Energy & Green Tech

Study measures Switzerland's potential geothermal heating capacity

An EPFL Ph.D. student has calculated the maximum amount of geothermal energy that could theoretically be extracted using ground-source heat pumps in the Cantons of Vaud and Geneva. In a study combining data on the area available ...

Electronics & Semiconductors

New semiconductor coating may pave way for future green fuels

Hydrogen gas and methanol for fuel cells, or as raw materials for the chemicals industry, for example, could be produced more sustainably using sunlight, a new Uppsala University study shows. In this study, researchers have ...

Energy & Green Tech

How to accelerate solar adoption for the underserved

As rooftop solar prices have fallen, many households at all income levels can now save money by going solar. Nonetheless, low- and moderate-income households remain less likely to adopt solar than high-income households. ...

Energy & Green Tech

Australia constructing giant 300-megawatt battery

Australia is poised to construct one of the world's largest batteries, using Tesla's technology for lithium-ion batteries. The football-field sized battery will provide up to 300 megawatts of power output and 450 megawatts-hours ...

Energy & Green Tech

Scientists develop energy-saving 'liquid window'

Scientists at the Nanyang Technological University, Singapore (NTU Singapore) have developed a liquid window panel that can simultaneously block the sun to regulate solar transmission, while trapping thermal heat that can ...

Energy & Green Tech

The influence of social norms and behaviour on energy use

People tend to conform to what others do and what others regard as right. Do these two social norms influence electric energy consumption? In the prestigious journal Nature Energy, a team of Italian scientists have identified, ...

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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