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In the magical thinking of Australian policymakers, a pathway of gradual change, constructed over many decades in a growing, prosperous, coal-fired world stretches before us. But that's not the world that currently exists.

Could the new invention spell the end of rooftop fans? Christophe Finot/Wikimedia Commons, CC BY-SA

Specially designed fluid-filled roof panels can help make air conditioning significantly more efficient, according to new research.

These panels work like solar water heaters, except that they extract heat from the flowing fluid, rather than adding it. This has only been made possible through the development of new, highly reflective materials that allow more heat to be taken out of the fluid than finds its way back in, even in the heat of a sunny day.

Read more: How to keep your house cool in a heatwave.

As a result, the researchers, led by Eli Goldstein of Stanford University, calculate that these panels, when integrated into an existing air conditioning system, can use 20-50% less power to deliver the same amount of indoor cooling. This in turn could help smooth out demand peaks on the electricity grid in summer, cut energy bills, and reduce the risk of blackouts.

Cool research

For several years, the Stanford researchers and my own group at UTS in Sydney have been trying to design smart roof materials that will help dissipate heat from air conditioning systems more effectively.

Conventional air-conditioning systems get rid of their heat by simply venting hot air from the system’s outdoor fan unit. But the new design adds an extra step, using a heat exchanger to pass the normal refrigerant heat into the fluid, which can be either water or glycol. This fluid then flows into the rooftop cooling panels so the heat can be dissipated into the sky.

The old system and the new. Goldstein et al. Nature Energy

The previous problem with this approach was that on hot, sunny days – when you need air conditioning the most – the Sun makes the fluid-filled panels heat up, rather than cool down.

This problem has only been solved in the past three years, with the design of super-reflective surfaces that can repel 97% of the incoming solar energy.

Feeling the heat

Nearly all synthetic and natural surfaces absorb at least 5% of incident solar heat. Even the best white roof paints typically absorb more than 10% of the Sun’s heat. The best-performing surface is a shiny, flawless layer of silver, but that doesn’t last very long in outdoor conditions.

But what if we can protect the silver, and maybe even improve its reflective performance by placing it under a layer that also helps to reflect solar energy? Three research groups came up with possible solutions, two involving plastic coverings for the silver, and the third involving a complex layering of different oxide materials.

At UTS, our approach involved using many layers of two different plastics, placed on top of the silver. The resulting material reflects 97% of the incident solar energy, repelling the sun’s heat so effectively that the fluid inside cools down, even on a hot day.

Look to the skies

As the new Stanford research confirms, these super-reflective surfaces can perform a neat trick: getting the rooftop to lose heat during the day in the same way it does on a clear night. On clear nights, upward-facing surfaces can drop to several degrees below the ambient temperature because their heat dissipates high into the sky. The new super-cool roof panels do the same in the daytime as well. For example, they can condense dew well after sunrise even though the outdoor air temperature is above the dew point.

Read more: Air conditioning: we need to talk about indoor climate change.

The panels can easily be retrofitted onto existing air-conditioning systems, ultimately saving money in the long run because of the reduced energy use. By modelling their system’s performance, the Stanford researchers calculate that the panels could reduce air-conditioning costs by 21% for a typical two-storey building in the sunny climate of Las Vegas.

These kind of hybrid systems could become commonplace, combining existing indoor air-conditioning technology with the new panels shedding the heat directly upwards into the sky. If you’ll pardon the pun, things are really looking up for those aiming to bring their energy bills down.

Geoff Smith receives funding from Australian Research Council.

Company behind plans to develop Australia’s largest coal mine begins work on 170MW solar plant in another Queensland coal hub.

AEMO says its advice to the government was "pretty clear" and pragmatic: What the system needs is fast, flexible and reliable capacity to meet peak demand.

Pulborough Brooks, West Sussex One by one, the birds tip dramatically to one side, lowering one wing while raising the other, to lose height

The sharp honking sounds of geese echo across the Brooks. The air is clearing, but the rain still hangs over the low-lying hills in the distance, spreading down the sky like dark ink on wetted paper. As I walk out onto the marshes and towards the river Arun, the sun is rising behind me, spearing through the grey cloud.

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Scottish husband and wife team, aka Plug In Adventures, crossed Mongol Rally finish line on Saturday to become first entrants to complete the trans-continental challenge in an all-electric vehicle – a modified 2016 Nissan LEAF dubbed the AT-EV (All-Terrain Electric Vehicle).

Offshore wind now cheaper than nuclear and gas in UK, after second subsidy auction will see two developers build offshore wind farms for just $US75.83/MWh.

Alanna Mitchell is not a scientist, or an actor - but you can find her on stage in Sea Sick, detailing what's she's learned about the health of the world's oceans.

Electric cars set to get biggest boost ever, as China flags plans to stop making and selling traditional fuel cars "in the near future."

Culture wars: It may explain the continued efforts of some network operators to push back against the installation of more rooftop solar.

As national debate over energy supply reaches fever pitch, more attention is now being paid to the role of demand management, a weapon of last resort in Australia.

In a week where energy politics took centre state over market news, the most interesting development was the signing by retailer Flow Energy of a 10-year 50MW PPA with Ararat wind farm in Victoria. We have long seen that there is a need to develop th

Mosses are sensitive to even minor changes in their living conditions. Sharon Robinson, Author provided

Drones are helping scientists check the health of Antarctic mosses, revealing clues on the pace of climate change.

The scientists say their method could be used for similar research in other harsh environments like desert or alpine regions.

Mosses are sensitive to even minor changes in their living conditions, and scientists traditionally tramped through difficult terrain to collect data on them.

Using the specially-designed drones is faster, kinder to the environment and delivers detailed images that satellite imagery cannot match.

Drones also allow to map much larger areas than previously possible, showing how the moss health responds to meltwater in real time.

These methods could be used for similar research in other harsh environments like desert or alpine regions.

Zbyněk Malenovský has received grants from the ARC and Australian Antarctic Science. He is affiliated with the Surveying and Spatial Sciences Group at the University of Tasmania, the Centre for Sustainable Ecosystem Solutions at the University of Wollongong and the Global Change Research Institute at the Czech Academy of Sciences.

Arko Lucieer has received grants from the Australian Research Council and Australian Antarctic Science Grant Scheme.

A photographer wins a legal fight against an animal rights group over a "monkey selfie" photograph.

There has been no let up since Hurricane Harvey dumped record-breaking rains on the Houston area of Texas. Hurricane Irma lashed parts of the Caribbean and Cuba and is now heading onto the US mainland, having devastated the Florida Keys and the state’s west coast.

We also have Hurricane Jose following Irma through the Caribbean, and Hurricane Katia, now downgraded after tracking through parts of eastern Mexico.

Read more: Are catastrophic disasters striking more often?

This very active season comes after a “hurricane drought” with very few major storms making landfall on the US coast over the previous decade.

So why are we seeing so many hurricanes now? Is climate change to blame?

How to make a hurricane

There are several vital ingredients needed for hurricanes to form. These include an initial disturbance in the atmosphere for the storm to form around, very warm sea surface temperatures to sustain the storm, and a lack of vertical wind shear so the storm is not torn apart during its formation.

In the Atlantic Ocean, hurricanes often form near Cape Verde off the coast of West Africa. They then track westward towards the Caribbean and the US.

Lots of factors can affect how strong these storms ultimately become, including how much time they spend gathering strength over the ocean, and the background weather patterns through which they travel.

Sea surface temperatures are well above normal over the tropical Atlantic. The effects of Hurricane Harvey mixing up cooler waters off the Texan coast can be seen. NOAA Office of Satellite and Product Operations

This storm season we have seen sea temperatures persistently 1-2℃ above normal over the tropical Atlantic Ocean, which has allowed stronger storms to form and develop.

Atlantic sea temperatures have warmed over the past century, thus enhancing one of the key ingredients for hurricane formation. The climate change influence is clear for the sea temperatures, but not so much for the other ingredients required in forming hurricanes.

Harvey and Irma

While we have low confidence in the effect of human-caused climate change on hurricane formation, it is clear that climate change is enhancing some of the impacts of these storms.

Hurricane Harvey hit southern Texas hard by stalling over the Houston area and dumping huge amounts of rain. Climate change might have contributed to the stalling effect, but what’s clearer is that climate change is making intense extreme rainfall events like we saw over Houston more likely. By warming the atmosphere we’re also increasing its capacity to carry moisture.

When we have the trigger for heavy rainfall, climate change makes it rain harder.

Hurricane Irma is a very different beast to Harvey. It devastated several Caribbean islands including Anguilla and the Virgin Islands when it was a Category 5 system. It then struck Cuba before re-intensifying and moving north across the Florida Keys and onto the US mainland.

Irma’s main impacts have been through the storm surge, the strong winds and the heavy rains.

Climate change has likely worsened the effects of Irma. As described above, we know that climate change is intensifying extreme rain events. We also know that climate change is worsening storm surges by raising the background sea level on which these events occur.

Sea levels are projected to rise further over the coming century, by 50-100cm under a high greenhouse gas emissions scenario, and 20-50cm if we greatly reduce our emissions.

So while it’s likely that climate change is contributing to more extreme hurricanes, we have even more confidence that climate change is worsening the impacts of these storms, and will continue to do so over the coming decades.

Paving over the Gulf Coast

Besides the climate change influence, the widespread urban development on the US Gulf Coast is exacerbating the impacts of hurricanes.

Much like the Houston area, Florida also has a growing population. This means that not only are there more people in harm’s way when a major hurricane strikes, but there is also more concrete and other impervious surfaces that allow the water to pool in low-lying areas.

Is there any good news?

While climate change and development in hurricane-prone areas are worsening the impacts of these hurricanes, there are some glimmers of good news.

Scientists’ ability to track and forecast these major systems has improved greatly. Better forecasting of hurricanes allows for earlier planning for their impacts and should improve evacuation processes.

In theory, with the right plans in place, better hurricane forecasting should reduce death tolls from events like Irma. But it doesn’t necessarily reduce the economic costs of these storms, and for both Harvey and Irma the clean-up and recovery bills will be more than A$100 billion each.

It’s clear that climate has worsened the impacts of Atlantic hurricanes and will continue to do so. Improved forecasting provides a glimmer of hope that the death tolls from future events can be reduced, even as the economic impacts increase.

Andrew King receives funding from the ARC Centre of Excellence for Climate System Science.

Energy capacity auction shows offshore wind dramatically outstrips nuclear - and ministers must take note

Hinkley Point C nuclear power station was conceived in the days when offshore wind cost £150 per megawatt hour and a few misguided souls, some of them government ministers, thought a barrel of oil was heading towards $200.

Successive governments swallowed the line that Hinkley represented a plausible answer to the UK’s threefold energy conundrum – keeping the lights on, reducing carbon emissions and producing the juice at affordable prices for consumers and business.

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Joe Boyd is appealing to public for donations to challenge petrochemicals giant over ‘anti-democratic’ injunction

A second campaigner is challenging a sweeping injunction obtained by a petrochemicals giant against anti-fracking activists that has been criticised for profoundly limiting protests.

Joe Boyd, an anti-fracking campaigner, is going to the high court in London on Tuesday in an attempt to stop the injunction which has been secured by the multinational firm, Ineos. He is appealing to the public for donations as he could face a large bill if he loses.

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Ministers say culls are vital for cutting TB infections in cattle but scientists say there is little evidence to support the policy

Up to 33,500 badgers will be shot this autumn in an attempt to control tuberculosis in cattle, a huge rise from the 10,000 killed in 2016.

The government has announced that 11 new badger cull areas have been licensed, adding to the 10 already in place. Devon now has six badger culls under way, with Somerset and Wiltshire having three each, with others in Cheshire, Cornwall, Dorset, Gloucestershire and Herefordshire.

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A small great white shark was rescued after it was found floundering on a beach in Sydney, Australia, on Monday. The shark was found by beachgoers in shallow waters at Manly beach and was moved to a beach rockpool to be monitored by authorities

• Pool shark: beached great white given temporary refuge in Sydney rock pool
  

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Researchers and LGBT groups clash over facial recognition tech that supposedly spots gay people.