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Face of Orkney's St Magnus reconstructed
Microbead ban should include all products washed down the drain, say campaigners
A proposed government ban on the tiny plastic beads that pollute the ocean should be extended to include items such as make-up, sunscreen and cleaning products
Plans to ban tiny pieces of plastic that pollute the ocean should be extended to more products that people commonly wash down the drain, campaigners urged.
The government has proposed banning the sale and manufacture of products containing plastics known as microbeads that they classify as “rinse-off” items, such as shower gel, face scrubs and toothpaste.
Continue reading...Ancient undersea landslide discovered in Australia
Carmichael mine jobs need '212 times the subsidies' of renewables, says lobby group
Federal funding for Adani project amounts to $683,060 a job, compared with $3,219 a worker in Queensland’s clean energy sector, 350.org says
Clean energy projects in Queensland are already on track to create more employment than Australia’s largest proposed coalmine, which if funded federally would cost taxpayers 212 times more per job, according to new study.
Federal government agencies are investing $71.4m in seven solar farms and a wind farm in Queensland, which are set to deliver a total of 2,218 jobs, according to analysis by climate advocacy group 350.org.
Continue reading...There's nothing dull about dunnocks
Wenlock Edge With its riotous sex life and quick, edgy, movements, the hedge sparrow is like a little ticking bomb
Tseep! The hedge sparrow will not break loose from the gravity of the hedge. Hedge is home: a four-dimensional forest that travels through a landscape beset by dangerous space, and provides for a kind of dwelling that supports a very particular society. This tiny passerine is also called a dunnock – literally, little brown bird – an anonymous, blended-in, could-be-anything.
This one is prospecting for beetles, spiders and ants, as damp, mild, weather brings out early creatures. Its pencil-sharp beak shows that it is not adapted to seeds but it will take them when there’s nothing else. Drab and grey-headed is the usual description (as is mine), but there is a subtle vibrancy to its oak-polish brown flecked with darker encryptions, and its head, the colour of lichen on branches.
Continue reading...Sydney Airport achieves international Airport Carbon Accreditation recognition
Clean energy start-up accelerator program launches in Sydney
ABC accuses Labor of being “slave” to high renewables target
High energy prices? Blame fossil fuel generators, not renewables
Tesla, LG Chem tipped to dominate massive battery storage market
Victorian Coalition backs gas fracking ban – but not rooftop solar
Three renewable energy auctions to look out for
Crisis, what crisis? How smart solar can protect our vulnerable power grids
Report shows France will triple storage capacity by 2020
Do our ethical convictions need to go on holiday when we do?
Is it possible take an ethical holiday?
The late Hans Rosling tells the modern world's story
Endangered antelope 'may be wiped out'
Hans Rosling: Data visionary and educator dies aged 68
Crisis, what crisis? How smart solar can protect our vulnerable power grids
Some commentators seem to be worried that our electricity networks are facing an impending voltage crisis, citing fears that renewables (rooftop solar panels in particular) will threaten the quality of our power supply.
These concerns hinge on the fact that solar panels and other domestic generators can push up voltages, potentially making it harder for network companies to maintain stability across the grid. But what is less well understood (and far less reported) is the massive potential for local generation to actually improve the quality of our power, rather than hinder it.
A new report from our Networks Renewed project aims to show how technologies such as “smart inverters” can help to manage voltage at the household scale, rather than at substations. This would improve the quality of our power and flip the potential problem of household renewables into a solution.
Why all the fuss about voltage?Electricity from our power points should be at roughly 230 volts, without deviating too far above or below. It fluctuates throughout the day, depending on how much power is being used.
Here’s an analogy: think of water flowing through pipes. The power lines are the pipes themselves, and the voltage is like the water pressure in the pipes – that is, the amount of force pushing the water (or electricity) along. Using large amounts of power causes the voltage to drop, rather like when the washing machine comes on while you’re having a shower; all of a sudden the pressure drops because other appliances are using the water too.
Pressure is also affected by how close the appliance is to the source. For instance, if your washing machine and shower were connected right at the foot of the dam, instead of at the end of several miles of pipes, you could have them both switched on and not notice a drop in pressure.
For an electrical distribution system, this means that the houses farthest away from the substation are the most susceptible to sagging (lower) voltage when large amounts of power are being used.
Voltage management has always been an issue for grid operators, particularly in rural locations where the power lines are longer. Low voltage on long power lines often means dim and flickering lights for residents at the end of the line.
On the flip side, overvoltages can damage sensitive electronic equipment – a bit like when the water pressure pops your garden hose off the tap.
These fluctuations can become a problem for power companies when the voltage goes outside the allowable range.
How does solar power affect voltage?Our electricity networks were not originally built for lots of local generation sources like rooftop solar panels or small wind turbines. Until recently, power has generally flowed only in one direction, from a large (usually coal-fired) power station to consumers.
The growing number of household solar panels on the network have changed this landscape and now power flows both ways. Solar panels can make managing the grid more complex, because the voltage rises where they are generating power.
A small voltage increase is not a problem when there is enough demand for electricity. But when nobody is home in the neighbourhood, the solar power might lift the voltage beyond the upper limit.
In this case, the circuit protectors in the generator will probably trip and the solar panels will be cut off, to protect the network. This also means that the household won’t have access to (or get paid for!) the solar power it is generating.
Any customer-owned generator can affect the voltage – including solar, batteries, or diesel generators. But we tend to hear about solar because it is by far the most popular means of local generation; Australia now has more than 1.5 million homes with rooftop solar, and that figure is rising rapidly.
While some people might see this as an issue, sometimes the solution lies in the problem itself. In this case, new solar systems can offer a much more sophisticated way to manage grid voltage.
The innovation: smart inverters can control solar and batteries to help stabilise voltage on the grid. How can solar become the solution?Traditionally, voltage management solutions are fairly blunt, affecting tens or even hundreds of properties at a time, despite the fact that conditions might be quite different at each property. The equipment used – replete with technical-sounding names such as “on-load tap changers” and “line-drop compensators” – is expensive and is often located within transformers at substations. All of this electrical engineering kit adds to the cost of energy for customers.
However, new solar and battery systems now have the intelligence to manage voltage in a cheaper and more targeted way, through their “smart” inverters. These new technologies may provide the missing link to new renewable and reliable energy sources.
This is how it works: residential solar, batteries and other generators are connected to the grid through inverters that now have embedded IoT (internet of things) communications technology. These smart inverters allow the network to “talk” to the local generator and request support services, including through what’s called reactive power (see graphic below).
Reactive power can help to raise and lower the voltage on the network, improving the quality of our power including the voltage stability. For more technical detail see our newly released report on the potential for smart inverters to help manage the grid.
Smart inverters can export or absorb both real and reactive power.All this is only possible if network businesses are open to new, proactive ways of operating - as demonstrated by our Networks Renewed project partners United Energy in Victoria and Essential Energy in New South Wales.
This means a shift in thinking from the traditional passive customer model – we deliver energy to you! – to a more dynamic and collaborative one in which customers can actually help to manage the grid as well as using and generating power.
Sure, transitioning an entire energy system is no mean feat, but it offers an opportunity to build a better, more resilient electricity system that includes more renewable energy.
If we are smart, we will not need to trade off our climate impact with the dependability of our electricity system. We just need to be open to the new ways of solving old problems.
The Institute for Sustainable Futures (ISF) at the University of Technology Sydney undertakes paid sustainability research for a wide range of government, NGO and corporate clients, including energy businesses. The Networks Renewed project is funded by the Australian Renewable Energy Agency (ARENA) and the NSW and Victorian state governments, in partnership with Essential Energy, United Energy, Reposit Power, SMA Australia, and the Australian PV Institute. Lawrence McIntosh is also a partner at PV Lab Australia, a solar panel quality assurance business, and serves as the part time Principal Executive Officer of SolarShare, a community owned solar project in Canberra, ACT.
Dani Alexander is a member of the Institute for Sustainable Futures (ISF), which undertakes paid sustainability research for a wide range of government, NGO and corporate clients, including energy businesses.