I have a very distinct memory of tv tellingme, quot;every hour the sun beams enough solar energy to power our planet for a year.quot; Solarpower, however, has yet to deliver on this promise from my children’s television. Whyis it so hard???? The sun shines on us every day, it comes downhere we gather it up and we use it for energy boom boom boom, done! But it’s slightlymore complicated than that, as you know. In 1873, electrical engineer Willoughby Smithdiscovered the element selenium was photoconductive when exposed to sunlight the metallic formof selenium becomes a semiconductor! Three years later, other scientists discovered seleniumcould be used to create electricity from sunlight
dubbed the photoelectric effect. When sunlighthits a metal like selenium the electromagnetic radiation is absorbed into it this fueleda whole HOST of physics nerds who are still arguing whether light is a particle or a waveto this day! It was such a big deal the 1921 Nobel Prize in physics was awarded to AlbertEinstein for explaining the photoelectric effect, and for his contributions to theoreticalphysicsâ€¦ or whatever. Eventually, scientists discovered that thelight energy causes the freeing of electrons which, if captured, could be used to generateelectricity!. This photoelectric effect has since been cultivated and researched and cultivatedagain, and the discovery that many different
elements display a photoelectric effect openedit up for use in a number of inventions! Photosensitive cells are used in televisions, industrialprocesses, telecommunications, fiber optics, copy machines, spectroscopy and telescopy,and to sense pollution or emphasize other lights like in night vision or infrared cameras;plus, of course, solar panels via a photovoltaic cell. Photovoltaics were invented in the 1950s,and were popularized by the space program as a way to power satellites. In the 1970s,pushes were made to modernize photovoltaics for use in commercial and residential power but consumers mainly used them for calculators, watches, radios and the like. Like a battery,a photovoltaic cell has a positive and negative
to guide the electrons into the system. Eachcell uses a pair of silicon wafers one doped with phosphorous (negative) and onewith boron (positive). From 1995 to 2010 solar energy use grew 20percent a year and now, new inventions are making it even more affordable. Firstly,in 2009, China created way more solar panels than the market needed, and the price collapsed.And secondly, state and federal governments in the United States, Germany, the UnitedKingdom and Japan are all giving subsidies to cultivate better renewable energy systems.This means more supply and demand for this technology, and as money flows through renewables,they get better!
Recently the University of Queen Mary in Londonrevealed they can turn shrimp shells into cheap solar panels. The shells of crustaceanscontain chitin and chitosan which can be extracted into CQD or carbon quantum dots CQD solarcells aren’t new, but usually use expensive ruthenium for its photoelectric properties.Instead, the researchers found this biomass byproduct of the shrimp industry can be usedto extract CQDs and create fully renewable, cheap solar cells! Pretty cool, huh? Fortunately solar cellsaren’t the only place finding greener solutions for energy use Toyota is, too! The newToyota Mirai is looking to the future with
sustainability in mind; fueled by hydrogenand leaving zero emissions behind. Every year renewable energy is getting better,but it’s not yet as efficient as we’d hope. For more on the efficiency of the most commontypes of energy production, check out my tutorial about that here What do YOU think is the most promising typeof energy? Solar? Wind? Nuclear? Or plain old coal, oil and gas? Why? Tell me your thoughtsin the comments, and thanks for watching. If you haven’t subscribed yet, why not? Godo it! We need you here! Thanks again..
Can We Rely on Wind and Solar Energy
Are wind and solar power the answer to ourenergy needs? There’s a lot of sun and a lot of wind. They’re free. They’re clean.No CO2 emissions. So, what’s the problem? Why do solar and wind combined provide lessthan 2% of the world’s energy? To answer these questions, we need to understandwhat makes energy, or anything else for that matter, cheap and plentiful.For something to be cheap and plentiful, every part of the process to produce it, includingevery input that goes into it, must be cheap and plentiful.Yes, the sun is free. Yes, wind is free. But the process of turning sunlight and wind intouseable energy on a mass scale is far from free.
In fact, compared to the other sourcesof energy fossil fuels, nuclear power, and hydroelectric power, solar and wind powerare very expensive. The basic problem is that sunlight and windas energy sources are both weak (the more technical term is dilute) and unreliable (themore technical term is intermittent). It takes a lot of resources to collect and concentratethem, and even more resources to make them available ondemand. These are called thediluteness problem and the intermittency problem. The diluteness problem is that, unlike coalor oil, the sun and the wind don’t deliver concentrated energy which means you needa lot of additional materials
to produce a unit of energy.For solar power, such materials can include highly purified silicon, phosphorus, boron,and a dozen other complex compounds like titanium dioxide. All these materials have to be mined,refined and/or manufactured in order to make solar panels. Those industrial processes takea lot of energy. For wind, needed materials include highperformancecompounds for turbine blades and the rareearth metal neodymium for lightweight, specialtymagnets, as well as the steel and concrete necessary to build structures thousandsof them as tall as skyscrapers. And as big a problem as diluteness is, it’snothing compared to the intermittency problem.
This isn’t exactly a news flash, but thesun doesn’t shine all the time. And the wind doesn’t blow all the time. The onlyway for solar and wind to be truly useful would be if we could store them so that theywould be available when we needed them. You can store oil in a tank. Where do you storesolar or wind energy? No such massstorage system exists. Which is why, in the entireworld, there is not one real or proposed independent, freestanding solar or wind power plant. Allof them require backup. And guess what the goto backup is: fossil fuel.Here’s what solar and wind electricity look like in Germany, which is the world’s leaderin â€œrenewablesâ€�. The word erratic leaps to mind.
Wind is constantly varying, sometimesdisappearing completely. And solar produces little in the winter months when Germany most needs energy. Therefore, some reliable source of energyis needed to do the heavy lifting. In Germany’s case that energy is coal. So, while Germanyhas spent tens of billions of dollars to subsidize solar panels and windmills, fossil fuel usein that nation has not decreased, it’s increased and less than 10% of their total energyis generated by solar and wind. Furthermore, switching back and forth betweensolar and wind and coal to maintain a steady flow of energy is costly. Utility bills forthe average German have gone up so dramatically
that â€œenergy povertyâ€� has become a popularterm to describe those who cannot pay or who can barely pay their electricity bills.If those bills one day go down, the reason will not be more solar and wind energy, butlower oil and coal prices. There’s no free lunch. And there’s nofree energy. And that very much includes the highly expensive energy from the sun and thewind. I’m Alex Epstein of the Center for IndustrialProgress, for Prager University..