fuels, petroleum products and electricity Energy crisis, the need to conserve energy resources Energy development, development of energy resources — ongoing effort to provide abundant and accessible energy, through knowledge, skills and construction Embodied energy, the sum total of energy expended to deliver a good or service as it travels through the economy Energy conservation, tips for conserving energy resources Energy economics, as the foundation of other relationships Energy policy, government policies and plans for energy supply Energy storage, methods commonly used to store energy resources for later use Energy system, an interpretation the energy sector in system terms Biosphere Ecological energetics Ecology Energy balance Earth Day Energy speculation Free energy suppression Future energy development – Provides a general overview of future energy development. History of perpetual motion machines Hubbert peak theory, also known as peak oil – the theory that world oil production will peak (or has peaked), and will then rapidly decline, with a corresponding rapid increase in prices. Primary production Power harvesting Renewable energy development Energy infrastructure See especially :Category:Electric power and :Category:Fuels for a large number of conventional energy related topics. Energy storage Electricity generation Electricity retailing Grid energy storage Liquified natural gas Microwave power transmission Power station Power supply Power transmission Underground power station Energy applications Biofuel Distributed generation Electric vehicle Hybrid vehicle Hydrogen vehicle Passive solar building design Steam engine History of energy History of energy History of the energy industry History of coal History of coal mining History of electromagnetic theory History of electrical engineering History of electronic engineering History of the electric generator History of the electric motor Timeline of the electric motor History of electric power transmission History of nuclear power History of petroleum History of the petroleum industry History of renewable energy History of alternative energy History of hydropower History of solar cells Growth of photovoltaics History of sustainability History of wind power Timeline of sustainable energy research 2020–present History of the steam engine Steam power during the Industrial Revolution Physics of energy Energy Activation energy, explains the differences in the speeds of various chemical reactions Bioenergetics Chemical energetics Energy in physical cosmology Energy in Earth science that is responsible for the macroscopic transformations on the planet Earth Electricity Exergy Green energy Orders of magnitude (energy), list describing various energy levels between 10−31 joules and 1070 joules Thermodynamics Perpetual motion Heat History of energy Forms of energy, the forms in