Energy & Green Tech

Instant hydrogen production for powering fuel cells

Since the Industrial Revolution, the environmental impacts of energy have posed a concern. Recently, this has driven researchers to search for viable options for clean and renewable energy sources.

Engineering

Next generation of greenhouses may be fully solar powered

Many greenhouses could become energy neutral by using see-through solar panels to harvest energy—primarily from the wavelengths of light that plants don't use for photosynthesis. Those are the findings of a new modeling ...

Machine learning & AI

Artificial intelligence is becoming sustainable

A research group from Politecnico di Milano has developed a new computing circuit that can execute advanced operations, typical of neural networks for artificial intelligence, in one single operation.

Engineering

Engineering a better world using mirrors, sun and steam

Partha Dutta, a professor of electrical, computer, and systems engineering at Rensselaer Polytechnic Institute, envisions a not-so-distant future where even the most remote parts of the world would have access to clean and ...

Energy & Green Tech

France shuts oldest reactors, but nuclear power still reigns

France will start closing its oldest atomic power plant on Saturday after 43 years in operation, the first in a series of reactor shutdowns but hardly a signal the country will reduce its reliance on nuclear energy anytime ...

Energy & Green Tech

Wearable health tech gets efficiency upgrade

North Carolina State University engineers have demonstrated a flexible device that harvests the heat energy from the human body to monitor health. The device surpasses all other flexible harvesters that use body heat as the ...

Energy & Green Tech

What if half of Switzerland's rooftops produced electricity?

Researchers at EPFL are assessing Switzerland's solar power potential. Their results show that photovoltaic panels could be installed on more than half of the country's 9.6 million rooftops. The resulting power would meet ...

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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