Business

Toyota targets carbon-neutral plants by 2035

Toyota, the world's biggest automaker, said Friday it aims to make its production carbon-neutral by 2035, replacing the previous target date of 2050.

Business

Researchers build supply chain model to support hydrogen economy

Over the past decades, the need for carbon-free energy has driven increasing interest in hydrogen as an environmentally clean fuel. But shifting the economy away from fossils fuels to clean-burning hydrogen will require significant ...

Energy & Green Tech

Chile inaugurates Latin America's first thermosolar plant

Chile on Tuesday inaugurated Latin America's first-ever thermosolar energy plant, a vast complex dubbed Cerro Dominador in the Atacama desert that gives a boost to the country's quest for carbon-neutrality by 2050.

Energy & Green Tech

Saving the climate with solar fuel

Mobility analyses show: Only a small proportion of all vehicles are responsible for the majority of the kilometers driven. We are talking above all about long-distance trucks that transport goods all over Europe. If these ...

Engineering

Innovative batteries put flying cars on the horizon

Jet packs, robot maids and flying cars were all promises for the 21st century. We got mechanized, autonomous vacuum cleaners instead. Now a team of Penn State researchers are exploring the requirements for electric vertical ...

Energy & Green Tech

Capturing water to make the renewable fuels of the future

A successful outcome for the energy transition is very much dependent on the development of alternative fuel solutions that are ultra-clean, renewable, and low in carbon emissions. Fuels that must be replaced include liquefied ...

Security

Energy chief cites risk of cyberattacks crippling power grid

Energy Secretary Jennifer Granholm on Sunday called for more public-private cooperation on cyber defenses and said U.S. adversaries already are capable of using cyber intrusions to shut down the U.S. power grid.

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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