Query: Germany managed to increase its use of renewables and its output of carbon dioxide at the same time -- because it resorted to cheap coal to keep the lights on at a price its people could afford.

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Carbon dioxide <=SEP=> Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas .   As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product .   Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas .   It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting .   Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .

Electricity generation <=SEP=> Electricity generation is the process of generating electric power from sources of primary energy . For electric utilities , it is the first process in the delivery of electricity to consumers . The other processes as transmission , distribution , energy storage and recovery using pumped-storage methods are normally carried out by the electric power industry . Electricity is most often generated at a power station by electromechanical generators , primarily driven by heat engines fuelled by combustion or nuclear fission but also by other means such as the kinetic energy of flowing water and wind . Other energy sources include solar photovoltaics and geothermal power .

Solar power <=SEP=> Solar power is the conversion of energy from sunlight into electricity , either directly using photovoltaics ( PV ) , or indirectly using concentrated solar power . Concentrated solar power systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam . Photovoltaic cells convert light into an electric current using the photovoltaic effect .   Photovoltaics were initially solely used as a source of electricity for small and medium-sized applications , from the calculator powered by a single solar cell to remote homes powered by an off-grid rooftop PV system . Commercial concentrated solar power plants were first developed in the 1980s . The 392 MW Ivanpah installation is the largest concentrating solar power plant in the world , located in the Mojave Desert of California .   As the cost of solar electricity has fallen , the number of grid-connected solar PV systems has grown into the millions and utility-scale solar power stations with hundreds of megawatts are being built . Solar PV is rapidly becoming an inexpensive , low-carbon technology to harness renewable energy from the Sun . The current largest photovoltaic power station in the world is the 850 MW Longyangxia Dam Solar Park , in Qinghai , China .   The International Energy Agency projected in 2014 that under its `` high renewables '' scenario , by 2050 , solar photovoltaics and concentrated solar power would contribute about 16 and 11 percent , respectively , of the worldwide electricity consumption , and solar would be the world 's largest source of electricity . Most solar installations would be in China and India . Currently , as of 2016 , solar power provides just 1 % of total worldwide electricity production but growing 33 % per annum .

Sustainable energy <=SEP=> Sustainable energy is energy that is consumed at insignificant rates compared to its supply and with manageable collateral effects , especially environmental effects . Another common definition of sustainable energy is an energy system that serves the needs of the present without compromising the ability of future generations to meet their needs . The organizing principle for sustainability is sustainable development , which includes the four interconnected domains : ecology , economics , politics and culture . Sustainability science is the study of sustainable development and environmental science .   Technologies promote sustainable energy including renewable energy sources , such as hydroelectricity , solar energy , wind energy , wave power , geothermal energy , bioenergy , tidal power and also technologies designed to improve energy efficiency . Costs have fallen dramatically in recent years , and continue to fall . Most of these technologies are either economically competitive or close to being so . Increasingly , effective government policies support investor confidence and these markets are expanding . Considerable progress is being made in the energy transition from fossil fuels to ecologically sustainable systems , to the point where many studies support 100 % renewable energy .

Germany <=SEP=> Germany ( listen ) , is a federal parliamentary republic in central-western Europe . It includes 16 constituent states , covers an area of 357,021 km2 , and has a largely temperate seasonal climate . With about 82 million inhabitants , Germany is the most populous member state of the European Union . After the United States , it is the second most popular immigration destination in the world . Germany 's capital and largest metropolis is Berlin , while its largest conurbation is the Ruhr ( main centres : Dortmund and Essen ) . The country 's other major cities are Hamburg , Munich , Cologne , Frankfurt , Stuttgart , Düsseldorf , Leipzig , Bremen , Dresden , Hannover and Nuremberg .   Various Germanic tribes have inhabited the northern parts of modern Germany since classical antiquity . A region named Germania was documented before 100 AD . During the Migration Period the Germanic tribes expanded southward . Beginning in the 10th century , German territories formed a central part of the Holy Roman Empire . During the 16th century , northern German regions became the centre of the Protestant Reformation . The remains of the Holy Roman Empire formed the German Confederation in 1815 , while the German revolutions of 1848 -- 49 established major democratic rights first .   In 1871 , Germany became a nation state when most of the German states were unified into the Prussian-dominated German Empire . After World War I and the German Revolution of 1918 -- 1919 , the Empire was replaced by the parliamentary Weimar Republic . In 1933 the Nazi seizure of power quickly led to the establishment of Nazi Germany which was built upon a dictatorship and consequently led to World War II and one of the biggest genocides in history , the Holocaust . By 1945 Germany and most of Europe were left in destruction and ruins . After the end of World War II in Europe and a period of Allied occupation , two German states were founded : the democratic Federal Republic of Germany ( commonly known as West Germany ) and the socialist German Democratic Republic ( commonly known as East Germany ) . A wall encircling West Berlin was created on August 13 , 1961 , and was torn down on November 9 , 1989 . On 3 October 1990 , the country was reunified .   In the 21st century , Germany is a great power and has the world 's fourth-largest economy by nominal GDP , as well as the fifth-largest by PPP . As a global leader in several industrial and technological sectors , it is both the world 's third-largest exporter and importer of goods . Germany is a developed country with a very high standard of living sustained by a skilled and productive society . It upholds a social security and universal health care system , environmental protection and a tuition-free university education .   The Federal Republic of Germany was a founding member of the European Economic Community in 1957 and the European Union in 1993 . It is part of the Schengen Area , and became a co-founder of the Eurozone in 1999 . Germany is a member of the United Nations , NATO , the G8 , the G20 , and the OECD . The national military expenditure is the 9th highest in the world . Known for its rich cultural history , Germany has been continuously the home of influential and successful artists , philosophers , musicians , sportspeople , entrepreneurs , scientists , engineers , and inventors .