Query: Solar panels drain the sun's energy.

Relevant passages:
Solar panel <=SEP=> Solar panels absorb the sunlight as a source of energy to generate electricity or heat .   A photovoltaic ( PV ) module is a packaged , connect assembly of typically 6x10 photovoltaic solar cells . Photovoltaic modules constitute the photovoltaic array of a photovoltaic system that generates and supplies solar electricity in commercial and residential applications . Each module is rated by its DC output power under standard test conditions ( STC ) , and typically ranges from 100 to 365 Watts ( W ) . The efficiency of a module determines the area of a module given the same rated output an 8 % efficient 230 W module will have twice the area of a 16 % efficient 230 W module . There are a few commercially available solar modules that exceed efficiency of 22 % and reportedly also exceeding 24 % . A single solar module can produce only a limited amount of power ; most installations contain multiple modules . A photovoltaic system typically includes an array of photovoltaic modules , an inverter , a battery pack for storage , interconnection wiring , and optionally a solar tracking mechanism .   The most common application of solar panels is solar water heating systems .   The price of solar power has continued to fall so that in many countries it is cheaper than ordinary fossil fuel electricity from the grid ( there is `` grid parity '' ) .

Solar energy <=SEP=> Solar energy is radiant light and heat from the Sun that is harnessed using a range of ever-evolving technologies such as solar heating , photovoltaics , solar thermal energy , solar architecture , molten salt power plants and artificial photosynthesis .   It is an important source of renewable energy and its technologies are broadly characterized as either passive solar or active solar depending on how they capture and distribute solar energy or convert it into solar power . Active solar techniques include the use of photovoltaic systems , concentrated solar power and solar water heating to harness the energy . Passive solar techniques include orienting a building to the Sun , selecting materials with favorable thermal mass or light-dispersing properties , and designing spaces that naturally circulate air .   The large magnitude of solar energy available makes it a highly appealing source of electricity . The United Nations Development Programme in its 2000 World Energy Assessment found that the annual potential of solar energy was 1,575 -- 49,837 exajoules ( EJ ) . This is several times larger than the total world energy consumption , which was 559.8 EJ in 2012 .   In 2011 , the International Energy Agency said that `` the development of affordable , inexhaustible and clean solar energy technologies will have huge longer-term benefits . It will increase countries ' energy security through reliance on an indigenous , inexhaustible and mostly import-independent resource , enhance sustainability , reduce pollution , lower the costs of mitigating global warming , and keep fossil fuel prices lower than otherwise . These advantages are global . Hence the additional costs of the incentives for early deployment should be considered learning investments ; they must be wisely spent and need to be widely shared '' .

Renewable energy <=SEP=> Renewable energy is energy that is collected from renewable resources , which are naturally replenished on a human timescale , such as sunlight , wind , rain , tides , waves , and geothermal heat . Renewable energy often provides energy in four important areas : electricity generation , air and water heating/cooling , transportation , and rural ( off-grid ) energy services .   Based on REN21 's 2016 report , renewables contributed 19.2 % to humans ' global energy consumption and 23.7 % to their generation of electricity in 2014 and 2015 , respectively . This energy consumption is divided as 8.9 % coming from traditional biomass , 4.2 % as heat energy ( modern biomass , geothermal and solar heat ) , 3.9 % hydro electricity and 2.2 % is electricity from wind , solar , geothermal , and biomass . Worldwide investments in renewable technologies amounted to more than US$ 286 billion in 2015 , with countries like China and the United States heavily investing in wind , hydro , solar and biofuels . Globally , there are an estimated 7.7 million jobs associated with the renewable energy industries , with solar photovoltaics being the largest renewable employer . As of 2015 worldwide , more than half of all new electricity capacity installed was renewable .   Renewable energy resources exist over wide geographical areas , in contrast to other energy sources , which are concentrated in a limited number of countries . Rapid deployment of renewable energy and energy efficiency is resulting in significant energy security , climate change mitigation , and economic benefits . The results of a recent review of the literature concluded that as greenhouse gas ( GHG ) emitters begin to be held liable for damages resulting from GHG emissions resulting in climate change , a high value for liability mitigation would provide powerful incentives for deployment of renewable energy technologies . In international public opinion surveys there is strong support for promoting renewable sources such as solar power and wind power . At the national level , at least 30 nations around the world already have renewable energy contributing more than 20 percent of energy supply . National renewable energy markets are projected to continue to grow strongly in the coming decade and beyond . Some places and at least two countries , Iceland and Norway generate all their electricity using renewable energy already , and many other countries have the set a goal to reach 100 % renewable energy in the future . For example , in Denmark the government decided to switch the total energy supply ( electricity , mobility and heating/cooling ) to 100 % renewable energy by 2050 .   While many renewable energy projects are large-scale , renewable technologies are also suited to rural and remote areas and developing countries , where energy is often crucial in human development . United Nations ' Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity . As most of renewables provide electricity , renewable energy deployment is often applied in conjunction with further electrification , which has several benefits : Electricity can be converted to heat ( where necessary generating higher temperatures than fossil fuels ) , can be converted into mechanical energy with high efficiency and is clean at the point of consumption . In addition to that electrification with renewable energy is much more efficient and therefore leads to a significant reduction in primary energy requirements , because most renewables do n't have a steam cycle with high losses ( fossil power plants usually have losses of 40 to 65 % ) .   Renewable energy systems are rapidly becoming more efficient and cheaper . Their share of total energy consumption is increasing . Growth in consumption of coal and oil could end by 2020 due to increased uptake of renewables and natural gas .

Photovoltaics <=SEP=> Photovoltaics ( PV ) is a term which covers the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect , a phenomenon studied in physics , photochemistry , and electrochemistry .   A typical photovoltaic system employs solar panels , each comprising a number of solar cells , which generate electrical power . PV installations may be ground-mounted , rooftop mounted or wall mounted . The mount may be fixed , or use a solar tracker to follow the sun across the sky .   Solar PV has specific advantages as an energy source : its operation generates no pollution and no greenhouse gas emissions once installed , it shows simple scalability in respect of power needs and silicon has large availability in the Earth 's crust .   PV systems have the major disadvantage that the power output is dependent on direct sunlight , so about 10-25 % is lost if a tracking system is not used , since the cell will not be directly facing the sun at all times . Dust , clouds , and other things in the atmosphere also diminish the power output . Another main issue is the concentration of the production in the hours corresponding to main insolation , which do n't usually match the peaks in demand in human activity cycles . Unless current societal patterns of consumption and electrical networks mutually adjust to this scenario , electricity still needs to be made up by other power sources , usually hydrocarbon .   Photovoltaic systems have long been used in specialized applications , and standalone and grid-connected PV systems have been in use since the 1990s . They were first mass-produced in 2000 , when German environmentalists and the Eurosolar organization got government funding for a ten thousand roof program .   Advances in technology and increased manufacturing scale have in any case reduced the cost , increased the reliability , and increased the efficiency of photovoltaic installations .  Net metering and financial incentives , such as preferential feed-in tariffs for solar-generated electricity , have supported solar PV installations in many countries . More than 100 countries now use solar PV .   After hydro and wind powers , PV is the third renewable energy source in terms of globally capacity . In 2014 , worldwide installed PV capacity increased to 177 gigawatts ( GW ) , which is two percent of global electricity demand . China , followed by Japan and the United States , is the fastest growing market , while Germany remains the world 's largest producer , with solar PV providing seven percent of annual domestic electricity consumption . With current technology ( as of 2013 ) , photovoltaics recoups the energy needed to manufacture them in 1.5 years in Southern Europe and 2.5 years in Northern Europe .