How solar heat drives rapid melting of parts of Antarctica’s largest ice shelf

Scientists measured the thickness and basal melt of the Ross Ice Shelf.
Supplied, CC BY-ND

Craig Stewart, National Institute of Water and Atmospheric Research

The ocean that surrounds Antarctica plays a crucial role in regulating the mass balance of the continent’s ice cover. We now know that the thinning of ice that affects nearly a quarter of the West Antarctic Ice Sheet is clearly linked to the ocean.

The connection between the Southern Ocean and Antarctica’s ice sheet lies in ice shelves – massive slabs of glacial ice, many hundreds of metres thick, that float on the ocean. Ice shelves grind against coastlines and islands and buttress the outflow of grounded ice. When the ocean erodes ice shelves from below, this buttressing action is reduced.

While some ice shelves are thinning rapidly, others remain stable, and the key to understanding these differences lies within the hidden oceans beneath ice shelves. Our recently published research explores the ocean processes that drive melting of the world’s largest ice shelf. It shows that a frequently overlooked process is driving rapid melting of a key part of the shelf.

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Ocean fingerprints on ice sheet melt

Rapid ice loss from Antarctica is frequently linked to Circumpolar Deep Water (CDW). This relatively warm (+1C) and salty water mass, which is found at depths below 300 metres around Antarctica, can drive rapid melting. For example, in the south-east Pacific, along West Antarctica’s Amundsen Sea coast, CDW crosses the continental shelf in deep channels and enters ice shelf cavities, driving rapid melting and thinning.

Interestingly, not all ice shelves are melting quickly. The largest ice shelves, including the vast Ross and Filchner-Ronne ice shelves, appear close to equilibrium. They are largely isolated from CDW by the cold waters that surround them.

The satellite image shows that strong offshore winds drive sea ice away from the north-western Ross Ice Shelf, exposing the dark ocean surface. Solar heating warms the water enough to drive melting. Figure modified from https://www.nature.com/articles/s41561-019-0356-0.
Supplied, CC BY-ND

The contrasting effects of CDW and cold shelf waters, combined with their distribution, explain much of the variability in the melting we observe around Antarctica today. But despite ongoing efforts to probe the ice shelf cavities, these hidden seas remain among the least explored parts of Earth’s oceans.

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Climate scientists explore hidden ocean beneath Antarctica’s largest ice shelf

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It is within this context that our research explores a new and hard-won dataset of oceanographic observations and melt rates from the world’s largest ice shelf.

Beneath the Ross Ice Shelf

In 2011, we used a 260 metre deep borehole that had been melted through the north-western corner of the Ross Ice Shelf, seven kilometres from the open ocean, to deploy instruments that monitor ocean conditions and melt rates beneath the ice. The instruments remained in place for four years.

The observations showed that far from being a quiet back water, conditions beneath the ice shelf are constantly changing. Water temperature, salinity and currents follow a strong seasonal cycle, which suggests that warm surface water from north of the ice front is drawn southward into the cavity during summer.

Melt rates at the mooring site average 1.8 metres per year. While this rate is much lower than ice shelves impacted by warm CDW, it is ten times higher than the average rate for the Ross Ice Shelf. Strong seasonal variability in the melt rate suggests that this melting hotspot is linked to the summer inflow.

Summer sea surface temperature surrounding Antarctica (a) and in the Ross Sea (b) showing the strong seasonal warming within the Ross Sea polynya. Figure modified from https://www.nature.com/articles/s41561-019-0356-0.
Supplied, CC BY-ND

To assess the scale of this effect, we used a high-precision radar to map basal melt rates across a region of about 8,000 square kilometres around the mooring site. Careful observations at around 80 sites allowed us to measure the vertical movement of the ice base and internal layers within the ice shelf over a one-year interval. We could then determine how much of the thinning was caused by basal melting.

Melting was fastest near the ice front where we observed short-term melt rates of up to 15 centimetres per day – several orders of magnitude higher than the ice shelf average rate. Melt rates reduced with distance from the ice front, but rapid melting extended far beyond the mooring site. Melting from the survey region accounted for some 20% of the total from the entire ice shelf.

The bigger picture

Why is this region of the shelf melting so much more quickly than elsewhere? As is so often the case in the ocean, it appears that winds play a key role.

During winter and spring, strong katabatic winds sweep across the western Ross Ice Shelf and drive sea ice from the coast. This leads to the formation of an area that is free of sea ice, a polynya, where the ocean is exposed to the atmosphere. During winter, this area of open ocean cools rapidly and sea ice grows. But during spring and summer, the dark ocean surface absorbs heat from the sun and warms, forming a warm surface pool with enough heat to drive the observed melting.

Although the melt rates we observe are far lower than those seen on ice shelves influenced by CDW, the observations suggest that for the Ross Ice Shelf, surface heat is important.

Given this heat is closely linked to surface climate, it is likely that the predicted reductions in sea ice within the coming century will increase basal melt rates. While the rapid melting we observed is currently balanced by ice inflow, glacier models show that this is a structurally critical region where the ice shelf is pinned against Ross Island. Any increase in melt rates could reduce buttressing from Ross Island, increasing the discharge of land-based ice, and ultimately add to sea levels.

While there is still much to learn about these processes, and further surprises are certain, one thing is clear. The ocean plays a key role in the dynamics of Antarctica’s ice sheet and to understand the stability of the ice sheet we must look to the ocean.

Craig Stewart, Marine Physicist, National Institute of Water and Atmospheric Research

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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New solar cells offer you the chance to print out solar panels and stick them on your roof

This roof in Newcastle has become the first in Australia to be covered with specially printed solar cells.
University of Newcastle, Author provided

Paul Dastoor, University of Newcastle

Australia’s first commercial installation of printed solar cells, made using specialised semiconducting inks and printed using a conventional reel-to-reel printer, has been installed on a factory roof in Newcastle.

The 200 square metre array was installed in just one day by a team of five people. No other energy solution is as lightweight, as quick to manufacture, or as easy to install on this scale.

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Our research team manufactured the solar modules using standard printing techniques; in fact, the machine that we use typically makes wine labels. Each solar cell consists of several individual layers printed on top of each other, which are then connected in series to form a bank of cells. These cells are then connected in parallel to form a solar module.

Since 1996, we have progressed from making tiny, millimetre-sized solar cells to the first commercial installation. In the latest installation each module is ten metres long and sandwiched between two layers of recyclable plastic.

At the core of the technology are the specialised semiconducting polymer-based inks that we have developed. This group of materials has fundamentally altered our ability to build electronic devices; replacing hard, rigid, glass-like materials such as silicon with flexible inks and paints that can be printed or coated over vast areas at extremely low cost.

As a result, these modules cost less than A$10 per square metre when manufactured at scale. This means it would take only 2-3 years to become cost-competitive with other technologies, even at efficiencies of only 2-3%.

These printed solar modules could conceivably be installed onto any roof or structure using simple adhesive tape and connected to wires using simple press-studs. The new installation at Newcastle is an important milestone on the path towards commercialisation of the technology – we will spend the next six months testing its performance and durability before removing and recycling the materials.

The solar cells can be installed with little more than sticky tape.
University of Newcastle, Author provided

We think this technology has enormous potential. Obviously our technology is still at the trial stage, but our vision is a world in which every building in every city in every country has printed solar cells generating low-cost sustainable energy for everyone. This latest installation has brought the goal of solar roofs, walls and windows a step closer.

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Ultimately, we imagine that these solar cells could even benefit those people who don’t own or have access to roof space. People who live in apartment complexes, for example, could potentially sign up to a plan that lets them pay to access the power generated by cells installed by the building’s owner or body corporate, and need never necessarily “own” the infrastructure outright.

But in a fractured and uncertain energy policy landscape, this new technology is a clear illustration of the value of taking power into one’s own hands.

Paul Dastoor, Professor, School of Mathematical and Physical Sciences, University of Newcastle

This article was originally published on The Conversation. Read the original article.

What’s wrong with big solar in cities? Nothing, if it’s done right

Residents near big solar projects are often concerned they cause glare and noise.
Electrical and Mechanical Services Department Headquarters rooftop solar, Hong Kong/Wikimedia Commons

Jason Byrne, University of Tasmania

Many of us are familiar with developments of big solar farms in rural and regional areas. These are often welcomed as a positive sign of our transition towards a low-carbon economy. But do large-scale solar installations have a place in our cities?

The City of Fremantle in Western Australia is considering a proposal to use a former landfill site for a large-scale solar farm. The reportedly 4.9 megawatt solar power station on an eight-hectare site would be, it’s said, Australia’s largest urban solar farm. The initiative is part of Fremantle’s ambition to be powered by 100% clean energy within a decade.

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Solar is now the most popular form of new electricity generation worldwide

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The proposal is facing some community opposition, however. Residents are reportedly alarmed by the potential public health consequences of building on a rubbish dump, which risks releasing toxic contaminants such as asbestos into the environment. Other concerns include glare from the solar panels, or excessive noise.

Similar complaints about solar panels in cities are being seen all over the world, with opponents generally of the view “they do not belong in residential areas”. So what are the planning issues associated with large-scale solar installations in cities? And should we be concerned about possible negative impacts?

What is large-scale solar?

According to the Australian Clean Energy Regulator, large-scale solar refers to “a device with a kilowatt (kW) rating of more than 100 kilowatts”. A kilowatt is a measure of power – the rate of energy delivery at a given moment – whereas a kilowatt-hour (kWh) is a measure of the total energy produced (so a 100kW device operating for one hour would produce 100kWh of electricity).

Device here refers to not only the photovoltaic (PV) panels – the actual panels used in solar energy – but also to the infrastructure “behind the electricity meter”. So interconnected panels may still constitute a single device.

By this definition, there may already be large-scale solar installations in Australian cities. In Sydney for example, the recently opened system on top of the Alexandra Canal Transport Depot is by all accounts a large-scale solar system. It combines around 1,600 solar panels with enough battery storage for 500kWh of electricity.

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But this is not Sydney’s largest solar installation. That honour is presently held by the Sydney Markets in Flemington, among Australia’s largest rooftop solar installations, which generates around 3 megawatts (that’s 3,000kW). To date, there have been no publicly disclosed complaints received about these facilities.

Large-scale solar (sometimes called “big solar”) can also refer to solar arrays that use mirrors to concentrate sunlight onto solar PV panels. This is different to concentrated thermal solar, which uses mirrors to focus sunlight onto the top of a tower to heat salt, oil or other materials that can then be used to generate steam to power turbines for electricity generation.

What’s the problem with solar in cities?

Internationally, there is increasing recognition cities could be ideal locations for large-scale solar installations due to the amounts of unused land. This includes land alongside freeways and main roads, flood-prone land, and rooftops on factories, warehouses and residences. And locating big solar in cities can also reduce the energy losses that occur with transmitting electricity over long distances.

Australia’s combined rooftop solar installations already supply the equivalent of enough power for all the homes in Sydney. And even former landfill sites – which have few uses other than parkland and are often too contaminated to sustain other land uses such as residential development – can be a good use of space for solar farms. But such sites would need to be carefully managed so contaminants are not released during construction.

Large-scale solar installations can present some challenges for urban planning. For instance, mirrors can cause problems with glare, or even damage if they were misaligned (problems thus far have been in solar thermal plants). Maintenance vehicles may increase traffic in neighbourhoods. Installing solar panels could cause temporary problems with noise and lighting. And views could potentially be disrupted if adjoining residents overlook a large-scale solar installation.

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But not all of these impacts would be long-term, and they can all potentially be managed through planning approval, permitting processes and development conditions. Installing screens or trees can improve views, for instance. Glare is a potential problem but again can be managed via screening (at the site or on overlooking buildings) or protective films on the panels.

The issue with the proposed solar farm in Fremantle is the fact it’s planned atop a former landfill site, known to contain harmful substances including asbestos, hydrocarbons and heavy metals. Unless carefully managed, construction of the solar farm could disturb these materials and potentially expose nearby residents to health impacts.

Most state environmental protection agencies recognise risks if the use of potentially contaminated land is to be changed, and have developed stringent guidelines for landfill management.

The Algarve Lagos solar farm in Portugal shows how empty land in cities can be used to host energy efficiency platforms.
Wikimedia Commons

The City of Fremantle has approved the proposed development, subject to the preparation of a site management plan among other conditions. Depending on site management, and the characteristics of surrounding neighbourhoods, poorly managed big solar on landfill sites could become an environmental justice issue. From this perspective, residents’ concerns are understandable, and the City of Fremantle will need to ensure it carefully monitors construction.

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Lessons for planning

It is reasonable to expect that cities will increasingly host large-scale solar installations. With careful site selection and management, the multiple benefits of clean energy can accrue to urban residents. Otherwise leftover or marginal land can derive an economic return.

Of course care will need to be taken to minimise potential habitat loss or off site impacts such as visual intrusion, noise, and glare. But solar farms also have the potential to provide new habitats both via physical infrastructure (sites for nesting) and as part of site rehabilitation and management.

Jason Byrne, Professor of Human Geography and Planning, University of Tasmania

This article was originally published on The Conversation. Read the original article.

Policy overload: why the ACCC says household solar subsidies should be abolished

Lucy Percival, Grattan Institute

The keenly awaited report on retail electricity prices, released this week by the Australian Competition and Consumer Commission (ACCC), has made some controversial recommendations – not least the call to wind up the scheme that offers incentives for household solar nearly ten years early.

The report recommends that the small-scale renewable energy scheme (SRES) should be abolished by 2021. It also calls on state governments to fund solar feed-in tariffs through their budgets, rather than through consumers’ energy bills.

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The ACCC has concluded that offering subsidies for household solar was a well-intentioned but ultimately misguided policy. Solar schemes were too generous, unfairly disadvantaged lower-income households, and failed to adjust to the changing economics of household solar.

The lesson for policy-makers is that good policy must keep costs down as Australia navigates the transition to a low-emissions economy in the future. Failure to do this risks losing the support of consumers and voters.

Runaway rebates

Rooftop solar schemes were much more popular than anticipated. This might sound like the sign of a good policy. But in reality it was more like designing a car with an accelerator but no brakes.

Generous feed-in tariffs and falling small-scale solar installation costs encouraged more households to install solar than were initially expected. Premium feed-in tariffs were well above what generators were paid for their electricity production. Historically solar feed-in tariffs paid households were between 16c and 60c per kilowatt-hour, while wholesale prices were less than 5c per kWh.

At the same time, installation costs for solar panels fell from around A$18,000 for a 1.5kW system in 2007, to around A$5,000 for a 3kW system today. The SRES subsidy for solar installations was not linked to the actual installation cost or the cost above the break-even price. So the SRES became relatively more generous as installation costs fell.

As solar penetration increased, and network costs rose to cover this, it became increasingly attractive for households to install solar panels. In Queensland, the initial cost forecast for the solar bonus scheme was A$15 million. Actual payments were more than 20 times that in 2014-15, at A$319 million. And the environmental benefits weren’t big enough to justify that cost, as other policies have reduced emissions at a lower cost. The large-scale renewable energy target reduced emissions for A$32 per tonne, while household solar panels reduced emissions at a cost of more than A$175 per tonne.

In most states, premium feed-in tariffs and rooftop solar subsidies are funded through higher bills for all consumers. Everyone pays the costs, yet only those with panels receive the benefits. That means the costs fall disproportionately on lower-income households and those who rent rather than own their home.

The ACCC report recommends the SRES be wound up nearly 10 years ahead of schedule, because the subsidies are no longer financially justifiable. This would maintain the support for current solar installations but remove subsidies for new solar installations from 2021.

The report also recommends removing the direct costs of feed-in tariffs from electricity bills. Instead, state governments should directly cover the costs of premium feed-in tariffs. The Queensland government has already made this move.

Of course, governments still have to find the money from elsewhere in their revenues, which means taxpayers are still footing the bill. But the new arrangement would at least remove the current unfair burden on households without solar.

Fixing the mistakes

How can governments avoid making similar policy mistakes in the future? The ACCC’s recommendations, together with the proposed National Energy Guarantee (NEG), provide a solid foundation for Australia’s future energy policy.

First, the future is hard to predict, so good policy adapts to change. The NEG provides a flexible framework to direct energy policy towards a low-emission, high-reliability, low-cost future. Reviewing and adjusting the emissions target along the way will enable Australia’s energy policy to respond to new technologies and shifting cost structures, while maintaining consistency with economy-wide targets.

Second, it is hard to pick winners, so good policy creates clear market signals. The NEG provides the energy industry with clear expectations, but is technology-agnostic and minimises government intervention. This encourages the market to find the most cost-effective way to reduce emissions and ensure reliability.

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The ACCC report also recommends simplifying retail electricity offers, which would make it easier for consumers to find a good deal, and in turn making the market more competitive.

Politicians have an opportunity to draw a line in the sand on narrow, technology-specific policies such the SRES. An integrated energy and climate policy should focus on good design, and then step back and let the market pick the winners.

Lucy Percival, Associate, Grattan Institute

This article was originally published on The Conversation. Read the original article.

Solar is now the most popular form of new electricity generation worldwide

Andrew Blakers, Australian National University

Solar has become the world’s favourite new type of electricity generation, according to global data showing that more solar photovoltaic (PV) capacity is being installed than any other generation technology.

Worldwide, some 73 gigawatts of net new solar PV capacity was installed in 2016. Wind energy came in second place (55GW), with coal relegated to third (52GW), followed by gas (37GW) and hydro (28GW).

https://datawrapper.dwcdn.net/tCtqa/1/

Together, PV and wind represent 5.5% of current energy generation (as at the end of 2016), but crucially they constituted almost half of all net new generation capacity installed worldwide during last year.

It is probable that construction of new coal power stations will decline, possibly quite rapidly, because PV and wind are now cost-competitive almost everywhere.

Hydro is still important in developing countries that still have rivers to dam. Meanwhile, other low-emission technologies such as nuclear, bio-energy, solar thermal and geothermal have small market shares.

PV and wind now have such large advantages in terms of cost, production scale and supply chains that it is difficult to see any other low-emissions technology challenging them within the next decade or so.

That is certainly the case in Australia, where PV and wind comprise virtually all new generation capacity, and where solar PV capacity is set to reach 12GW by 2020. Wind and solar PV are being installed at a combined rate of about 3GW per year, driven largely by the federal government’s Renewable Energy Target (RET).

This is double to triple the rate of recent years, and a welcome return to growth after several years of subdued activity due to political uncertainty over the RET.

If this rate is maintained, then by 2030 more than half of Australian electricity will come from renewable energy and Australia will have met its pledge under the Paris climate agreement purely through emissions savings within the electricity industry.

To take the idea further, if Australia were to double the current combined PV and wind installation rate to 6GW per year, it would reach 100% renewable electricity in about 2033. Modelling by my research group suggests that this would not be difficult, given that these technologies are now cheaper than electricity from new-build coal and gas.

Renewable future in reach

The prescription for an affordable, stable and achievable 100% renewable electricity grid is relatively straightforward:

1. Use mainly PV and wind. These technologies are cheaper than other low-emission technologies, and Australia has plenty of sunshine and wind, which is why these technologies have already been widely deployed. This means that, compared with other renewables, they have more reliable price projections, and avoid the need for heroic assumptions about the success of more speculative clean energy options.

2. Distribute generation over a very large area. Spreading wind and PV facilities over wide areas – say a million square kilometres from north Queensland to Tasmania – allows access to a wide range of different weather, and also helps to smooth out peaks in users’ demand.

3. Build interconnectors. Link up the wide-ranging network of PV and wind with high-voltage power lines of the type already used to move electricity between states.

4. Add storage. Storage can help match up energy generation with demand patterns. The cheapest option is pumped hydro energy storage (PHES), with support from batteries and demand management.

Australia currently has three PHES systems – Tumut 3, Kangaroo Valley, and Wivenhoe – all of which are on rivers. But there is a vast number of potential off-river sites.

Potential sites for pumped hydro storage in Queensland, alongside development sites for solar PV (yellow) and wind energy (green). Galilee Basin coal prospects are shown in black.
Andrew Blakers/Margaret Blakers, Author provided

In a project funded by the Australian Renewable Energy Agency, we have identified about 5,000 sites in South Australia, Queensland, Tasmania, the Canberra district, and the Alice Springs district that are potentially suitable for pumped hydro storage.

Each of these sites has between 7 and 1,000 times the storage potential of the Tesla battery currently being installed to support the South Australian grid. What’s more, pumped hydro has a lifetime of 50 years, compared with 8-15 years for batteries.

Importantly, most of the prospective PHES sites are located near where people live and where new PV and wind farms are being constructed.

Once the search for sites in New South Wales, Victoria and Western Australia is complete, we expect to uncover 70-100 times more PHES energy storage potential than required to support a 100% renewable electricity grid in Australia.

Potential PHES upper reservoir sites east of Port Augusta, South Australia. The lower reservoirs would be at the western foot of the hills (bottom of the image).
Google Earth/ANU

Managing the grid

Fossil fuel generators currently provide another service to the grid, besides just generating electricity. They help to balance supply and demand, on timescales down to seconds, through the “inertial energy” stored in their heavy spinning generators.

But in the future this service can be performed by similar generators used in pumped hydro systems. And supply and demand can also be matched with the help of fast-response batteries, demand management, and “synthetic inertia” from PV and wind farms.

Wind and PV are delivering ever tougher competition for gas throughout the energy market. The price of large-scale wind and PV in 2016 was A$65-78 per megawatt hour. This is below the current wholesale price of electricity in the National Electricity Market.

Abundant anecdotal evidence suggests that wind and PV energy price has fallen to A$60-70 per MWh this year as the industry takes off. Prices are likely to dip below A$50 per MWh within a few years, to match current international benchmark prices. Thus, the net cost of moving to a 100% renewable electricity system over the next 15 years is zero compared with continuing to build and maintain facilities for the current fossil-fuelled system.

Gas can no longer compete with wind and PV for delivery of electricity. Electric heat pumps are driving gas out of water and space heating. Even for delivery of high-temperature heat for industry, gas must cost less than A$10 per gigajoule to compete with electric furnaces powered by wind and PV power costing A$50 per MWh.

Importantly, the more that low-cost PV and wind is deployed in the current high-cost electricity environment, the more they will reduce prices.

Then there is the issue of other types of energy use besides electricity – such as transport, heating, and industry. The cheapest way to make these energy sources green is to electrify virtually everything, and then plug them into an electricity grid powered by renewables.

A 55% reduction in Australian greenhouse gas emissions can be achieved by conversion of the electricity grid to renewables, together with mass adoption of electric vehicles for land transport and electric heat pumps for heating and cooling. Beyond this, we can develop renewable electric-driven pathways to manufacture hydrocarbon-based fuels and chemicals, primarily through electrolysis of water to obtain hydrogen and carbon capture from the atmosphere, to achieve an 83% reduction in emissions (with the residual 17% of emissions coming mainly from agriculture and land clearing).

Doing all of this would mean tripling the amount of electricity we produce, according to my research group’s preliminary estimate.

But there is no shortage of solar and wind energy to achieve this, and prices are rapidly falling. We can build a clean energy future at modest cost if we want to.

Andrew Blakers, Professor of Engineering, Australian National University

This article was originally published on The Conversation. Read the original article.

Get in on the ground floor: how apartments can join the solar boom

Getting your strata committee to agree to solar panels is tricky, but it can be done.
Stucco, Author provided

Bjorn Sturmberg, Macquarie University

While there are now more solar panels in Australia than people, the many Australians who live in apartments have largely been locked out of this solar revolution by a minefield of red tape and potentially uninformed strata committees.

In the face of these challenges, Stucco, a small co-operative housing block in Sydney, embarked on a mission to take back the power. Hopefully their experiences can serve as a guide to how other apartment-dwellers can more readily go solar.

From an energy perspective, Stucco was a typical apartment block: each of its eight units had its own connection to the grid and was free to choose its own retailer, but was severely impeded from choosing to supply itself with on-site renewable energy.

Things changed in late 2015 when the co-op was awarded an Innovation Grant from the City of Sydney with a view to becoming the first apartment block in Australia to be equipped with solar and batteries.

A central part of Stucco’s plan was to share the locally produced renewable energy by converting the building into an “embedded network”, whereby the building has a single grid connection and manages the metering and billing of units internally.

Such a conversion seemed like an ideal solution for solar on apartments, but turned into an ideological battle with the electricity regulator that took months and hundreds of hours of pro bono legal support to resolve.

Layout of Stucco as solar powered embedded network.
Sonia Millway

In this way the Stucco project grew to embody the struggle at the heart of the Australian electricity market: a battle between choice and control, between current regulations that mandate consumers to choose between incumbent retailers, and the public’s aspirations for green self-sufficiency.

A chicken and egg problem

Embedded networks have been around for decades. Yet if the Australian Energy Regulator had its way, they would be banned as soon as possible.

The reason for this is that they inhibit consumers’ choice of retailer: consumers are forced to buy their electricity from the building’s embedded network management company, which may exploit its monopoly power.

Yet it doesn’t have to be this way. At least one company in Germany allows apartment residents to buy power either from their preferred grid retailer or from the building’s solar-powered embedded network. This business model relies on Germany’s smart meter standards that ensure all market participants can access the data they require.

We currently find ourselves in a standoff. The regulator is waiting on companies to offer solar powered embedded networks that include retail competition, while companies are waiting on the regulator to create an accessible playing field that would make such services viable.

The recently released Finkel Report touches on this by recommending a “review of the regulation of individual power systems and microgrids”.

Stucco members celebrating signing the installation contract with Solaray.
Monique Duggan

Stucco’s bespoke solution

In the absence of such a solution, Stucco made a unique agreement with the regulator: the co-op committed to cover fully the costs of installing a grid meter for any unit whose occupant wishes to exit the embedded network in the future.

Such a commitment was feasible because Stucco’s residents, as co-op members, have direct input into the management of the network including controlling prices (that are mandated to be cheaper than any grid offer). But it is difficult to image regular strata committees accepting such liabilities.

Embedded networks are therefore not the best general solution for retrofitting solar on apartments, at least not under current regulations. This is unfortunate because they represent the best utilisation of an apartment block’s solar resource (Stucco’s system provides more than 75% of the building’s electricity) and are therefore increasingly being adopted by developers.

Advice for apartments

The good news for residents of existing apartments is that there are easier routes to installing solar. The even better news is that the cost of solar systems has plummeted (and continues to do so), while retail rates continue to skyrocket, so much so that body corporates are reporting rates of return of 15-20% on their solar investments.

The recommended options for apartments are epitomised by the old adage “keep it simple”. They fall into two categories: a single solar system to power the common area, or multiple smaller systems powering individual units. Which of these is best suited to a particular apartment depends primarily on the building’s size (as a proxy for its energy demand).

Decision tree for solar power on apartments.
Bjorn Sturmberg

For buildings with 1 square metre of sunny roof space per 2m² of floor space (typically blocks up three stories high), it is worth installing a solar system for each unit, as these will typically be well matched to unit’s consumption.

Taller buildings (with less sunshine per apartment) are better off installing a single system for the common area, particularly if this contains power-hungry elements such as elevators or heating and cooling systems.

But here’s the crux: no apartment can install solar without the political support of its strata committee. While this hurdle has historically tripped up many initiatives, increased public awareness has created a groundswell of support. Plus you may need fewer votes than you think.

Myth of the Special Resolution.
Christine Byrne – Green Strata

To improve the chances of overcoming this barrier I have put together a solar-powered apartment pitch deck, available here.

While this article focuses on solar, it is important to remember that the first priority for any building should be to improve energy efficiency, by installing items such as LED lights, modern appliances, and insulation and draft proofing. For advice on these opportunities see the City of Sydney’s Smart Green Apartments website and the Smart Blocks website.

Lastly, adding batteries to an apartment solar system creates extra challenges, for instance fire-prevention planning. But it allows for far greater energy independence and resilience, and a chance to join the future of distributed energy currently being enjoyed by so many of Australia’s non-strata householders.

Stucco Co-operative’s 43.2 kWh battery system.
Bjorn Sturmberg

Bjorn Sturmberg, Associate Lecturer in Physics, Macquarie University

This article was originally published on The Conversation. Read the original article.

Cutting ARENA would devastate clean energy research

Nicky Ison, University of Technology Sydney and Chris Dunstan, University of Technology Sydney

This week’s first sitting of the 45th Parliament of Australia is considering a A$6.5 billion “omnibus savings bill”, including a proposed cut of A$1.3 billion to the Australian Renewable Energy Agency (ARENA). If adopted, it would effectively mean the end of ARENA and would devastate clean energy research in Australia.

From driving innovation and economic growth, to creating jobs, to addressing climate change and ensuring a reliable and affordable energy system for the future, ARENA plays a critical role. Most perversely, by reducing Australia’s role in the booming global clean energy industry, closing ARENA would likely reduce Australia’s capacity to balance its budget in years to come.

What is ARENA?

ARENA, an independent Commonwealth agency, has driven most of Australia’s innovative renewable energy projects in recent years. This includes Australia’s world-leading solar photovaltaics research centre at UNSW, the Carnegie wave energy pilot in Perth, AGL’s virtual power station trial and UTS’s own research into local electricity trading and network opportunity mapping.

ARENA has funded 60 completed projects and is managing a further 200. Many more are in the pipeline. It has also leveraged A$1.30 in private-sector R&D funding for every dollar of government funding – a fact that is often overlooked amid talk of budget savings.

Without ARENA’s grants and leveraged co-funding, very few of these projects would have happened. While its sister organisation, the Clean Energy Finance Corporation, plays an important role in helping to finance established renewable projects and technologies, only ARENA can provide the research grant co-funding to develop these technologies in the first place.

ARENA was formed in 2012 as part of the Gillard government’s Clean Energy Future package. It drew together a range of clean energy programs and funds such as the Solar Flagships, the Australian Solar Institute and some, such as the Low Emissions Technology Demonstration Fund, which the Howard government established. ARENA was given the twin goals of:

1. Improving the competitiveness of renewable energy technologies

2. Increasing the supply of renewable energy in Australia.

ARENA was one of five key elements of the Clean Energy Future package slated for abolition by the Abbott government. While the carbon price and Climate Commission were cut, ARENA, the CEFC and the Climate Change Authority were saved by opposition and crossbench support, albeit with a A$435 million cut to ARENA’s original budget.

Now, three years on, the Turnbull government has chosen to keep the CEFC but its plan to slash ARENA’s budget remains. The Labor opposition has yet to announce its position on the proposed cut. Meanwhile, clean energy researchers across Australia have written an open letter calling on all parties to support the agency.

ARENA’s innovation role

The process of energy technology innovation can be thought of as having a series of phases, which have different funding needs (see below).

The innovation chain for renewable energy technologies.
ISF, based on ARENA’s Commercial Readiness Index, Author provided

The first phase is typically fundamental research and development. Two examples are the world-leading research programs at UNSW Australia and ANU, which have developed the world’s most efficient solar photovoltaic and solar thermal technologies. Both are ARENA-funded; neither could have been effectively funded by loans.

Technologies then need to be piloted in the real world – as in the case of the Carnegie Wave Energy project in Perth. This stage is often still too risky for most commercial lenders, so some public grant funding remains critical.

Next comes the large-scale demonstration phase – bringing technologies down the cost curve by developing viable business models and supply chains, with the aim of making them cost-competitive. Here, a mix of loan and grant funding is needed.

Australia’s large-scale solar industry is an example of a sector in this stage of development. In 2015, ARENA realised that despite having 1.5 million solar roofs and plenty of sunshine, Australia had a dearth of large-scale solar projects (only four operating and four in development). As such, it has committed A$100 million to help build more solar farms.

Finally, there are commercial renewable technologies that are already cost-competitive with other energy sources. Wind energy is the prime example of this, which is precisely why ARENA has not funded wind projects.

Our changing energy system

Innovation is not purely about technology development; it is also about addressing complex challenges such as how to manage the changing nature of our energy system. On a cents per kilowatt-hour basis, wind energy is now cheaper than new-build coal and solar power is cheaper than grid electricity. These two trends will continue, but our energy market is struggling to adapt to the new technology mix.

ARENA has a crucial role to play here. For example, it has funded the Institute of Sustainable Futures (ISF) at UTS to develop a set of Network Opportunity Maps. These show locations in the grid where demand management and decentralised generation (solar, storage etc) can help avoid costly grid upgrades.

ARENA has also funded ISF’s research into local energy trading (also known as peer-to-peer energy or virtual net metering). This is aimed at avoiding the predicted “energy death spiral”, by encouraging consumers and power companies to compromise in making the most of existing infrastructure, reducing consumers’ bills and supporting local power generation.

Meeting our climate targets

Finally, and perhaps most importantly, ARENA is helping to meet Australia’s greenhouse gas emissions target, which calls for a 26-28% cut relative to 2005 levels by 2030.

The electricity sector is Australia’s largest carbon emissions source. ARENA has a vital role in delivering cost-effective emissions reductions. There are two main mechanisms to decarbonise the sector: increasing energy productivity and efficiency, and switching from fossil fuels to renewables. As outlined above, ARENA is a key player in the latter process and is primed to play a leading role in the former.

It would be a tragic error to cut funding to an agency that is making such an important and successful contribution to fulfilling Australia’s obligations under the Paris climate agreement, as well as driving innovation and energy affordability. No other agency combines all of these facets.

More renewable policy instability?

In a 2010 speech on low-carbon energy, Prime Minister Malcolm Turnbull acknowledged the role of government in supporting clean energy innovation, saying:

Government support for innovation and investment in clean stationary energy is important, particularly at the early stages.

The need for this support is not going to go away. If ARENA and its research grant funding is abolished, a similar organisation will doubtless soon need to be re-established. In the meantime, millions of dollars in opportunities would have been wasted and irreplaceable industry and research expertise lost.

After years of policy instability around renewable energy, which has held back the domestic development of one of the world’s fastest-growing industries, do we really want to embrace even more uncertainty?

To paraphrase former Harvard University president Derek Bok, if you think research is expensive, try ignorance.

Nicky Ison, Senior Research Consultant, Institute for Sustainable Futures, University of Technology Sydney and Chris Dunstan, Research Director, Institute for Sustainable Futures, University of Technology Sydney

This article was originally published on The Conversation. Read the original article.

Dear politicians, please don’t endanger world-leading solar research by cutting ARENA

Andrew Blakers, Australian National University

The following is an open letter to parliamentarians from 182 members of Australia’s solar research community.

Dear Members of Australia’s 45th Parliament,

The federal government is proposing to strip the Australian Renewable Energy Agency (ARENA) of most of its funding, and with it its ability to make grants. This is an existential threat to renewable energy research, innovation and education in Australia.

We call upon all political parties to support the retention of ARENA.

The solar photovoltaic (PV) industry now provides one quarter of all new generation capacity installed worldwide each year and is growing at 20-30% per year. Together, PV and wind energy constitute half of all new generation capacity installed worldwide, and all new generation capacity installed in Australia.

A renewable energy revolution is in progress and Australia is currently at the forefront. However, debilitation of ARENA directly threatens our leadership position.

For 30 years there has been an Australian renewable energy funding agency in one form or another. This has led to phenomenal success in generation of technology and provision of education. The worldwide PV industry owes its existence in large measure to Australians who were supported by grants from government renewable energy agencies.

Billions of dollars of benefits have accrued to Australia in the form of dramatically reduced costs of PV systems, rapidly growing renewable energy business activity in Australia, reduced greenhouse gas emissions, royalties, shares and international student fees. For example, the Australian-developed PERC solar cell has annual sales of $10 billion and will soon dominate the worldwide solar industry.

If ARENA is debilitated then hundreds of people would lose their jobs within a year or two. In the longer term, Australia’s leadership in solar energy would vanish. This would be completely at odds with the government’s innovation agenda and its commitment at the Paris climate conference to double clean energy R&D by 2020 under the international Mission Innovation program, and with the ALP’s Climate Change Action Plan launched in 2015 at UNSW Australia, and reinforced by Opposition Leader Bill Shorten at ANU also in 2015.

Support for research and innovation at universities lies at the heart of accelerated growth of the renewable energy industry. It supports later-stage commercialisation directly through technology development. Additionally, university research groups underpin education and training of engineers and scientists.

Echoing the words of another prime minister of a decade ago, Malcolm Turnbull has described budget repair (in which cuts to ARENA are lumped) as a “fundamental moral challenge” because debt should not be passed onto our children and grandchildren.

How ironic if parliament fails to appreciate the many costs to future generations of failing to address climate change now with solutions such as renewable energy.

Yours sincerely,

UNSW Australia: Benjamin Phua, Henner Kampwerth, Mark Keevers, Ziv Hameiri, Catherine Chan, Craig Johnson, Kyung Kim, Li Wang, Mark Silver, Trevor Young, Richard Corkish, Robert Patterson, Binesh Veettil, Christopher Whipp, Dirk Konig, Renate Egan, Bram Hoex, Joyce Ho, Simba Kuestler, Martin Green, David Payne, Robert Taylor, Shira Samocha, Supriya Pillai, Timothy Lee, Udo Romer, Belinda Lam, Natasha Hjerrild, Evatt Hawkes, David Jewkes, Thalia Arnott, Leslie Lay, Muriel Watt, Carlos Vargas, Nathan Thompson, Robert Dumbrell, Daniel Lambert, Nicholas Shaw, Nathan Chang, Anita Ho-Baillie, Ben Wilkensen, Ned Western, Yan Zhu, Lingfeng Wu, Stuart Wenham, Ran Chen, Thilini Ishwara, Steven Limpert, Rolando Vargas, Brett Hallam, Allen Barnett, Santosh Shrestha, Xiaowei Shen, Xiaojing Hao, Saratchandra Tejaswi, Fangzhao Gao, Zhongtian Li, Ivan Perez Wurfl, Qiangshan Ma, Alec Tan, Murad Tayebjee, Ya Zhou, Liam Parnell, Luke Marshall, Jack Colwell, Mable Fong, Alan Yee, Lawrence Soria, Kian Chin, Kamala Vairav, Nancy Sharopeam, Graeme Lennon, Zoe Hungedfold, Bernhard Vogal, Jill Lewis, Ya Zhou, Erny Tsao, Feng Qingge, Yin Li, Thorsten Trupke, Alison Wenham, Ashraf Uddin, Chang Yan, Kaiwen Sun, Yajie Jiang, Yuansim Liao, Marjorie Owens, Shujuan Huang, Sassan Vahdani, Jialiang Huang, Brianna Conrad, Zi Ouyang, Jae sun Yun, Alex Li, Kate Lindsay, Nitin Nampalli

Australian National University: Andrew Blakers, Tom White, Marco Ernst, Fiona Beck, Jie Cui, Andres Cuevas, Erin Crisp, Chris Samondsett, Yimao Wan, Hemant Halmodi, Moshen Goodarzi, Sienpheng Phang, The Duong, Yiliang Wu, Xiao Fu, Kylie Catchpole, Chong Barngkin, Daniel Macdonald, Andrew Thompson, Josephine McKeon, Chang Sun, Kristen Anderson, Anyao Liu, Bin Lu, Matthew Staks, Bruce Condon, Jun Fpeng, Thomas Ratcliff, Hang Sio, Shakir Rahman, Judith Harvey, Klaus Weber, Ingrid Haedrich, Di Yan, Rowena Menkedow, Dale Grant, William Logie, Teck Kong Chong, Hieu Nguyen, Daniel Walte, Sachin Surve, Mark Savvnoeas, Harry Qian, N. Kaines, Nandi Wu

Monash University: Yi-Bing Cheng, Yasmina Dkhissi, Niraj Lal, Jianfeng Lu, Liangcong Jiang, Shannon Bonke, Wei Li, Gaveshana Sepadage, Wemon Mao, Feng Li, Xiangfeng Lin, Udo Bach, Dison Hoogeveen, Iacopo Benesperi, Francsco Paglia, Bin Li, Jiansong Sun, Chanjie Wang, Chunkiu Ng, Maxime Fournier, Boex Tan, Kira Rundel, David Mayeuleg, Jacek Jasieniak, Rebeeca Milhuisen, Masrur Morshed, Kedar Deshmukh, Susaha Frier, Mathias Rothmann

University of Melbourne: Ken Ghiggino, Roger Dargaville, Yann Robiou du Pont, Alex Nauels, Kate Dooley, Malte Meinshausen, Martin Wainstein

Other: Alan Pears (RMIT), Nicola Ison (UTS), Rhett Evans (Solinno), Michelle McCann (PV Lab Australia), Keith McIntosh (PV Lighthouse)

Andrew Blakers, Professor of Engineering, Australian National University

This article was originally published on The Conversation. Read the original article.

Solar households to lose subsidies, but it’s a bright future for the industry

Andrew Blakers, Australian National University

Solar households in Victoria, South Australia and New South Wales will this year cease to be paid for power they export into the electricity grid. In South Australia, some households will lose 16 cents per kilowatt-hour (c/kWh) from September 31. Some Victorian households will lose 25 c/kWh, and all NSW households will stop receiving payments from December 31.

These “feed-in tariffs” were employed to kick-start the Australian solar photovoltaic (PV) industry. They offered high payments for electricity fed back into the grid from roof-mounted PV systems. These varied from state to state and time to time.

For many householders, these special tariffs are ending. Their feed-in tariffs will fall precipitously to 4-8 c/kWh, which is the typical rate available to new PV systems. In some cases households may lose over A$1,000 in income over a year.

But while the windback may hurt some households, it may ultimately be a good sign for the industry.

What can households do?

At present, householders with high feed-in tariffs are encouraged to export as much electricity to the grid as possible. These people will soon have an incentive to use this electricity and thereby displace expensive grid electricity. This will minimise loss of income.

Reverse-cycle air conditioning (for space heating and cooling) uses a lot of power that can be programmed to operate during daylight hours when solar panels are most likely to be generating electricity. The same applies to heating water, either by direct heating or through use of a heat pump. For heating water, solar PV is now competitive with gas, solar thermal and electricity from the grid.

Batteries, both stationary (for house services) and mobile (for electric cars), will also help control electricity use in the future.

A boost for the industry?

The ending of generous feed-in tariffs is likely to modestly encourage the solar PV industry. This is because many existing systems have a rating of only 1.5 kilowatts (kW), which could not have been increased without loss of the generous feed-in tariff.

Many householders will now choose to increase the size of their PV system to 5-10kW – in effect a new system given the disparity in average PV sizing between then and now.

A new large-scale PV market is also opening on commercial rooftops. Many businesses have daytime electrical needs that are better matched to solar availability than are domestic dwellings.

This allows businesses to consume the large amounts of the power their panels produce and hence minimise high commercial electricity tariffs. The constraining factors in this market are often not technical or economic, and include the fact that many businesses rent from landlords and tend to have short terms for investment. Business models are being developed to circumvent these constraints.

The rooftop PV market also now has large potential in competing with retail electricity prices. The total cost of a domestic 10kW PV system is about A$15,000. Over a 25-year lifetime this would yield an energy cost of 7 c/kWh.

This is about one-quarter of the typical Australian retail electricity tariff, about half of the off-peak electricity tariff, and similar to the typical retail gas tariff. Rooftop PV delivers energy services to the home more cheaply than anything else and has the capacity to drive natural gas out of domestic and commercial markets.

According to the Australian Bureau of Statistics, there are 9 million dwellings in Australia, and the floor area of new residential dwellings averaged 200 square metres over the past 20 years. Some of these dwellings are in multi-storey blocks, others have shaded roofs and, of course, south-facing roofs are less suitable than other orientations for PV.

However, if half the dwellings had one-third of their roofs covered in 20% efficient PV panels then 60 gigawatts (GW) could be accommodated. For perspective, this would cover 40% of Australian electricity demand. Commercial rooftops are a large additional market.

Solar getting big

Virtually all PV systems in Australia are roof-mounted. However, this is about to change because ground-mounted PV systems are becoming competitive with wind energy. We can see the falling cost of solar in the Queensland Solar 120 scheme, the Australian Capital Territory wind and PV reverse auctions and the Australian Renewable Energy Agency Large Scale Solar program , which all point to the declining cost of PV and wind.

Together, wind and PV constitute virtually all new generation capacity in Australia and half of the new generation capacity installed worldwide each year.

The total cost of a 10-50 megawatt PV system (1,000 times bigger than a 10kW system) is in the range A$2,100/kW (AC). A 25-year lifetime yields an energy cost of 8 c/kWh. This is only a little above the cost of wind energy and is fully competitive with new coal or gas generators.

Hundreds of 10-50MW PV systems can be distributed throughout sunny inland Australia close to towns and high-capacity powerlines. Australia’s 2020 renewable energy target is likely to be met with a large PV component, in addition to wind.

Wide distribution of PV and wind from north Queensland to Tasmania minimises the effect of local weather and takes full advantage of the complementary nature of the two leading renewable energy technologies.

The declining cost of PV and wind, coupled with the ready availability of pumped hydro storage, allows a high renewable electricity fraction (70-100%) to be achieved at modest cost by 2030.

Andrew Blakers, Professor of Engineering, Australian National University

This article was originally published on The Conversation. Read the original article.

Wind and solar PV have won the race – it’s too late for other clean energy technologies

Andrew Blakers, Australian National University

Across the world, solar photovoltaics (PV) and wind are the dominant clean energy technologies. This dominance is likely to become overwhelming over the next few years, preventing other clean energy technologies (including carbon capture and storage, nuclear and other renewables) from growing much.

As the graph below shows, PV and wind constitute half of new generation capacity installed worldwide, with fossil, nuclear, hydro and all other renewable energy sources making up the other half. In Australia this dominance is even clearer, with PV and wind constituting virtually all new generation capacity.

Moreover, this trend is set to continue. Wind and PV installation rates grew by 19% in 2015 worldwide, while rates for other technologies were static or declined.

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PV and wind dominate because they have already achieved commercial scale, are cheap (and set to get cheaper), and are not constrained by fuel availability, environmental considerations, construction materials, water supply, or security issues.

In fact, PV and wind now have such a large head start that no other low-emission generation technology has a reasonable prospect of catching them. Conventional hydro power cannot keep pace because each country will sooner or later run out of rivers to dam, and biomass availability is severely limited.

Heroic growth rates would be required for nuclear, carbon capture and storage, concentrating solar thermal, ocean energy and geothermal to span the 20- to 200-fold difference in annual installation scale to catch wind and PV – which are themselves growing rapidly.

Both wind and PV access massive economies of scale. Their ability to saturate national electricity markets around the world severely constrains other low-emission technologies. Some of the other technologies may become significant in some regions, but these will essentially be niche markets, such as geothermal in Iceland, or hydro power in Tasmania.

Around 80% of the energy sector could be electrified in the next two decades, including electrification of land transport (vehicles and public transport) and electric heat pumps for heat production. This will further increase opportunities for PV and wind, and allows for the elimination of two-thirds of greenhouse gas emissions (based upon sectoral breakdown of national emissions data).

Storage and integration

What about the oft-cited problems with the variable nature of photovoltaics and wind energy? Fortunately, there is range of solutions that can help them achieve high levels of grid penetration.

While individual PV and wind generators can have very variable outputs, the combined output of thousands of generators is in fact quite predictable when coupled with good weather forecasting and smoothed out over a wide area.

What’s more, PV and wind often produce power under different weather conditions – storms favour wind, whereas calm conditions are often sunny. Rapid improvements in high-voltage DC transmission allows large amounts of power to be transmitted cheaply and efficiently over thousands of kilometres, meaning that the impact of local weather is less important.

Another option is “load management”, in which power demands for things like domestic and commercial water heating, and household and electric car battery charging, are moved from night time to day to coincide with availability of sun and wind. Existing hydro and gas or biogas generators, operated for just a small fraction of the year, can also help.

Finally, mass power storage is already available in the form of pumped hydro energy storage (PHES), in which surplus energy is used to pump water uphill to a storage reservoir, which is then released through a turbine to recover around 80% of the stored energy later on. This technology constitutes 99% of electricity storage worldwide and is overwhelmingly dominant in terms of new storage capacity installed each year (3.4 Gigawatts in 2015).

Australia already has several PHES facilities, such as Wivenhoe near Brisbane and Tumut 3 in the Snowy Mountains. All of these are at least 30 years old, but more can be built to accommodate the storage needs of new wind and PV capacity. Modelling underway at the Australian National University shows that reservoirs containing enough water for only 3-8 hours of grid operation is sufficient to stabilise a grid with about 90% PV and wind – mostly to shift daytime solar power for use at night.

This would require only a few hundred hectares of reservoirs for the Australian grid, and could be accomplished by building a series of “off-river” pumped hydro storages. Unlike conventional “on-river” hydro power, off-river PHES requires pairs of hectare-scale reservoirs, rather like oversized farm dams, located in steep, hilly, farm country, separated by an altitude difference of 200-1000 metres, and joined by a pipe containing a pump and turbine.

One example is the proposed Kidston project in an old gold mine in north Queensland. In these systems water goes around a closed loop, they consume very little water (evaporation minus rainfall), and have a much smaller environmental impact than river-based systems.

How renewables can dominate Australian energy

In Australia, if wind and PV continue at the installation rate required to reach the 2020 renewable energy target (about 1 GW per year each), we would hit 50% renewable electricity by 2030. This rises to 80% if the installation rates double to 2 GW per year each under a more ambitious renewable energy target – the barriers to which are probably more political than technological.

PV and wind will be overwhelmingly dominant in the renewable energy transition because there isn’t time for another low-emission technology to catch them before they saturate the market.

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Wind, PV, PHES, HVDC and heat pumps are proven renewable energy solutions in large-scale deployment (100-1,000 GW installed worldwide for each). These technologies can drive rapid and deep cuts to the energy sector’s greenhouse emissions without any heroic assumptions.

Apart from a modest contribution from existing hydroelectricity, other low-emission technologies are unlikely to make significant contributions in the foreseeable future.

Andrew Blakers, Professor of Engineering, Australian National University

This article was originally published on The Conversation. Read the original article.