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Solar Home Power System

It’s 2015, I always thought the world looklike the jetsons right now with flying cars and clean energy? While we’re still waitingon a flying car, clean energy, especially solar, has come a long away. Hey guys Julia here for DNews We’ve talked about solar power here on DNewsbefore a lot. To see how solar power works check out this episode right here. But justa quick recap, solar panels are made of photovoltaic cells. These cells convert sunlight into energyby using photons from the sun to knock loose electrons. These cells are typically madeup of a silicon wafer sandwich. One wafer

is positively charged, the other negative,this creates an electric field. Phosphorus is added to top the layer to increase theamount of electrons there and boron makes the bottom more positive. Photons from thesun knock an electron out of that electrical field and then the cell has some other partsthat use that electron as energy. That’s the basics. Solar panels aren’ta new technology, they’ve been around for over a hundred years. The first “solar cellâ€�was patented in 1888. But since then, it’s kind of been slow going. Almost 90 years laterRCA Laboratories come out with the silicon version of a solar cell… but it only hadan efficiency of 1.1% Basically that means

for the amount of energy going into a solarcell from the sun, only 1.1% of that is converted into usable electricity. And research into solar technology is likeI said, slow going. One researcher said gains of 0.2 percent are the norm and gains of 1percent are seen as significant breakthroughs. Since the 70s efficiency has only increasedfrom 1.1% to around 20% for most conventional models. In comparison traditional forms ofelectricity from fossil fuels are only at about 40% efficient. But even the US Government wants to do better.Over a decade ago the DARPA initiative put

out a request for 50% efficiency in solarpanels. So far, research has come close. In 2007 researchers from the University of Delawareannounced they created a cell with 42.8 percent efficiency up from 40%, which in this fieldwas a huge deal. Their solar panel gained in efficiency by separating sunlight intothree different energy bins of high, medium and low, and directs them onto cells of variouslightsensitive materials to cover the solar spectrum. And in late 2014 Australian researchersannounce a 40% efficient panel in the journal Progress in Photovoltaics. It boosted efficiencyby including another filter to capture more bandwidths of light that are usually wastedby other models. But it’s still not the

typical model you’d see on homes. Most conventionalpanels only reach an efficiency of about 20%. But maybe the future doesn’t even lie withsilicon. Research into a different material called perovskite has taken off over the pastfew years. Perovskite is a naturally occurring mineral with a crystalline structure madeout of calcium and titanium. But it’s really easy to synthesize in a lab out of a organicinorganichybrid of lead or tin halide that’s mixed with organic groups like methylammonium. The crystalline structure makes it especiallygood for solar applications. But one of the most exciting things about this new type ofsolar cell is how far it’s come in such

a short time. Perovskite research seems tobe moving at very brisk pace compared to silicon. In only six years it jumped from 3.8% efficiencyin 2009 to a certified 20.1% in 2015, which is on par with conventional silicon panels.So maybe they could reach DARPA’s goal in no time. One materials scientist I spoke with,Daniel Dryden said “their insane rate of improvement is definitely worth paying attentionto as more than just the newest fad.â€�. While perovskite panels aren’t on the marketyet, some start ups promise they’ll have some ready to go by 2017. So it’s definitelysomething to keep an eye on. One of the other great features of perovskitethat gets researchers excited is how cheap

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