Fusion happens when two (or more) nuclei come close enough for the strong nuclear force to exceed the electrostatic force and pull them together. This process takes light nuclei and forms a heavier on ...
In India, water wheels and watermills were built; in Imperial Rome, water powered mills produced flour from grain, and were also used for sawing timber and stone; in China, watermills were widely used ...
Main articles: Photovoltaics and PV systemA solar cell, or photovoltaic cell (PV), is a device that converts light into electric current using the photovoltaic effect. The first solar cell was constru ...
Wind energy penetration refers to the fraction of energy produced by wind compared with the total available generation capacity. There is no generally accepted maximum level of wind penetration. The l ...
Wind power has been used as long as humans have put sails into the wind. For more than two millennia wind-powered machines have ground grain and pumped water. Wind power was widely available and not c ...
20th century, demand for electricity led to the consideration of geothermal power as a generating source. Prince Piero Ginori Conti tested the first geothermal power generator on 4 July 1904 in Larder ...
Historically, humans have harnessed biomass-derived energy since the time when people began burning wood to make fire. Even in today's modern era, biomass is the only source of fuel for domestic use i ...
Historically there has been a close correlation between economic growth and environmental degradation: as communities grow, so the environment declines. This trend is clearly demonstrated on graphs of ...
The word sustainability is derived from the Latin sustinere (tenere, to hold; sub, up). Sustain can mean “maintain", "support", or "endure”. Since the 1980s sustainability has been used more in the ...
The steady state economy is an entirely physical concept. Any non-physical components of an economy (e.g., knowledge) can grow indefinitely. But the physical components (e.g. supplies of natural resou ...
The analysis of the ownership and control of the means of production, as well as the level of their technological sophistication, is a central component of Marxist theory.In Marxist theory, the proces ...
Fundamentally, price systems have been around as long as there has been trade or money.The price system has evolved into the system of global capitalism that is present in the early 21st century. The ...
Prior to the 18th century, English-speakers generally used the word "property" in reference to land ownership. In England, "property" did not have a legal definition until the 17th century.The issue o ...
Scarcity is the fundamental economic assumption of having seemingly unlimited human needs and wants in a world of limited resources. Society has insufficient productive resources to fulfill all human ...
A primary objective of ecological economics (EE) is to ground economic thinking and practice in physical reality, especially in the laws of physics (particularly the laws of thermodynamics) and in kno ...
