Energy transition

Energy transition is generally defined as a long-term structural change in energy systems. These have occurred in the past, and still occur worldwide. Historic energy transitions are most broadly described by Vaclav Smil. Contemporary energy transitions differ in terms of motivation and objectives, drivers and governance. The layout of the world’s energy systems has changed significantly over time. Until the 1950s, the economic mechanism behind energy systems was local rather than global. As development progressed, different national systems became more and more integrated becoming the large, international systems seen today. Historical transition rates of energy systems have been extensively studied. While historical energy transitions were generally protracted affairs, unfolding over many decades, this does not necessarily hold true for the present energy transition, which is unfolding under very different policy and technological conditions. Solving the global warming problem is regarded as the most important challenge facing humankind in the 21st century. The capacity of the earth system to absorb greenhouse gas emissions is already exhausted, and under the Paris climate agreement, emissions must cease by 2040 or 2050. Barring a breakthrough in carbon sequestration technologies, this requires an energy transition away from fossil fuels such as oil, natural gas, lignite, and coal. This energy transition is also known as the decarbonization of the energy system. Available technologies are nuclear power (fission) and the renewable energy sources wind, hydropower, solar power, geothermal, and marine energy. A timely implementation of the energy transition requires multiple approaches in parallel. Energy conservation and improvements in energy efficiency thus play a major role. Smart electric meters can schedule energy consumption for times when electricity is abundant, reducing consumption at times when the more variable renewable energy sources are scarce (night time and lack of wind). Despite the widespread understanding that a transition to renewable energy is necessary, there are a number of risks and barriers to making renewable energy more appealing than conventional energy. Renewable energy rarely comes up as a solution beyond combating climate change, but has wider implications for food security and employment. This further supports the recognized dearth of research for clean energy innovations, which may lead to quicker transitions. Overall, the transition to renewable energy requires a shift among governments, business, and the public. Altering public bias may mitigate the risk of subsequent administrations de-transitioning - through perhaps public awareness campaigns or carbon levies. After a transitional period, renewable energy production is expected to make up most of the world's energy production. The risk management firm, DNV GL, forecasts that, by 2050, the world's primary energy mix will be split equally between fossil and non-fossil sources. A 2011 projection by the International Energy Agency expects solar PV to supply more than half of the world's electricity by 2060, dramatically reducing the emissions of greenhouse gases. An example of transition toward sustainable energy, is the shift by Germany (German: Energiewende) and Switzerland, to decentralised renewable energy, and energy efficiency. Although so far these shifts have been replacing nuclear energy, their declared goal 2012 was the abolishment of coal, reducing non-renewable energy sources and the creation of an energy system based on 60% renewable energy by 2050. As of 2018, the 2030 coalition goals are to achieve 65% renewables in electricity production until 2030 in Germany.