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Microwaving solar panels makes them easier to recycle

<div> <p><a href="https://cosmosmagazine.com/news/solar-cells-essential-for-brighter-future/" target="_blank" rel="noreferrer noopener">Solar cell</a> manufacturing and recycling should be easier with a surprising new discovery by Macquarie University scientists – that uses a commercial microwave.</p> <p>While they’re being made, the silicon in solar panels goes through a process called “annealing”, which involves heating the materials to temperatures well above 500°C.</p> <p>Annealing is usually done with ovens. But a study <a href="https://doi.org/10.1063/5.0127896" target="_blank" rel="noreferrer noopener">published</a> in Applied Physics Letters shows that microwaves are not only faster and more energy efficient for the job, but make the panels much easier to disassemble, and thus recycle, at the end of life.</p> <p>This is because microwave radiation heats individual substances – like the water in food, or silicon.</p> <p>“It just heats the very thin layer of silicon rather than heating the bulk of the materials around, and it’s really fast,” says lead author Dr Binesh Puthen Veettil, a researcher at Macquarie University’s School of Engineering.</p> <p>This also makes the process easier, because the microwave doesn’t have to be as carefully cleaned.</p> <p>“In most of the high temperature processes, lots of contaminants come out of the walls of the oven. But in this case, the heat is flowing from the silicon outwards, while everything else is at room temperature, it’s kind of a pseudo room temperature process where the contaminants don’t get diffused from outside,” says Veettil.</p> <p>“But the thing we are most excited about is the benefit to recycling.”</p> <p>Currently, solar cell recycling is a very <a href="https://cosmosmagazine.com/earth/sustainability/solar-panel-recycling/" target="_blank" rel="noreferrer noopener">energy intense process</a> which involves crushing up the panels and heating them to temperatures of at least 1000°C, so that all of the expensive elements can be extracted.</p> <p>This method destroys some of the reusable solar cell components: particularly, the toughened glass on the top of the panel.</p> <p>“This glass contains most of the weight of the solar panel,” explains Veettil.</p> <p>That glass is stuck to a layer of plastic, usually ethylene vinyl acetate, which keeps the silicon plate underneath dry. This plastic is too hard to remove, so the whole thing is smashed up, with the glass sold as scrap.</p> <p>But microwaving the silicon specifically softens the plastic, making it easy to peel.</p> <p>“You can just peel off the silicon cell, without destroying the glass, and you can reuse that expensive glass,” says Veettil.</p> <p>“If you can reuse the glass, the recycling will pay for itself.”</p> <p>Plus, it doesn’t need the same high temperatures, or extra chemicals needed to wash and dissolve the plastic.</p> <p>For now, the process is lab-based – and only for solar panels that fit in a commercial microwave.</p> <p>“Initially, when we started the research, we used a laboratory microwave that we purchased from a US company,” says Veettil.</p> <p>“And we after that, we purchased some kitchen microwaves locally, and modified it to suit our purposes.”</p> <p>This modification involved heat-proofing the microwave so that it could handle the annealing temperatures.</p> <p>“It goes from room temperature to 500° Celsius in just two seconds,” says Veettil. (Depending on the size of the sample: bigger things take longer.)</p> <p>But the researchers have a patent pending for the recycling process, and are now investigating how to improve and commercialise it.</p> <p>“We are hoping that with some industry collaboration and funding, we can scale it up,” says Veettil.</p> <p>“Recycling needs to be meet two conditions: it should be environmentally friendly, and second, it should pay for itself.</p> <p>“I’m pretty sure, with the numbers I have in mind, it will it will be profitable and then the market will take care of itself and it organically grow recycling centres. That’s my hope.”</p> </div> <div id="contributors"> <p><em>This article was originally published on <a href="https://cosmosmagazine.com/technology/microwaving-solar-panels-recycling/" target="_blank" rel="noopener">cosmosmagazine.com</a> and was written by Ellen Phiddian.</em></p> <p><em>Images: Getty</em></p> </div>

Technology

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Travelling around the globe might not have to cost the Earth

<p>The last time you booked a flight online, you may have been offered the chance to ‘offset’ the carbon produced by your travel. This is due in part to recognition that the aviation industry is responsible for around 5% of human-made emissions resulting in climate change.</p> <p>The efforts by this sector to respond to its environmental impact can range from switching fuels (from coal to biomass, for instance), more efficient combustion processes (by improving aircraft engines, for example), protecting forests or promoting sustainable development in local communities.</p> <p>Now, in a potentially ground-breaking innovation for long-haul flights, a team of researchers at the Swiss Federal Institute of Technology, Zürisch (ETH Zurich) have developed an all-in-one solar-powered tower that’s able to use energy from the Sun’s rays to convert water and carbon dioxide into synthetic fuels.</p> <p>Think: water + carbon dioxide = energy. Sound familiar? Well, it should. It’s what many plants do to make energy for themselves.</p> <p>The ETH Zurich process has a lot in common, really, explains Dr Jessica Allen, a chemical engineer and renewable energy technologies expert at the University of Newcastle. Although in this case, “industrial photosynthesis might be a better term as this particular process doesn’t involve any physiological mechanisms like plants and living material”, says Allen.</p> <p>The proof-of-concept solar tower consists of 169 Sun-tracking panels that reflect and concentrate sunlight into a tower-top solar reactor. Here, energy from the Sun’s rays meets a combination of water, carbon dioxide and a special structure made of ceria (cerium oxide), which is porous and “acts like a filter network, undergoing many reduction-oxidation (also known as redox) reactions”, says Allen.</p> <p>These reaction cycles produce syngas (synthesis gas), which is then converted to liquid fuels such as diesel and kerosene (which is used as jet fuel for long-haul flights) via a well-established process known as the Fischer-Tropsch reaction, which typically occurs in the presence of metal catalysts, temperatures of 150–300°C and pressures of several tens of atmospheres.</p> <p>Much work remains to translate the process to industrial scale. Currently, the energy efficiency of the process is only at 4%, meaning that out of 100 parts of energy available, only four parts are captured in the process. This is something the researchers are keen to push up towards around 15%.</p> <p>According to Allen, that’s still at the low end of the energy efficiency of current solar-to-electricity and solar-to-thermal energy generation. She says that efficiency is crucial when it comes to systems that use land area for solar collection (such as solar panels and the ETH Zurich tower’s reflectors): “A low efficiency will mean a large land area to generate the required fuel.”</p> <p>Where the CO2 comes from is also very important. At present, it’s injected into the system, but the next obvious step is to start capturing it directly from the air. At that point the fuel production process might be considered carbon neutral, as the amount of CO2 captured from the air is the same as the amount released during fuel combustion.</p> <p>Direct-from-air carbon dioxide capture comes at a cost, though. “There is a fairly major energy penalty for doing direct air capture, because it’s quite hard to filter out carbon dioxide from the rest of the gasses,” says Allen.</p> <p>Then there’s the carbon footprint related to the manufacture and production of equipment and materials, but Allen urges a long-term outlook: “In the system that we’re in at the moment there will be an emission penalty for the materials, however, in the long term, we’ll eventually be manufacturing these things using zero emission approaches.” This will make the whole process – and not just the fuel itself – carbon neutral.</p> <p>The average fuel consumption of a Boeing 747 (which are still used as long-haul cargo transport today) is around 4L per second. For a flight of 10 hours, this equates to 144,000L of fuel.</p> <p>In the future, EHT Zurich researchers will work to increase the system’s energy efficiency to 15%, capture more heat in the process and improve the ceria structures in the reactor in addition to capturing CO2 directly from the air. Their long-term aim is to scale the process to an industrial size – in which enough fuel can be produced to truly fly us into a carbon-neutral aviation future.</p> <p><em><strong>This article originally appeared on <a href="https://cosmosmagazine.com/science/carbon-neutral-travel-wont-cost-earth/" target="_blank" rel="noopener">cosmosmagazine.com</a> and was written by Clare Kenyon.</strong></em></p> <p><em>Image: Shutterstock</em></p>

Travel Trouble

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How to choose the best solar panels for your home

<p dir="ltr">The solar industry has seen a rapid growth over the past decade and become the cleanest, greenest and cheapest source of electricity.</p> <p dir="ltr">As electricity bills continue to rise at an exponential level, switching to solar makes sense. </p> <p dir="ltr">With many solar providers out there offering different services for widely differing costs, it's easy to get lost in the semantics of switching to solar. </p> <p dir="ltr">Luckily, Beau Savage, Co-Founder of <a href="https://smartenergy.co/au/">Smart Energy</a>, has shared his top tips to consider when finding the right solar provider for your home.</p> <p dir="ltr"><strong>Evaluate your home</strong></p> <p dir="ltr">The first step is to figure out if solar power is right for you. </p> <p dir="ltr">There are a few reasons why solar might not suit, including renters, apartment-dwellers, and anyone who lives in a shady spot might not be the ideal candidate for solar power.</p> <p dir="ltr">Luckily there are other ways to reduce your carbon footprint.</p> <p dir="ltr">“If conditions don’t suit, it might be better to invest in a 100 per cent carbon neutral energy plan,” says Beau.</p> <p dir="ltr"><strong>Do your research</strong></p> <p dir="ltr">Shopping for solar is no different to buying new furniture. </p> <p dir="ltr">It’s important to shop around for the best deal by looking at user reviews, comparing prices and services, and talking to experts before locking down a provider. </p> <p dir="ltr">Beau says, “The only negative reviews you want to see appearing on a good company should be from those who delayed getting and wished they’d done it sooner.”</p> <p dir="ltr"><strong>Find the right company</strong></p> <p dir="ltr">While there’s nothing wrong with prioritising affordability and cost comparison, be aware that low costs can occasionally translate to poor customer service and unreliable installers.</p> <p dir="ltr">According to Beau, “For the best long term results, choose a solar company who uses local installers so that if there is a problem, there will always be someone ready to immediately fix the issue.”</p> <p dir="ltr"><strong>Find the right spot</strong></p> <p dir="ltr">When it comes to solar power, location is key. </p> <p dir="ltr">The last thing you want is to discover that your installer has placed the panels in a bad spot, which only leads to more costs to correct the error. </p> <p dir="ltr">“When having an initial consultation it is essential to ask whether or not the company you are talking to sends trained engineers who can look at your roof, its shading and sunlight levels. This will ensure that you will get the most out of your solar system.”</p> <p dir="ltr">In order to get the most of your solar power, make sure there are no obstructions to your panels, and be sure to monitor the system’s performance to make sure you’re getting the very best green energy. </p> <p dir="ltr"><em>Image credits: Getty Images</em></p>

Home & Garden

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Solar curtailment is emerging as a new challenge to overcome as Australia dashes for rooftop solar

<p>Almost <a href="https://www.smh.com.au/environment/climate-change/australia-reaches-3-million-households-with-rooftop-solar-20211108-p59721.html">a third</a> of Australia’s estimated <a href="https://www.ibisworld.com/au/bed/number-of-households/31/">ten million households</a> now have solar on the roof. But as the nation moving fastest to produce energy on our homes, we are also encountering teething problems, such as “curtailment” of output.</p> <p>This issue will be one we have to overcome as ever more Australians install solar. Our grids were designed primarily for large fossil fuel power stations transmitting electricity in one direction, while solar households both consume and export power.</p> <p>That means in some conditions, household solar may contribute to spikes in voltage levels outside of the acceptable range, especially as voltage levels are typically already high.</p> <p>To counter this, your solar system can stop exporting to the grid or even shut down temporarily if voltage levels are too high. This is called “curtailment”.</p> <p><a href="https://images.theconversation.com/files/436513/original/file-20211209-21-qfm0ve.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip"><img src="https://images.theconversation.com/files/436513/original/file-20211209-21-qfm0ve.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip" alt="Solar technicians installing panels" /></a> <span class="caption">The rush for solar shows no signs of slowing – but curtailment could be a stumbling block.</span> <span class="attribution"><span class="source">Shutterstock</span></span></p> <h2>So what’s the issue?</h2> <p>The average solar household lose less than 1% of its power production to curtailment – and even less for those with home batteries. While that sounds minor, an unlucky few households are losing as much as 20%.</p> <p>Why the drastic difference? It depends on factors like the house’s location, the local electricity network equipment, home wiring, the number of solar systems in the area, and the size of a solar system and inverter settings, which can vary depending on the date of installation.</p> <p>These findings are from <a href="https://www.racefor2030.com.au/wp-content/uploads/2021/11/CANVAS-Succinct-Final-Report_11.11.21.pdf">our scoping study</a> in South Australia, conducted in partnership with AGL, SA Power Networks and Solar Analytics as part of the <a href="https://www.racefor2030.com.au/">RACE for 2030</a> research centre.</p> <p>We analysed two out of three modes of automatic curtailment, with further research underway to assess the third mode, which may account for greater overall curtailment.</p> <p>This issue is set to get bigger, as more and more solar systems are installed and export to the grid at the same time.</p> <p>Given the different ways solar households experience curtailment, this research also raises issues of fairness.</p> <p>Our research interviewed and ran focus groups with South Australians who have solar. We found most participants didn’t know about curtailment and hadn’t experienced it or noticed it.</p> <p>But when we described curtailment, most people found it off-putting and questioned whether rooftop solar owners should be made to absorb any losses, given the contribution of rooftop solar to the renewable energy transition.</p> <p>Not only that, our participants told us they believed the issue could slow down the adoption of solar and potentially undermine faith in the system.</p> <p><a href="https://images.theconversation.com/files/436514/original/file-20211209-19-azcfvo.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip"><img src="https://images.theconversation.com/files/436514/original/file-20211209-19-azcfvo.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip" alt="Power pylons" /></a> <span class="caption">Australia’s rapid renewable transition means challenges to overcome for the grid.</span> <span class="attribution"><span class="source">Shutterstock</span></span></p> <h2>Is this a problem for solar uptake?</h2> <p>The issue of curtailment means people may not get everything they expect out of their solar system. But this may not be a deal breaker, given <a href="https://ecss.energyconsumersaustralia.com.au/behaviour-survey-oct-2021/purchase-intentions/">earlier research</a> and our study both show that people hope to benefit in many different ways from installing a solar system.</p> <p>For instance, some want to reduce their reliance on fossil fuels and contribute to a cleaner grid. Others want to be less reliant on electricity providers and enjoy producing and using their own energy. And some just want cheaper electricity, and don’t mind whether they get these savings through selling their power or just buying less of what they need from the grid.</p> <p>The good news is that as the solar sector matures, new ways are emerging of maximising value from our solar, including:</p> <ul> <li>home energy management systems letting us time the use of appliances such as <a href="https://www.pv-magazine-australia.com/2021/09/06/unsw-study-channelling-rooftop-pv-into-water-heating-is-a-residential-super-saver/">hot water tanks</a> for daytime periods, when solar generates most power</li> <li>batteries letting us store power for use in the home when it is needed, such as in the evening</li> <li><a href="https://www.solarpowerworldonline.com/2017/09/virtual-power-plant/">virtual power plants</a> enabling households to be paid for allowing their solar and battery systems to help stabilise the electricity grid.</li> </ul> <p>While attractive in their own right, these options can also reduce how much your solar system is curtailed, and have the potential to help tackle challenges at a grid scale.</p> <p>Other changes to electricity and grid access and pricing could also help us better manage curtailment.</p> <p><a href="https://www.abc.net.au/news/2021-04-15/sa-power-networks-to-control-solar-exports-in-adelaide-trial/100070068">Flexible export limits</a> being trialled in South Australia and elsewhere would mean households could export electricity to the grid when it is needed, while occasionally being prevented from doing so when the network does not have capacity.</p> <p>Flexible export limits also mean households can install larger solar systems regardless of their location within the network. They could stop curtailment affecting solar households in unexpected and uneven ways.</p> <p>Other responses include <a href="https://discover.agl.com.au/solar/helping-to-maximise-your-solar-savings/">programs to reward households</a> for having their export curtailed, recognising it as a service to the market and the network.</p> <p>There is no single solution to the issue of curtailment. But the different solutions described above may contribute to the successful integration of more rooftop solar energy and pave the way for a more renewable grid.</p> <p>Now is the time to talk about the future of solar in Australia, and the ways we can value it, use it and manage it when abundant.<!-- Below is The Conversation's page counter tag. Please DO NOT REMOVE. --><img style="border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important; text-shadow: none !important;" src="https://counter.theconversation.com/content/172152/count.gif?distributor=republish-lightbox-basic" alt="The Conversation" width="1" height="1" /><!-- End of code. If you don't see any code above, please get new code from the Advanced tab after you click the republish button. The page counter does not collect any personal data. More info: https://theconversation.com/republishing-guidelines --></p> <p><span><a href="https://theconversation.com/profiles/sophie-adams-1203744">Sophie Adams</a>, Research Fellow, School of Humanities and Languages, <em><a href="https://theconversation.com/institutions/unsw-1414">UNSW</a></em>; <a href="https://theconversation.com/profiles/baran-yildiz-1259582">Baran Yildiz</a>, Senior Research Associate, <em><a href="https://theconversation.com/institutions/unsw-1414">UNSW</a></em>; <a href="https://theconversation.com/profiles/naomi-stringer-1296976">Naomi Stringer</a>, Research Associate, <em><a href="https://theconversation.com/institutions/unsw-1414">UNSW</a></em>, and <a href="https://theconversation.com/profiles/shanil-samarakoon-1295900">Shanil Samarakoon</a>, Lecturer, Centre for Social Impact, <em><a href="https://theconversation.com/institutions/unsw-1414">UNSW</a></em></span></p> <p>This article is republished from <a href="https://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/solar-curtailment-is-emerging-as-a-new-challenge-to-overcome-as-australia-dashes-for-rooftop-solar-172152">original article</a>.</p> <p><em>Image: Shutterstock</em></p>

Home Hints & Tips

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Beware the lure of unethical solar power

<div> <div class="copy"> <p>Solar energy may be the future. But only if it lets go of the past.</p> <p>International NGO the <a rel="noreferrer noopener" href="https://www.weforum.org/agenda/2021/09/to-lead-the-green-energy-future-solar-must-clean-up-its-supply-chains/" target="_blank">World Economic Forum</a> has issued a damning report card on the state of the world’s solar panel manufacturing. It may be experiencing rapid growth. It may be one of the cheapest sources of power. But its climate credentials face intense scrutiny.</p> <p>Forced labour, coal-fuelled production processes and a lack of transparency around the source of crucial components combine, the WEF says, into a cause for concern.</p> <p>“The solar industry is currently grappling with supply chain issues that could significantly impact its future,” the authors, professors Morgan Bazilian and Dustin Mulvaney, write.</p> <p>Much of their concern is concentrated on the production of polysilicon and the drive to make it cheap.</p> <p>Some 45% of global production of this component is sourced from Xinjiang province in China. And much of the labour force used to produce it is supplied by “re-education camps” detaining ethnic Kazakhs and Kyrgyz.</p> <p>On top of that, the remote desert region relies heavily on locally sourced coal for its power supply. “This attracted polysilicon manufacturers to this region of China in the first place because electricity is a major cost in the production process,” the report reads.</p> <p class="has-text-align-center"><strong><em>Read more: <a rel="noreferrer noopener" href="https://cosmosmagazine.com/technology/solar-and-wind-cheapest-energy-source-in-australia/" target="_blank">Solar and wind cheapest energy source in Australia</a></em></strong></p> <p>This, they say, undermines any climate and environmental benefits offered by solar panels further down the supply chain.</p> <p>“Solar panels are cheaper to build and install today in many places than alternative sources of electricity like coal and natural gas, translating to lower levels of greenhouse gases and air pollution,” they write.</p> <p>But Professor Alistair Sproul of the ANU’s School of Photovoltaic &amp; Renewable Energy Engineering says photovoltaic power has more than enough wiggle room in its pricing to clean up its act. Much of the price drop in photovoltaic (PV) production in recent years has been driven by advances in technology, particularly crystalline silicon, he says. “Even if the price stayed where it is now or went up a little – PV is very cost-competitive.”</p> <p>Under current life-cycle <a rel="noreferrer noopener" href="https://www.nrel.gov/analysis/life-cycle-assessment.html" target="_blank">calculations</a>, crystalline silicon PV cells produce about 50g of <span>CO<sub>2 </sub></span>for every kilowatt-hour of electricity. Black coal, in comparison, comes in at 1000g of <span>CO<sub>2</sub></span> per kWh.</p> <p>“The PV industry is growing each decade or so by a factor of 10 – this next decade is crucial – but as scale increases, costs will come down anyway – and the industry is not reliant on forced labour,” says Sproul.</p> <p>“Low-cost energy is really key here – so that there is a virtuous cycle – that as PV itself becomes cheaper it should be possible to lower the cost of producing PV further by utilising increasing amounts of PV electricity in manufacturing.”</p> <p>Sproul says materials that need coal for processing – especially steel – are all seeking alternatives.  “Hydrogen is definitely an avenue worth exploring as an alternative to coal to reduce iron oxide (for steel)  and silicon dioxide ( for silicon). [And] all supply chains need to be clear, transparent and free from forced labour.”</p> <em>Image credit: Shutterstock                         <!-- Start of tracking content syndication. Please do not remove this section as it allows us to keep track of republished articles --> <img id="cosmos-post-tracker" style="opacity: 0; height: 1px!important; width: 1px!important; border: 0!important; position: absolute!important; z-index: -1!important;" src="https://syndication.cosmosmagazine.com/?id=167605&amp;title=Beware+the+lure+of+unethical+solar+power" alt="" width="1" height="1" /> <!-- End of tracking content syndication -->          </em></div> <div id="contributors"> <p><em>This article was originally published on <a rel="noopener" href="https://cosmosmagazine.com/technology/energy/beware-the-lure-of-unethical-solar-power/" target="_blank">cosmosmagazine.com</a> and was written by Jamie Seidel. </em></p> </div> </div>

Technology

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Are you a frequent flyer? Solar storm radiation can be harmful

<p>Space weather <a href="https://theconversation.com/solar-eruption-could-help-earth-prepare-for-technology-melt-down-18747">impacts</a> many modern-day technologies. But one of the most concerning – and least reported – space weather effects is the increased radiation exposure to passengers on commercial long-distance flights during so-called “<a href="http://www.spaceweather.com/glossary/srs.html">solar radiation storms</a>”.</p> <p>The NASA-funded Nowcast of Atmospheric Ionizing Radiation System (<a href="http://sol.spacenvironment.net/~nairas/">NAIRAS</a>) is the computer system tasked with providing a real-time data-driven climatology of the aviation radiation environment.</p> <p>Recently, a series of papers published in the journal [Space Weather] estimate that when NAIRAS was turned off during the US government shutdown last year – which went into effect just as a solar radiation storm began – <a href="http://onlinelibrary.wiley.com/doi/10.1002/2013SW001015/abstract">500,000 people</a> received increased radiation doses.</p> <p>It has also been estimated that this event is likely to eventually result in four cancer-related deaths.</p> <p><strong>What is a solar radiation storm?</strong></p> <p>Disturbances on the surface of the sun are commonly the cause of geomagnetic disturbances here on Earth; such as power grid faults/failures and increased errors in GPS navigation and positioning.</p> <p>Associated with some of these solar disturbances is the ejection of extremely fast plasma into the solar wind that, when aimed directly towards the Earth, causes the onset of increased geomagnetic and ionospheric activity.</p> <p>The Earth-bound solar energetic particles ejected into the solar wind eventually penetrate into the Earth’s magnetosphere.</p> <p>When inside the magnetosphere, they orbit the planet across the Earth’s magnetic field lines until they are scattered by various complicated magnetospheric processes and interactions.</p> <p>Once scattered, these solar particles then travel down the magnetic field lines until they impact the Earth’s upper atmosphere, where they are effectively absorbed.</p> <p>The penetration depth of these particles primarily depends on their kinetic energy, which is governed by their mass and velocity.</p> <p>The less energetic particles are stopped by the Earth’s atmosphere typically between 100 and 400km altitude, causing the well-known <a href="http://spaceweathergallery.com/aurora_gallery.html">aurora</a> in the northern and southern high-latitude regions.</p> <p>The atmosphere increases in density exponentially as the particle falls. This normally prevents particles penetrating to lower altitudes where they are harmful to living organisms.</p> <p>The more energetic particles, called “solar energetic particles”, caused by these solar disturbances can <a href="http://www.dartmouth.edu/~barrel/index.html">penetrate</a> to below 10km, near of commercial flights.</p> <p>During such events, the danger posed by the increased radiation levels is easily averted by decreasing the cruising altitudes of the aircraft. Pilots can also divert their flight paths to areas less affected by the increased radiation levels (more equatorward latitudes).</p> <p><strong>Several chest X-rays worth of radiation</strong></p> <p>The aviation radiation monitoring performed in real-time by computer systems such as NAIRAS can effectively be used to issue such warnings to aircraft.</p> <p>This will help remove the threat posed to hundreds of thousands of people across the globe during such space weather events.</p> <p>The geomagnetic activity levels associated with the solar radiation storm that occurred during the US government shutdown were only minor (a minimum <a href="https://theconversation.com/solar-eruption-could-help-earth-prepare-for-technology-melt-down-18747">Dst</a> of -54nT).</p> <p>This means the technologies normally classified as being <a href="https://theconversation.com/divert-power-to-shields-the-solar-maximum-is-coming-11228">vulnerable</a> to extreme space weather events are not likely to have been significantly affected.</p> <p>The solar energetic particle levels observed by <a href="http://www.ngdc.noaa.gov/stp/satellite/goes/index.html">geostationary satellites</a> classifies this as an <a href="http://www.spaceweather.com/glossary/srs.html">S2</a>solar radiation storm. It lasted more than 24 hours, and took about four days to fully subside (see video below).</p> <p>Some controversy exists around the exact method used by the scientists of the first <a href="http://onlinelibrary.wiley.com/doi/10.1002/2013SW001015/abstract">study</a>into this event. There has been doubt around the estimation of the number of eventual cancer fatalities related to this solar radiation storm.</p> <p>Even though the radiation levels air travellers were exposed to during this event are much higher than they might have been had an appropriate warning been issued, they were still comparatively low – on par with the dose that one would receive from a number of chest X-rays.</p> <p>Arguments put forward by some <a href="http://onlinelibrary.wiley.com/doi/10.1002/2014SW001074/abstract">researchers</a> err on the side of caution. They indicate that some people who would be considered more vulnerable to increased radiation exposure (such as frequent flyers and unborn children) should have access to this radiation monitoring information.</p> <p>This would enable them to make educated decisions about appropriate air travel times in much the same way that non-urgent X-rays may be postponed during pregnancy.</p> <p><a href="http://onlinelibrary.wiley.com/doi/10.1002/2014SW001061/abstract">Other researchers</a> have erred on the opposite side, with the view that the radiation doses during this event were too small to be considered a serious threat.</p> <p>Independent of whether or not this particular space weather event exposed air travellers to dangerous levels of radiation, these studies are in clear agreement that increasing radiation monitoring is a must in the future.</p> <p>This is especially important for the aviation industry, and the provision of such information must not be hindered by short-term political partisan interests.</p> <p><em>Written by Brett Carter. Republished with permission of </em><a href="https://theconversation.com/are-you-a-frequent-flyer-solar-storm-radiation-can-be-harmful-28775"><em>The Conversation</em></a><em>.</em></p>

Travel Tips

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How to make sure your solar panel is worth it

<p>Customers who are planning to put solar power systems on their homes are being warned to make sure it makes financial sense first.</p> <p><strong>How does it work?</strong></p> <p>Solar panels are fitted on to a house, usually to the roof, positioned to capture as much sunshine as possible. They then generate power, which is fed back into the system.</p> <p>More expensive set-ups sometimes have batteries to hold the power that is generated. Vector is currently taking expressions of interest for a Tesla Energy battery that it will soon offer. These are expected to cost $7000 or more for the battery alone.</p> <p>A cheaper, and more common, option is a grid-tied system, where power is sold back to electricity suppliers if it is not used as it is generated.</p> <p><strong>Does a solar power system save money?</strong></p> <p>Whether you end up better off depends a lot on how you use your power.</p> <p>A good quality grid-tied system big enough to cater for a typical household costs about $12,000.</p> <p>Some power companies used to pay the same rate for solar power as they charged customers. That meant there were big savings to be made.</p> <p>But solar power specialist Phil Rumble, of Rumble Electrical, said there were ways to increase the benefits.</p> <p>He recommended customers make use of the timers on their appliances to set them to run when solar power was being generated.</p> <p>"On top of that you can get energy management systems that can range from a basic style that looks after your hot water to one that turns on and off your spa, fridge, underfloor heating… that can refine it down to using 70 per cent or 80 per  cent of your solar production."</p> <p><strong>What's changing?</strong></p> <p>The problem for the distribution networks in particular is that their pricing structures are not set up to cater for anyone who is generating their own electricity.</p> <p>Lines companies' costs are largely fixed but their charges are split between a daily fixed rate and a portion based on household energy consumption. When customers switch to solar, they cut this variable charge, even though they still require the infrastructure to get power to their houses for the times when solar is not providing.</p> <p>Do you have a solar panel?<br /> <br /> <em>Written by Susan Edmunds. First appeared on <a href="http://www.stuff.co.nz/" target="_blank"><strong><span style="text-decoration: underline;">Stuff.co.nz</span></strong></a>. </em></p>

Money & Banking

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NASA has made a discovery beyond our solar system

<p>For centuries, mankind has contemplated the mysteries of not only our solar system, but the entire universe. Now, it seems, we could be on the brink of a breakthrough.</p> <p>NASA have announced they will hold a news conference today (Wednesday 22) at 1pm EST (tomorrow 7am NZT) to present exciting new findings on exoplanets – that is, “planets that orbit stars other than our sun”.</p> <p>The nature of the discovery is not yet known, but due to the high-profile researchers due to attend the announcement, many are optimistic that it may concern extra-terrestrial life. These exoplanets are our main hope for life beyond our solar system, given their close resemblance to our own planet.</p> <p>Members of the public will be given the opportunity to speak directly to NASA scientists following the press conference, either on Twitter using the hashtag #AskNASA or during an AMA (“Ask me anything”) session on Reddit.</p> <p>Do you believe scientists will discover life beyond our solar system in our lifetime? Share your thoughts with us in the comments below.</p> <p><strong>Related links:</strong></p> <p><a href="/news/news/2017/02/qantas-introduces-dimmable-windows/"><span style="text-decoration: underline;"><em><strong>Qantas getting rid of window shutters</strong></em></span></a></p> <p><a href="/news/news/2017/02/monopoly-replaces-thimble-after-82-years/"><strong><span style="text-decoration: underline;"><em>Monopoly to replace the thimble after 82 years</em></span></strong></a></p> <p><a href="/news/news/2017/02/never-charge-phone-in-public-port/"><em><span style="text-decoration: underline;"><strong>Why you should never charge your phone in a public port</strong></span></em></a></p>

News

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A guide to generators and solar panels for your caravan or motorhome

<p>When you carry your hotel room behind you, in the form of a caravan, it can be nice to have your own power source on hand to keep you comfortable, no matter where you are. Not only does it help with things like cooking, climate control, and food storage, it can also free you up to stay just about anywhere.</p> <p>So let’s have a quick look at your options for generators and solar power systems when you’re on the road.</p> <p><strong>Generators</strong></p> <p>A 2000-watt generator is a great idea if you have a caravan or motorhome, as it will enable you to run lights, refrigeration, air conditioning, and some small cooking appliances. A five-litre generator should give you about 15 hours on Eco-throttle – a feature of many quality generators which adjusts the engine speed to meet load demand. A generator with Eco-throttle will have better fuel economy, and will run more quietly.</p> <p><strong>Solar Panels</strong></p> <p>Think of a solar panel like a battery charger by the sun’s rays. Most modern caravans and motorhomes are charged by the vehicle’s alternator while the engine is running, or by a battery charger when connected to 240V, which is great when you’re staying somewhere with mains power. When you’re not, however, your options are limited. And if you don’t want to put up with the noise pollution of running your engine or a noisy generator, solar panels can be an environmentally friendly, and very quiet alternative.</p> <p>You can find flexible solar panels these days, which are great for use on caravans, motorhomes, and even boats, as they are lightweight and easy to install.</p> <p><strong>Related links:</strong></p> <p><span style="text-decoration: underline;"><strong><em><a href="http://www.oversixty.co.nz/news/news/2015/12/abandoned-puppy-rescued-on-christmas-eve/">Abandoned puppy rescued on Christmas Eve doesn’t look like this anymore</a></em></strong></span></p> <p><span style="text-decoration: underline;"><strong><em><a href="http://www.oversixty.co.nz/news/news/2015/12/spot-the-cat-hidden-in-this-picture/">Can you spot the cat hidden in this picture?</a></em></strong></span></p> <p><span style="text-decoration: underline;"><strong><em><a href="http://www.oversixty.co.nz/news/news/2015/12/why-coffee-can-be-good-for-you/">Why giving up coffee could do you more harm than good</a></em></strong></span></p>

Domestic Travel

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5 ways to maximise your solar energy system

<p>You’ve done the research and made the big decision to get a solar energy system, but to ensure you get the most out of your system, here are five more things you should do.</p> <p><strong>1. Get professional installation</strong></p> <p>Installing your own panels can save you a lot of money but you should only do it yourself if you know what you’re doing! Installing solar panels incorrectly can cause a lack of energy absorption, meaning a costly venture in the long run if your panels are not working to their full potential.</p> <p><strong>2. Find the right place</strong></p> <p>Solar panels need to placed were they will receive the most sun exposure and tipped at an angle towards the sun. A professional installer will be able to help you decide on the best placement but be warned, sometimes the best position might not be the most aesthetically pleasing for the home.</p> <p><strong>3. Calculate your wattage</strong></p> <p>Before you decide on the number and size of panels needed, you need to calculate the amount of wattage you need. It’s best to do so in the times with the highest energy demands like in winter. This way you’ll be prepared and have sufficient energy year long.</p> <p><strong>4. Maintain your panels</strong></p> <p>To ensure your panels are in good shape year in year out, check them every year to ensure they are clean and secure. If your rooftop is prone to debris, check your panels more often and make sure to clear debris off panels as they need a direct exposure to the sun for maximum efficiency. Growing trees in your garden might need trimming to ensure there is sun access to the panels as well.</p> <p><strong>5. Reduce energy consumption</strong></p> <p>To get the best value from your solar energy system, as well as being environmentally friendly, your top priority should be reducing your power usage. There are many little actions you can take that collectively can make a big impact on your power bill. </p>

Home & Garden