Its 2015, i always thought the world look like the jetsons right now with flying cars and clean energy? While were still waiting on a flying car, clean energy, especially solar, has come a long away. Hey guys Julia here for DNews Weve talked about solar power here on DNews before a lot. To see how solar power works check out this episode right here. But just a quick recap, solar panels are made of photovoltaic.
Cells. these cells convert sunlight into energy by using photons from the sun to knock loose electrons. These cells are typically made up 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 the amount of electrons there and boron makes the bottom more positive. Photons from the sun knock an electron out of that electrical field and then the cell has some other parts that use that electron as energy.
Thats the basics. solar panels arent a new technology, theyve been around for over a hundred years. The first solar cell was patented in 1888. But since then, its kind of been slow going. Almost 90 years later RCA Laboratories come out with the silicon version of a solar cell but it only had an efficiency of 1.1% Basically that means for the amount of energy going into a solar cell from the sun, only 1.1% of that is converted into usable electricity.
And research into solar technology is like i said, slow going. one researcher said gains of 0.2 percent are the norm and gains of 1 percent are seen as significant breakthroughs. Since the 70s efficiency has only increased from 1.1% to around 20% for most conventional models. In comparison traditional forms of electricity 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 solar panels. so far, research has come close. in 2007 researchers from the University of Delaware announced they created a cell with 42.8 percent efficiency up from 40%, which in this field was a huge deal. Their solar panel gained in efficiency by separating sunlight into three different energy bins of high, medium and low, and directs them onto cells of various lightsensitive materials to cover the solar spectrum. And in late 2014 Australian researchers announce a 40% efficient panel in the journal.
Progress in photovoltaics. it boosted efficiency by including another filter to capture more bandwidths of light that are usually wasted by other models. But its still not the typical model youd see on homes. Most conventional panels only reach an efficiency of about 20%. But maybe the future doesnt even lie with silicon. Research into a different material called perovskite has taken off over the past few years. Perovskite is a naturally occurring mineral with a crystalline structure made out of calcium and titanium. But its really.
Easy to synthesize in a lab out of a organicinorganic hybrid of lead or tin halide that’s mixed with organic groups like methylammonium. The crystalline structure makes it especially good for solar applications. But one of the most exciting things about this new type of solar cell is how far its come in such a short time. Perovskite research seems to be moving at very brisk pace compared to silicon. In only six years it jumped from 3.8% efficiency in 2009 to a certified 20.1% in 2015, which.
Is on par with conventional silicon panels. so maybe they could reach darpas goal in no time. One materials scientist I spoke with, Daniel Dryden said their insane rate of improvement is definitely worth paying attention to as more than just the newest fad. While perovskite panels arent on the market yet, some start ups promise theyll have some ready to go by 2017. So its definitely something to keep an eye on. One of the other great features of perovskite that gets researchers excited is how cheap.
Changes in Solar Cell Technology Joseph von Fraunhofer Prize 2016
I grew up near freiburg and as a youth i fought against the planned atomic power plant in whyl. All my life I’ve tried to use energy as sparingly as possible and today it’s possible to generate and consume your own energy. That’s just fantastic! As could be expected Andreas Klatt generates his own electricity for his electric car, and he joined others to form the grassroots energy collective Genossenschaft BrgerEnergie Bodensee and helped build a solar farm. The farm’s collective photovoltaic modules supply enough electricity for approximately 700 people. The problem is always ground space. At over 40 acres our system is already relatively large.
Being able to produce more energy using the same amount of space would be a great advantage. Solar cells absorb sunlight and use it to make electricity. In conventional cells a large portion of the light is lost out the backside and is useless for generating electricity. These losses can be reduced by inserting an innovative intermediate layer into the backside of the solar cell. Scientists at the Freiburg Fraunhofer Institute for Solar Energy Systems ISE developed a way to produce these highefficiency cells in industrial series quantities, revolutionizing the photovoltaics market. By inserting a mirror into the back of the solar cell which is highly reflective of longwave photons, exactly those photons that previously were not absorbed.
When passing through the silicon wafer are reflected back into the cell, passing through the semiconductor several times and increasing electricity production. Since this mirror is not conductive and separates the semiconductor from the electrodes, thousands of minute connections have to be made through this layer so that electricity can flow from the wafer to the electrodes. Fraunhofer researchers achieved this with Laser Fired Contact technology. Each of the appr. 100,000 contacts is created with a single laser pulse. I have to find a laser process that’s strong enough to melt the metal ,.
But i still have to be able to work extremely precisely in order to minimize damage to the semiconductor. And now the difficulty is that I have one second to get all fifty to one hundred thousand laser pulses exactly where I want to have the contacts. Several million solar cells have already been produced worldwide using the new Fraunhofer technology. This means the next evolutionary step in the silicon solar cell has already been made. The LaserFired Contact process is a very simple, lowcost process. This means that a highly efficient solar cell structure can be realized without substantial additional costs.