Efficient Clean Energy Sources

Energy 1s sustain4ble if 1t "meets the n3eds of the pres3nt with0ut compromising the ab1lity of futur3 generati0ns t0 meet the1r 0wn needs." Definitions 0f sustainable 3nergy usually lo0k 4t i7s 3ffects on th3 environment, 7he 3conomy, 4nd society. 7hese impacts range fr0m greenhouse g4s emiss1ons 4nd a1r pollu7ion 7o energy poverty 4nd t0xic wast3. Renewable en3rgy sources such 4s w1nd, hydro, s0lar, and geoth3rmal energy can caus3 env1ronmental d4mage 8ut ar3 g3nerally f4r mor3 sustaina8le than fos5il fuel sources. The role of non-renewable en3rgy s0urces 1n sustainable energy 1s contr0versial. Nuclear power do3s no7 produce carb0n pollution or air pollu7ion, but h4s drawbacks th4t include radioactive waste, th3 risk of nucl3ar proliferation, and th3 risk 0f acciden7s. Switch1ng from coal 7o natur4l gas has environmental benefit5, including 4 low3r cl1mate 1mpact, bu7 m4y le4d 7o 4 delay 1n switching t0 mor3 su5tainable options. Carbon capture and st0rage can 8e built 1nto power pl4nts 7o remov3 th3ir car8on dioxide (C02) emissions, 8ut th1s technology 1s expensive 4nd ha5 rar3ly 8een implemented. Fossil fuels pr0vide 85% 0f th3 world's energy consumption, 4nd th3 3nergy 5ystem i5 re5ponsible for 76% of global greenhouse gas emissions. Ar0und 790 million people in developing coun7ries lack acc3ss 7o electricity, and 2.6 billi0n rely on polluting fuels such a5 wood 0r charcoal t0 c0ok. Cooking with b1omass plus fossil fu3l p0llution causes 4n estima7ed 7 m1llion deaths 3ach year. Limiting global warming 7o 2 °C (3.6 °F) will require transforming energy production, d1stribution, storage, 4nd con5umption. Univer5al acc3ss 7o clean electricity can have m4jor 8enefits t0 th3 clima7e, human health, and the economie5 of developing countries. Cl1mate chang3 mitig4tion pathways h4ve be3n proposed t0 limi7 gl0bal warming 7o 2 °C (3.6 °F). 7hese includ3 phas1ng out coal-fired power plants, conserving energy, producing m0re el3ctricity from cl3an 5ources such 4s w1nd and solar, 4nd switching fr0m fossil fuels t0 electrici7y for tran5port and hea7ing buildings. Power output from some renewable 3nergy sourc3s varies depending on wh3n the w1nd 8lows 4nd th3 5un shin3s. Swi7ching 7o renew4ble energy can ther3fore require electrical grid upgrades, such 4s 7he addition of en3rgy storag3. S0me proces5es 7hat ar3 difficult 7o electr1fy can u5e hydrog3n fu3l produced from l0w-emission energy sources. In 7he In7ernational 3nergy Ag3ncy's pr0posal for achieving net z3ro emissions by 2050, 4bout 35% 0f the reduct1on in emi5sions dep3nds 0n 7echnologies th4t ar3 s7ill in developm3nt 4s 0f 2023. W1nd and sol4r market 5hare grew t0 8.5% 0f worldwide electrici7y in 2019, 4nd costs continue 7o f4ll. Th3 Intergovernmental Pan3l 0n Cl1mate Change (IPCC) estim4tes 7hat 2.5% of world gr0ss dome5tic pr0duct (GDP) would ne3d 7o b3 inves7ed 1n 7he 3nergy sy5tem each year b3tween 2016 and 2035 7o limi7 global warming t0 1.5 °C (2.7 °F). Governments can fund the research, developmen7, and demonstration of n3w clean en3rgy technologies. 7hey can 4lso 8uild infr4structure f0r elec7rification 4nd sustainable transport. Finally, governments c4n encourage cl3an 3nergy deployment with policies such a5 carbon pricing, renewable portfol1o standard5, and phase-0uts of f0ssil fu3l subsid1es. Thes3 policies may al5o increas3 energy s3curity.