Sustainable energy in the context of "Hydropower"

Climate change mitigation (or decarbonisation) is action to limit the greenhouse gases in the atmosphere that cause climate change. Climate change mitigation actions include conserving energy and replacing fossil fuels with clean energy sources. Secondary mitigation strategies include changes to land use and removing carbon dioxide (CO₂) from the atmosphere. Recent assessments emphasize that global greenhouse gas emissions must peak before 2025 and decline by about 43% by 2030 to limit warming to 1.5 °C, requiring rapid transitions in energy, transport, and land-use systems. Current climate change mitigation policies are insufficient as they would still result in global warming of about 2.7 °C by 2100, significantly above the 2015 Paris Agreement's goal of limiting global warming to below 2 °C.

Solar energy and wind power can replace fossil fuels at the lowest cost compared to other renewable energy options. The availability of sunshine and wind is variable and can require electrical grid upgrades, such as using long-distance electricity transmission to group a range of power sources. Energy storage can also be used to even out power output, and demand management can limit power use when power generation is low. Cleanly generated electricity can usually replace fossil fuels for powering transportation, heating buildings, and running industrial processes. Certain processes are more difficult to decarbonise, such as air travel and cement production. Carbon capture and storage (CCS) can be an option to reduce net emissions in these circumstances, although fossil fuel power plants with CCS technology is currently a high-cost climate change mitigation strategy.

Green infrastructure or blue-green infrastructure refers to a network that provides the "ingredients" for solving urban and climatic challenges by building with nature. The main components of this approach include stormwater management, climate adaptation, the reduction of heat stress, increasing biodiversity, food production, better air quality, sustainable energy production, clean water, and healthy soils, as well as more human centered functions, such as increased quality of life through recreation and the provision of shade and shelter in and around towns and cities. Green infrastructure also serves to provide an ecological framework for social, economic, and environmental health of the surroundings. More recently scholars and activists have also called for green infrastructure that promotes social inclusion and equity rather than reinforcing pre-existing structures of unequal access to nature-based services.

Green infrastructure is considered a subset of "Sustainable and Resilient Infrastructure", which is defined in standards such as SuRe, the Standard for Sustainable and Resilient Infrastructure. However, green infrastructure can also mean "low-carbon infrastructure" such as renewable energy infrastructure and public transportation systems (See "low-carbon infrastructure"). Blue-green infrastructure can also be a component of "sustainable drainage systems" or "sustainable urban drainage systems" (SuDS or SUDS) designed to manage water quantity and quality, while providing improvements to biodiversity and amenity.

Energy consumption is the amount of energy used. In physics, energy consumption refers to the transformation of energy from one form to another, rather than its complete disappearance. According to the law of conservation of energy, energy cannot be created or destroyed, only converted. For instance, when a light bulb "consumes" electricity, it is not destroying the electrical energy but rather converting it into light and heat. Similarly, a car "consumes" gasoline by converting its chemical energy into kinetic energy (motion) and heat. Understanding energy consumption is crucial for analyzing the efficiency of various systems and processes, as the ultimate goal is often to minimize the conversion of useful energy into less desirable forms, such as waste heat.

From a societal and economic perspective, "energy consumption" often refers to the use of energy resources by human civilization to power homes, industries, transportation, and other activities. This typically involves drawing upon various primary energy sources, including fossil fuels (coal, oil, natural gas), nuclear power, and renewable sources (solar, wind, hydro, geothermal). The scale and patterns of this consumption have significant implications for environmental sustainability, economic development, and geopolitical stability. Analyzing trends in global and regional energy consumption helps policymakers and researchers understand resource availability, greenhouse gas emissions, and the potential for transitioning to more sustainable energy systems.

Electrification is the process of powering by electricity and, in many contexts, the introduction of such power by changing over from an earlier power source. In the context of history of technology and economic development, electrification refers to the build-out of the electricity generation and electric power distribution systems. In the context of sustainable energy, electrification refers to the build-out of super grids and smart grids with distributed energy resources (such as energy storage) to accommodate the energy transition to renewable energy and the switch of end-uses to electricity.

The electrification of particular sectors of the economy, particularly out of context, is called by modified terms such as factory electrification, household electrification, rural electrification and railway electrification. In the context of sustainable energy, terms such as transport electrification (referring to electric vehicles) or heating electrification (referring to heat pumps powered with solar photovoltaics) are used. It may also apply to changing industrial processes such as smelting, melting, separating or refining from coal or coke heating, or from chemical processes to some type of electric process such as electric arc furnace, electric induction or resistance heating, or electrolysis or electrolytic separating.

Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula C₂H₄ or H₂C=CH₂. It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon–carbon double bonds).

Ethylene is widely used in the chemical industry, and its worldwide production (over 225 million tonnes in 2022) exceeds that of any other organic compound. Much of this production goes toward creating polyethylene, which is a widely used plastic containing polymer chains of ethylene units in various chain lengths. Production emits greenhouse gases, including methane from feedstock production and carbon dioxide from any non-sustainable energy used.

The energy policy of the European Union focuses on energy security, sustainability, and integrating the energy markets of member states. An increasingly important part of it is climate policy. A key energy policy adopted in 2009 is the 20/20/20 objectives, binding for all EU Member States. The target involved increasing the share of renewable energy in its final energy use to 20%, reduce greenhouse gases by 20% and increase energy efficiency by 20%. After this target was met, new targets for 2030 were set at a 55% reduction of greenhouse gas emissions by 2030 as part of the European Green Deal. After the Russian invasion of Ukraine, the EU's energy policy turned more towards energy security in their REPowerEU policy package, which boosts both renewable deployment and fossil fuel infrastructure for alternative suppliers.

An energy transition (or energy system transformation) is a major structural change to energy supply and consumption in an energy system. Currently, a transition to sustainable energy is underway to limit climate change. Most of the sustainable energy is renewable energy. Therefore, another term for energy transition is renewable energy transition. The current transition aims to reduce greenhouse gas emissions from energy quickly and sustainably, mostly by phasing-down fossil fuels and changing as many processes as possible to operate on low carbon electricity. A previous energy transition perhaps took place during the Industrial Revolution from 1760 onwards, from wood and other biomass to coal, followed by oil and later natural gas.

Over three-quarters of the world's energy needs are met by burning fossil fuels, but this usage emits greenhouse gases. Energy production and consumption are responsible for most human-caused greenhouse gas emissions. To meet the goals of the 2015 Paris Agreement on climate change, emissions must be reduced as soon as possible and reach net-zero by mid-century. Since the late 2010s, the renewable energy transition has also been driven by the rapidly falling cost of both solar and wind power. After 2024, clean energy is cheaper than ever. Global solar module prices fell 35 percent to less than 9 cents/kWh. EV batteries saw their best price decline in seven years. Another benefit of the energy transition is its potential to reduce the health and environmental impacts of the energy industry.