question: How does the "harvesting" if renewable energy work? How do windmills get power from spinning? How do solar panels make energy from the sun? How does the conversion of the energy from one to another work?
comment: This is all ELI5 levels of course. I don't know enough detail to ELI10 Windmills are blown by wind - the wind collides with the blades and causes them to turn. The windmill is linked to a big-ass magnet, and that big-ass magnet is inside a big-ass coil of wire. When the big-ass magnet rotates, it energises electrons within the wires, creating electricity. In solar panels, photons from sunlight bash into electrons within the solar panel. This gives them energy and causes them to become free from their host atoms. They run into metal 'collection' plates, and then into wires from there.
passages: Section::::Renewable energy sources.:Wind.
  
  In Europe in the 19th century, there were about 200,000 windmills, slightly more than the modern wind turbines of the 21st century. They were mainly used to grind grain and to pump water. The age of coal powered steam engines replaced this early use of wind power.
   Section::::Devices.:Atmospheric pressure changes.
  
  The pressure of the atmosphere changes naturally over time from temperature changes and weather patterns. Devices with a sealed chamber can use these pressure differences to extract energy. This has been used to provide power for mechanical clocks such as the Atmos clock.
  
  Section::::Devices.:Ocean Energy.
   Plant energy is produced by crops specifically grown for use as fuel that offer high biomass output per hectare with low input energy. The grain can be used for liquid transportation fuels while the straw can be burned to produce heat or electricity. Plant biomass can also be degraded from cellulose to glucose through a series of chemical treatments, and the resulting sugar can then be used as a first generation biofuel.
   List of books about renewable energy
  
  This is a bibliography of renewable energy.
  
  Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable (naturally replenished). About 16% of global final energy consumption comes from renewables, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4% from hydroelectricity. New renewables (small hydro, modern biomass, wind, solar, geothermal, and biofuels) account for another 3% and are growing very rapidly.
   Section::::Operation.:Accumulating energy.
  
  Energy can also be harvested to power small autonomous sensors such as those developed using MEMS technology. These systems are often very small and require little power, but their applications are limited by the reliance on battery power. Scavenging energy from ambient vibrations, wind, heat or light could enable smart sensors to be functional indefinitely.
   BULLET::::- geographically dispersed variable energy sources, concentrated solar power (CSP) and hydro power
  
  BULLET::::- storage facilities: pumped hydro, as heat in CSP plants, in batteries, as hydrogen by electrolysis of water, or as compressed air underground.
  
  Section::::Places with near 100% renewable electricity.
  
  The following places meet 90% or more of their average yearly electricity demand with renewable energy (incomplete list):
   Section::::Overview.
  
  Renewable energy flows involve natural phenomena such as sunlight, wind, tides, plant growth, and geothermal heat, as the International Energy Agency explains:
   BULLET::::- The windmill was a very early wind turbine. In a solar updraft tower wind is artificially produced. Before 2010 less than 2% of the world's electricity was produced from wind.
  
  Although turbines are most common in commercial power generation, smaller generators can be powered by gasoline or diesel engines. These may used for back up a generation or isolated villages.
  
  Section::::Production.
  
  Total worldwide gross production of electricity in 2016 was 25,082TWh. Sources of electricity were coal and peat 38.3%, natural gas 23.1%, hydroelectric 16.6%, nuclear power 10.4%, oil 3.7%, solar/wind/geothermal/tidal/other 5.6%, biomass and waste 2.3%.
   Section::::Renewable sources.:Wind.
  
  Wind power harnesses the power of the wind to propel the blades of wind turbines. These turbines cause the rotation of magnets, which creates electricity. Wind towers are usually built together on wind farms. There are offshore and onshore wind farms. Global wind power capacity has expanded rapidly to 336 GW in June 2014, and wind energy production was around 4% of total worldwide electricity usage, and growing rapidly.
   By the end of 2011, total renewable power capacity worldwide exceeded 1,360 GW, up 8%. Renewables producing electricity accounted for almost half of the 208 GW of capacity added globally during 2011. Wind and solar photovoltaics (PV) accounted for almost 40% and 30%. Based on REN21's 2014 report, renewables contributed 19 percent to our energy consumption and 22 percent to our electricity generation in 2012 and 2013, respectively. This energy consumption is divided as 9% coming from traditional biomass, 4.2% as heat energy (non-biomass), 3.8% hydro electricity and 2% electricity from wind, solar, geothermal, and biomass.
   Conventional hydroelectricity, biomass and geothermal are completely dispatchable as each has a store of potential energy; wind and solar production are typically without storage and can be decreased, but not dispatched, other than when nature provides. Between wind and solar, solar has a more variable daily cycle than wind, but is more predictable in daylight hours than wind. Like solar, tidal energy varies between on and off cycles through each day, unlike solar there is no intermittentcy, tides are available every day without fail. Biofuel and biomass involve multiple steps in the production of energy – growing plants, harvesting, processing, transportation, storage and burning to create heat for electricity, transportation or space heating. In the combined power plant used by the University of Kassel to simulate using 100% renewable energy, wind farms and solar farms were supplemented as needed by hydrostorage and biomass to follow the electricity demand.
   A wind farm is a group of wind turbines in the same location used to produce electric power. A large wind farm may consist of several hundred individual wind turbines, and cover an extended area of hundreds of square miles, but the land between the turbines may be used for agricultural or other purposes. A wind farm may also be located offshore.
   Lists of renewable energy topics
  
  Renewable energy is generally defined as energy that comes from resources which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy replaces conventional fuels in four distinct areas: electricity generation, air and water heating/cooling, motor fuels, and rural (off-grid) energy services. Based on REN21's 2014 report, renewables contributed 19 percent to our global energy consumption and 22 percent to our electricity generation in 2012 and 2013, respectively.
  
  These are lists about renewable energy:
  
  BULLET::::- Index of solar energy articles
   Energy harvesting
  
  Energy harvesting (also known as power harvesting or energy scavenging or ambient power) is the process by which energy is derived from external sources (e.g., solar power, thermal energy, wind energy, salinity gradients, and kinetic energy, also known as ambient energy), captured, and stored for small, wireless autonomous devices, like those used in wearable electronics and wireless sensor networks.
   BULLET::::- Solar updraft tower
  
  BULLET::::- Space-based solar power
  
  Section::::Debate.
  
  Renewable electricity production, from sources such as wind power and solar power, is sometimes criticized for being variable or intermittent, but is not true for concentrated solar, geothermal and biofuels, that have continuity. In any case, the International Energy Agency has stated that deployment of renewable technologies usually increases the diversity of electricity sources and, through local generation, contributes to the flexibility of the system and its resistance to central shocks.
   In 2014 global wind power capacity expanded 16% to 369,553 MW. Yearly wind energy production is also growing rapidly and has reached around 4% of worldwide electricity usage, 11.4% in the EU, and it is widely used in Asia, and the United States. In 2015, worldwide installed photovoltaics capacity increased to 227 gigawatts (GW), sufficient to supply 1 percent of global electricity demands. Solar thermal energy stations operate in the United States and Spain, and as of 2016, the largest of these is the 392 MW Ivanpah Solar Electric Generating System in California. The world's largest geothermal power installation is The Geysers in California, with a rated capacity of 750 MW. Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane, and ethanol now provides 18% of the country's automotive fuel. Ethanol fuel is also widely available in the United States.
   BULLET::::- Micro wind turbine are used to harvest wind energy readily available in the environment in the form of kinetic energy to power the low power electronic devices such as wireless sensor nodes. When air flows across the blades of the turbine, a net pressure difference is developed between the wind speeds above and below the blades. This will result in a lift force generated which in turn rotate the blades. Similar to photovoltaics, wind farms have been constructed on an industrial scale and are being used to generate substantial amounts of electrical energy.
   Section::::Technologies and set-up.:Extra equipment needed besides the power plant.:Wind turbine specific.:Vibro-wind power.
  
  A new wind energy technology is being developed that converts energy from wind energy vibrations to electricity. This energy, called Vibro-Wind technology, can use winds of less strength than normal wind turbines, and can be placed in almost any location.
   Green certificate
  
  A green certificate – terminology predominantly used in Europe but now becoming more widespread globally – are a tradable commodity proving that certain electricity is generated using renewable energy sources. Typically one certificate represents the generation of one Megawatthour of electricity. What is defined as "renewable" varies from certificate trading scheme to trading scheme. Usually, at least the following sources are considered as renewable:
  
  BULLET::::- Wind (often further divided into onshore and offshore)
  
  BULLET::::- Solar (often further divided into photovoltaic and thermal)
   Section::::Market and industry trends.:Trends for individual technologies.:Wind power development.
   Renewable energy
  
  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. 
   Other sources of energy from trees include capturing the physical movement of the tree in a generator. Theoretical analysis of this source of energy shows some promise in powering small electronic devices. A practical device based on this theory has been built and successfully powered a sensor node for a year.
  
  Section::::Devices.:Metamaterial.
   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. worldwide, more than half of all new electricity capacity installed was renewable.
   Renewable electricity can be generated by hydropower, solar, wind, geothermal and by burning biomass. In a few countries where renewable electricity is inexpensive, resistance heating is common. In countries like Denmark where electricity is expensive, it is not permitted to install electric heating as the main heat source. Wind turbines have more output at night when there is a small demand for electricity, storage heaters consume this lower cost electricity at night and give off heat during the day.
  
  Section::::Leading renewable heat technologies.:Wood-pellet heating.
   The theory of peak oil was published in 1956. In the 1970s environmentalists promoted the development of renewable energy both as a replacement for the eventual depletion of oil, as well as for an escape from dependence on oil, and the first electricity-generating wind turbines appeared. Solar had long been used for heating and cooling, but solar panels were too costly to build solar farms until 1980.
  
  Section::::Mainstream technologies.
  
  Section::::Mainstream technologies.:Wind power.
  
  In 2018, worldwide installed capacity of wind power was 564 GW.
  