaborators led by RMIT University has invented recyclable 'water batteries' that won't catch fire or explode.

Engineering

Wind-powered Dutch ship sets sail for greener future

The world's first chemical tanker ship fitted with massive rigid aluminum "sails" has left Rotterdam, its owner hoping to plot a route to bringing down the shipping industry's huge carbon footprint.

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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