Feed aggregator

A tale of two energy ministers is emerging in Canberra. The community is looking for politicians to champion renewables in the face of fossil fuel sector attacks on South Australia.

Microplastics can carry other pollutants. Oregon State University/Flickr, CC BY-SA

Up to 236,000 tonnes of microplastics – tiny pieces of broken-down plastic smaller than your little fingernail – enter our oceans each year. This has researchers around the world worried, as wildlife can be harmed by eating the plastic or by toxins attached to it.

Another concern is that these plastics and toxins could accumulate in food chains, eventually making their way into animals that eat ocean creatures – such as ourselves.

In two recent studies (one in Marine Biology and the other in Animal Behaviour) we found that microplastics can indeed be passed up the food chain to fish. But we also found some good news: the microplastics appeared to have no effect on their behaviour.

Sweat the small stuff

Microplastics are defined as particles less than 5mm across. A range of animals throughout the marine environment, including corals and zooplankton, consume these particles.

Once in the ocean, persistent toxic chemicals such as bisphenol A (BPAs) and pesticides stick to and accumulate on plastic particles, adding extra layers of contamination.

It is possible that the contaminants on microplastics are absorbed by animals and enter the food chain. If they don’t kill the animals, these toxic chemicals may affect the animals’ behaviour and hormone levels.

The way an animal behaves in its environment is crucial. Sometimes pollutants don’t cause obvious health issues but may alter the way an animal feeds, moves or socialises. Exposure to some chemicals, for example, causes feminisation in males, resulting in reduced breeding activity and ultimately affecting a population’s stability.

Even minor changes in behaviour can affect how an animal performs and may have longer-term implications for survival and reproduction. These changes in behaviour can be an early warning that something is going on, like the canary in the coal mine.

Hop to it

We wanted to know whether microplastics pass through the food web. Microplastics accumulate on beaches, so we assessed how coastal animals respond when they ingest microplastics.

We contaminated microplastics by immersing them in Sydney Harbour for two months and then fed them directly to beach hoppers, small jumping crustaceans at the bottom of the coastal food web.

We then fed the plastic-contaminated beach hoppers to gobies – small fish that commonly eat crustaceans like beach hoppers.

The beach hoppers readily ate microplastics as part of their diet. We found that after just three days the microplastics had accumulated in the beach hoppers. After five days microplastics had caused weight gain, a reduction in the hoppers’ ability to hop, and in some cases death.

But the fish, which we fed with contaminated beach hoppers for four weeks, showed no difference in behaviour compared to fish who weren’t fed plastic-filled hoppers. This was a surprising result, given that hormones (important drivers of behaviour) are so sensitive to pollutants.

Sink or swim

It is vital we understand how animals that are exposed to microplastics are affected.

Beach hoppers are primary consumers, crucial to decomposing seaweed. They play a key role in cycling nutrients back into the beach. They are also an important food source for birds, insects and fish, which makes the hoppers essential in moving energy up the food chain.

If microplastics harm beach hoppers, then the processes carried out by the hoppers may also be affected. This in turn could mean a change in essential coastal processes.

If beach hoppers can’t hop as far or as high, they may not not able to find shelter as quickly, putting them at risk of being eaten or of drying out in the exposed environments of sandy beaches. Fewer beach hoppers could mean less decomposition and nutrient recycling, as well as less food available for animals higher in the food chain.

Gobies are middle-sized predators that live in shallow waters and are important in the connectivity between coastal environments and the deeper ocean. Gobies are themselves eaten by larger fish and sea birds.

We know that fish behaviour can change following exposure to high levels of carbon dioxide and pharmaceuticals, but our study suggests that munching on beach hoppers full of microplastics has little effect.

These results challenge the paradigm that microplastics help contaminants accumulate in the food chain. A recent study suggests that contaminants obtained from the natural environment and prey far outweigh what is absorbed from ingested microplastics, which explains our result.

While this study suggests that microplastics may not be increasing contamination in an obvious manner, there is little doubt about their impact on animals that directly consume them. Perhaps impacts on behaviour will be more apparent with longer exposure times to contaminated food sources than those in our study.

After all, it can’t be a good thing that microplastics are so abundant in the oceans that they will leave an undeniable signature in the fossil record.

Jane Williamson does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article. She has previously received funding from the Australian Research Council for other projects.

Culum Brown and Louise Tosetto do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.

Electricity prices in NSW and Qld jump to nearly $13,000/MWh after gas plant fails, with coal-dependent Queensland to rely on rooftop solar and imports from NSW to meet heatwave demand.

While the Bureau of Meteorology is predicting an increase in the average temperature this summer, entomologists are forecasting an increase in insect activity.

It might seem that insects choose to annoy us over the summer, however, the real reason for their population boom is a complex interaction of winter rainfall, availability of food sources and increasing temperatures.

Insects are ectothermic, or “cold-blooded”, meaning their body temperature depends on the external environment. So in summer an increase in temperature typically correlates with an increase in insect activity.

Many insect species emerge from a winter resting phase in spring and summer to begin their winged adult life stages. These highly mobile, hungry, sex-obsessed young adults are the ones that interact with us over summer. Imagine schoolies’ week for insects, lasting an entire three months.

Rain leads to aphids

We all know that a decent rain can be great for our gardens. Last winter was the second wettest on record and rainfall was above average for most of Australia. This means not only did our backyard foliage and flowering plants do well, but so did common varieties of weeds. Common garden weeds around much of eastern and southern Australia include dandelions and sowthistle.

An increase in vegetation over the winter increases the breeding environment for aphids, and the population explodes. Aphids are sap-sucking true bugs (insect order Hemiptera) that can stunt tree growth, destroy flower buds and reduce the quality of fruit.

Most species, including the peach-potato aphid (Myzus persicae), lay eggs on plant stems, leaves and under bark during winter. These eggs hatch in spring or summer as temperatures and day lengths increase. Female aphids can produce 50 to 100 offspring in a very short period.

Natural pest management

Luckily our gardens already have a built-in defence system against aphid attack – flower flies. Flower flies, sometimes called hover flies, are a group of harmless wasp-mimicking flies (order Diptera, family Syrphidae) that you’ve probably noticed in your garden hovering above flowers, giving the flies their common name. They are found all over the world and include more than 6,000 species, 165 of which are unique to Australia.

While some flies, such as mosquitoes, bushflies and blowflies, will try and crash your summer party, most species, such as the flower flies, are busy eating pests in your garden for free. The natural food source of many flower fly larvae (also known as maggots) are nymph and adult aphids. Flower fly larvae eat a staggering number of aphids, potentially clearing a plant of these pests within a matter of hours.

Flower fly larvae eat aphids and are part of your gardens natural pest management.

Aphids spend their days sapping a plant of its fluids, including plant sugars. Consequently their excrement, known as honeydew, is quite sweet. Adult flower flies will seek out aphid honeydew to feed on and lay their eggs close by to ensure that their larvae will have a viable food source.

If you have ever noticed a swarm of adult hover flies resting on your car’s windshield or bonnet, you may have parked under a tree raining aphid honeydew. These flies are feeding on the honeydew stuck to your car.

Flies feeding on honeydew from a car parked under an aphid infested tree. CSIRO

Many other insect predators, such as ladybird larvae and adults, and lacewing larvae (known as aphid lions) are also feasting on the abundance of aphids in our gardens, competing with the flower fly larvae.

So there is quite a lot going on in your garden at this time of year. All of these predators are quite susceptible to insecticides and will be knocked out if you resort to spraying your aphids.

Insects gardening Australia

There are many benefits to having more insects in your garden and community. Many native Australian plants rely on insects for pollination, including a medley of hard working ants, bees, flies, wasps, beetles, butterflies, and moths.

Recent studies have shown that blowflies can carry twice as much pollen and have potential to out-pollinate the European honey bee. Soldier flies also do a fantastic job of turning your organic waste into compost.

So celebrate this summer by firing up the barbecue in the garden and embrace the Aussie salute! Live and let live is a good way to ensure that our natural pest control agents remain intact, although, keep some repellent on hand, just in case.

Bryan Lessard receives funding from the CSIRO and the Australian Biological Resources Study.

David Yeates receives funding from the CSIRO, the Australian Biological Resources Study, the US National Science Foundation, and holds the Schlinger endowed research position at the Australian National Insect Collection.

Malcolm Turnbull says ‘mechanisms’ to meet 2030 Paris emission reduction targets may need to be examined

Malcolm Turnbull has acknowledged the looming review of the Direct Action climate policy in 2017 “may result in some changes” to the federal renewable energy target.

The prime minister’s hedged observation on Thursday morning comes ahead of the release of the preliminary findings of the Finkel energy security review determining whether the national electricity market can deliver reliable base load power while meeting Australia’s climate change commitments.

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Europe’s research ministers are meeting to decide whether to try to land a robot rover on Mars.

For many households, the Powerwall 2 warranty is likely to last for under 9 years, rather than the full 10 years I was expecting.

A new joint venture has formed that will develop a high-power, EV fast-charging network in Europe has been signed by BMW, Daimler, Ford, VW.

Australia is now pretty much the only major advanced economy where carbon pollution levels are growing.

The CEFC and Investa have joined forces to push the boundaries of energy efficiency in commercial property.

Fish refuges are being created with environmental water in the Lachlan River to reduce the severity and duration of poor water quality being experienced in local waterways.

More than 24,000 Japanese businesses will now have access to COzero’s cloud-based energy management platform, EnergyLink, to save energy and costs.

Clean energy production on a historic site.

Variable speed limits, removal of speed bumps and ‘no idling’ zones near schools among recommendations

Speed bumps should be removed, speed limits made variable on England’s motorways, sometimes dropping as low as 50mph, and a congestion charge considered in more cities to cut air pollution and save lives, health experts have said.

The National Institute for Health and Care Excellence (Nice) released a series of recommendations on Thursday which it said would “promote a smoother driving style” and help keep emissions down.

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Greg Clark welcomes 700-job factory, the first to produce 75m-long blades for a new generation of offshore windfarms

The first 75-metre-long blades destined for windfarms off the UK’s coast will roll out of a factory in Hull when it officially opens on Thursday.

The inauguration of the Siemens plant at the city’s Alexandra Dock employs 700 people and was hailed by campaigners as an example of how curbing carbon emissions could create jobs.

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Victorian woman spends two days in hospital after being stung on neck off Fitzroy Island

A female snorkeller is lucky to be alive after suffering heart failure following an Irukandji jellyfish sting in far north Queensland.

The 39-year-old Victorian woman was snorkelling off Fitzroy Island last Friday when she was stung on the neck by the deadly, thumbnail-sized jellyfish.

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The Thylacine Awareness Group is ‘dedicated to the research, recognition and conservation of our most elusive apex predator’ – officially extinct since 1936

Six years ago Neil Waters moved to Tasmania. There, he says, he had a “brief encounter” with a thylacine, the carnivorous marsupial known as the Tasmanian tiger, declared extinct in 1986.

Two years later, in January 2014, he was doing work on his house when a smaller animal walked up a dirt track leading out of a tin mine and past his bedroom window.

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Major fault on Victorian transmission network separation of South Australia grid, power outages in South Australia for up to an hour, and disconnection of Portland smelter in Victoria.

Renewable energy poses a number of challenges for the grid. Wind turbine image from www.shutterstock.com

The Australian government is reviewing our electricity market to make sure it can provide secure and reliable power in a rapidly changing world. Faced with the rise of renewable energy and limits on carbon pollution, The Conversation has asked experts what kind of future awaits the grid.

Unreliable electricity supply can cause many inconveniences, such as the inability to check Facebook, being forced to play board games by candlelight in the evenings, and even, God forbid, missing out on a punt on the Melbourne Cup. But electricity blackouts have a more serious side too.

Findings from research overseas and in Australia show people are more likely to die during power outages. This is because of the increased risk of accidents, extreme cold or heat, food poisoning and communications breakdowns that can delay emergency responders.

So whatever our electricity grid looks like in the future, it will need to be reliable.

Meeting demand (most of the time)

Electricity demand varies during the day, so reliable electricity grids must be able to vary their output. Power supply needs to be constant and regular (this is known as “baseload power”) but also able to respond quickly to unexpected surges in demand (so-called “dispatchable power”). Finally, the grid must be responsive when extreme circumstances (such as storms or bushfires) affect supply.

Our current fossil-fuel-dominated electricity generation system is able to match supply with demand all but 0.002% of the time. It does this by relying largely on coal baseload power (64% of generation) which works together with other dispatchable power technologies – primarily gas (21%), as well as hydro (7%), oil (2%) and biomass (2%).

Generators in eastern Australia are also part of an interlinked transmission grid across New South Wales, South Australia, Victoria, Queensland, the Australian Capital Territory and Tasmania.

Variability in renewable resources (such sun and wind) is one of the main challenges to achieving the same reliability (or better) for a grid with more renewable energy generation.

There are several ways to manage this. First, there can be more generators than are required at any one point in time – power in one area can then be moved to areas that need it across a dispersed but highly interconnected transmission grid.

Second, we can avoid too much reliance on one particular technology (such as more than 30% wind). Having a mix of technologies provides a buffer.

Finally, we can include sufficient dispatchable energy sources or storage technologies. The list can include hydro, biomass, concentrated solar, geothermal, or batteries.

But herein lies the cost. Having more generators than needed at any point in time means that spare generators may sometimes sit idle.

Varying renewable resources also means that electricity may be produced but not purchased at times of low demand (and therefore wasted).

Buffering variable electricity supply would require an expansion of the transmission network across our vast continent to access our rich supply of renewable resources. But as distances increase, so do transmission losses.

So the question remains, at what cost would these strategies work?

The cost of reliability

Our recent research took a highly conservative approach to testing the cost question.

We assumed that there would be no future improvements in technology from what is currently viable and no future decrease in electricity demand. We also used renewable resource supply (sunshine and wind) from 2010 because this was one of the most challenging years for renewables.

Our findings indeed showed that strategies to manage the variability of renewable resources were effective in a 100% renewable energy mix of rooftop solar, wind, large-scale solar, hydro and biofuels.

In one scenario, for instance, current demand could be matched with supply at a cost of producing electricity around 20c per kilowatt hour (the current levelised cost of coal-fired electricity is 7.8-9.1c per kWh), with overall installed capacity of 162 gigawatts (2.5 to 3 times what is installed today), relatively low transmission losses and with less than 20% wasted electricity.

The interconnected eastern Australian transmission grid would need to be 2.5 times the current size, and would need to be linked to the grids in Western Australia and the Northern Territory.

Recent developments look positive for renewables

But recent developments mean that the costs and constraints for reliable renewable energy are not likely to be as conservative as our scenario.

Battery storage has benefited from rapid improvements in technology even in the short period since our research in 2015. Significant battery storage could even mean a restructuring of our largely centralised (big power stations) network to a more decentralised one that includes rooftop solar panels and battery storage.

Decentralisation of power generation opens up the possibility of using waste heat from power generation in buildings to reduce power demand (such as tri-generation).

Our research also indicates that investing in more dispatchable technologies can reduce wasted energy, the cost of energy, the grid expansion required, and overall generation capacity.

With the price of renewables decreasing, the transition to renewables may have benefits for power producers and power consumers.

Future constraints and opportunities for renewable energy are uncertain, but we can’t wait for perfect certainty before we plan and act. In Australia we have some of the world’s leading experts in the field with a range of sophisticated modelling capabilities at hand. These assets could be the foundation of collaboration with policymakers to transition to reliable renewable energy.

Bonnie McBain will be on hand for an Author Q&A from 2-3pm AEDT Thursday December 1. Leave your questions in the comments below.

Bonnie McBain does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.

Think of all the resources needed to transform Shenzhen, a fishing town 35 years ago, into a megacity of more than 10 million people. Wikimedia Commons, CC BY-SA

Cities are the epicentres of human activity. They cover less than 2% of the earth’s land surface but generate about 70% of GDP and house more than half the human population. The importance of cities is only going to increase in coming decades as another 2.5 billion people move to urban centres.

This intense production and consumption requires huge quantities of natural resources. Cities account for more than 60% of global energy use, 70% of greenhouse gas emissions and 70% of global waste. Current practices are depleting the Earth’s finite resources, changing its climate and damaging its natural ecosystems. With our planetary life support system in the red, we need to put cities on a serious resource diet.

Resources efficiency in the New Urban Agenda

The New Urban Agenda adopted at the Habitat III conference outlines a vision for sustainable urban development. These global guidelines, along with the related UN Sustainable Development Goals, recognise the need to use resources more efficiently.

Habitat III included a number of sessions on resource efficiency and associated tools and initiatives. Organisations such as UNEP, UN-Habitat and the European Commission and its research centres typically led these events. The New Urban Agenda includes many references to efficiency and reduced consumption in cities.

We must now act urgently to translate words into actions. This will ease pressure on ecosystems and produce a range of co-benefits, including health, wellbeing and resilience.

How do we create more resource-efficient cities?

Cities use resources directly, such as burning fossil fuels for electricity and transport. However, indirect uses, such as water for growing food crops, are much wider-reaching.

It can be overwhelming to consider the resources used for all goods, processes and infrastructure in cities. Yet it is possible to measure this using a systems approach. Instead of considering components in isolation, the entire city is considered as an open system, connected to others.

This perspective ensures a much broader understanding of complex relationships between scales, resource flows, the built environment, socio-economic factors and ecological outcomes.

There are tools that embrace a systems perspective. For example, the urban metabolism approach considers cities as ecosystems, across which flows of resources (such as energy or water) are measured. Life cycle assessment measures resource use through the entire production, consumption and degradation process of a good or service.

These approaches have been successfully applied at various scales such as cities, neighbourhoods and buildings. This reveals that we are using more resources than shown by traditional assessment techniques (see this example on building energy efficiency regulations).

But measurement without action has no impact on the ground. How can these tools be used to transform our cities?

Recent research enables us to map the quantities of materials in buildings and predict when and where we can reuse or recycle these. Here a map of estimated steel quantities in each building of Melbourne, Australia. Source: authors' own; left: Google and TerraMetrics; right: Stephan, A. and Athanassiadis, A. (In Press) Quantifying and mapping embodied environmental requirements of urban building stocks, Building and Environment

Many initiatives are targeting urban resource efficiency. The circular economy paradigm is a good example, where materials are reused, upcycled and recycled. It demonstrates that waste is a human concept and not an inherent property of cities. Waste does not exist in natural systems.

A range of projects by UNEP, the European Commission and other organisations support local resource efficiency initiatives and encourage local governments to implement related regulations. Blogging, data visualisation and disseminating research all help promote the adoption of resource efficiency concepts. In addition to the pioneering work of groups such as metabolism of cities, the uptake of open data is helping with this.

Learning from those who already live on less

Informal settlements provide interesting lessons in resource efficiency. Construction materials in these settlements are typically not very durable. However, because they are in short supply, they are constantly reused or repurposed, almost never discarded.

Other residents often reuse replaced materials, such as metal sheets, or store them for later use. This practice avoids additional resource use to produce new materials.

Although informal slum areas are often the focus of “upgrading” and improvement, lessons learnt in these settings can enhance material flow management and reduce waste elsewhere in cities.

Informal settlements like Karail next to Banani Lake in Dhaka, Bangladesh, can offer lessons in resource efficiency, waste reduction and material flow management to most cities. Alexei Trundle Co-benefits of resource efficiency

More resource-efficient cities tend to result in better health outcomes. For instance, encouraging walking, cycling and public transport instead of car use can reduce fossil fuel consumption and greenhouse gas emissions, and improve population health through increased physical activity.

Food systems that promote consumption of fresh, local produce can benefit both the environment and nutrition. Energy-efficient housing reduces energy and water use and can improve occupants’ health at the same time.

Resource efficiency can also contribute to urban resilience. Nature-based solutions use relatively few non-renewable materials to increase resilience to environmental change and natural disasters. For example, a park can be designed to be flooded during storms or a tsunami, reduce the urban heat island effect, support urban ecosystems and provide areas for community activities, recreation and urban agriculture.

Efficiency can also ensure that redundancy – a core principle of resilience – is built into urban systems. This means resources can be repurposed in the event of an unanticipated shock or stress. For example, during the recent blackout in South Australia, a household with solar battery storage was able to maintain power for 12 hours “off grid”.

Working together for better solutions

Although these steps move cities in the right direction, more action from governments, the private sector and civil society is needed to transform our growing urban footprints.

Focusing solely on resource efficiency may neglect opportunities to generate co-benefits across sectors and will not provide robust solutions. We need to look at the entire city as a system and work together, across all disciplines, with effective and strong governance structures that support integrated policy definition and long-term implementation. If we don’t, we might simply shift a problem from one area to another, increase resource demand elsewhere, or create social divisions and tensions.

Strong leadership, political stability, effective institutions and awareness-raising among citizens are vital factors for success. Urban resource efficiency is critical, but it should be considered along all other pressing issues highlighted in the New Urban Agenda.

André Stephan receives funding from the Australian Research Council.

Alexei Trundle receives research funding from the United Nations Human Settlements Programme (UN-Habitat), and an Australian Postgraduate Award from the Australian Government.

Dave Kendal receives funding from the Clean Air and Urban Landscape hub of the National Environmental Science Program

Hayley Henderson receives an APA scholarship from the Australian Government.

Hesam Kamalipour receives IPRS and APA scholarships from the Australian Government. He is also a Doctoral Academy member at the Melbourne Social Equity Institute (MSEI).

Melanie Lowe receives funding from the National Health and Medical Research Council and the National Environmental Science Programme.