Energy & Green Tech

Can energy-efficient federated learning save the world?

Training the artificial intelligence models that underpin web search engines, power smart assistants and enable driverless cars consumes megawatts of energy and generates worrying carbon dioxide emissions. But new ways of ...

Energy & Green Tech

Vertical turbines could be the future for wind farms

The now-familiar sight of traditional propeller wind turbines could be replaced in the future with wind farms containing more compact and efficient vertical turbines. New research from Oxford Brookes University has found ...

Engineering

Sunlight to solve the world's clean water crisis

Researchers at UniSA have developed a cost-effective technique that could deliver safe drinking water to millions of vulnerable people using cheap, sustainable materials and sunlight.

Engineering

Solar-powered desalination unit shows great promise

Despite the vast amount of water on Earth, most of it is nonpotable seawater. Freshwater accounts for only about 2.5% of the total, so much of the world experiences serious water shortages.

Electronics & Semiconductors

Researchers demonstrate fully recyclable printed electronics

Engineers at Duke University have developed the world's first fully recyclable printed electronics. By demonstrating a crucial and relatively complex computer component—the transistor—created with three carbon-based inks, ...

Energy & Green Tech

US power sector is halfway to zero carbon emissions

Concerns about climate change are driving a growing number of states, utilities, and corporations to set the goal of zeroing out power-sector carbon emissions. To date 17 states plus Washington, D.C. and Puerto Rico have ...

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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