The link below is to an article reporting on the approval of Australia’s largest wind farm in Queensland.
Moving to a future powered mainly by renewable energy will be crucial if we are to stay within the global warming limits set out by the Paris Agreement. But building all of this new renewable energy will initially require fossil fuels to help power all of the necessary mining, construction and decommissioning. This raises the question as to whether the energy transition itself will be pointless.
But new research by a group at UNSW (Bahareh Sara Howard, Nick Hamilton, Tommy Wiedmann and myself) shows that it is theoretically possible for Australia to move to a renewable energy future without blowing its share of the carbon budget.
Actually doing it will require two things: prompt, decisive action, and a reliance on “renewable energy breeding” – the process by which mining the raw materials and manufacturing technologies such as solar cells and wind turbines are themselves powered by renewables rather than fossil fuels.
Already under way
This renewable energy breeding is already under way in some places. Tesla’s solar panel factory in Nevada, known as Gigafactory 1, will itself run on solar power. In South Australia, Liberty OneSteel, the new owner of the Whyalla steelworks, is planning solar power, pumped hydro, batteries and demand management to reduce energy costs and greenhouse emissions. In Western Australia, Sandfire Resources’ DeGrussa gold and copper mine and Galaxy Resources’ lithium mine are both going solar.
These are encouraging developments. But will they be enough? The world has only a limited emissions budget left to keep global warming below the Paris Agreement’s 2℃ limit, and an even smaller budget for the agreement’s more ambitious 1.5℃ goal.
As Australia is responsible for about 1% of global emissions and its electricity industry is responsible for about one-third of that, we have assumed that the country’s carbon budget for electricity generation is about one-third of 1% of the global carbon budget. Overall, then, this gives us a total carbon budget for Australia’s electricity sector of 3.3 gigatonnes of carbon dioxide equivalent (post-2011) for the 2℃ target, and 1.3 gigatonnes for the 1.5℃ target. For comparison, Australia’s annual carbon dioxide equivalent emissions are over half a gigatonne (actually 0.55 gigatonnes), so we are only three years away from overshooting the 1.5℃ target.
Even these budgets are generous, because Australia is one of the biggest per capita carbon dioxide emitters in the world and has enormous renewable energy resources.
What’s more, electricity is the easiest part of the energy sector to move to renewable energy – heating and transport are more difficult prospects. This means that if we are to move to an entirely renewable energy future, most heating and transport will need to be electrified. Therefore, electricity should have a greater emissions reduction target than other sectors.
Making the transition
Our study, which builds on earlier research, looked at 22 possible scenarios for transitioning Australia’s electricity sector to predominantly renewable energy. Some were developed by us, and some by other research groups.
Crucially, our study factored in the “life-cycle” emissions of these energy generation technologies – that is, the total greenhouse emissions including those released during the manufacture of the technologies themselves. And we looked explicitly at renewable energy breeding as part of that analysis.
Our scenarios also assume that overall electricity demand will either stabilise or decline, despite the move towards electrifying transport and heating. This is because Australia is well placed to make huge improvements in energy efficiency.
Rapid action needed
The principal findings of our research include the good news that the life-cycle greenhouse emissions from manufacturing renewable energy technologies such as solar panels and wind turbines are tiny, compared with the emissions saved by using them as substitutes for fossil fuels.
With the help of renewable energy breeding, the overall life-cycle emissions savings can be substantial – more than 90%, in some of the scenarios we examined. Therefore, manufacturers of renewable energy systems should use renewable energy to power their production lines.
The bad news is that, in every scenario we investigated, Australia nevertheless fails to achieve its share of the ambitious emissions reductions needed to limit global warming to 1.5℃ with 66% probability. Furthermore, 9 of our 22 scenarios also fail the more lenient 2℃ target.
The main reason for this is the legacy of CO₂ emissions from fossil fuel use before the renewable energy transition. In most of our scenarios, the benefits of renewable energy breeding to the cumulative emissions become significant only beyond 2040.
The scenario (S8a, labelled V in the graph above) that comes closest to achieving the 1.5℃ target involves a 98% transition to renewable electricity and a 35% reduction in electricity demand by 2030 – a very rapid transition indeed!
The scenarios that deliver on the 2℃ target have rapid and high penetrations of renewable energy into the market, and high contributions from energy efficiency.
While it may already be too late for Australia to make a fair contribution to keeping global warming at 1.5℃, our results show that we can stay within our share of the carbon budget for 2℃ – provided we have the political will to move fast.
What’s more, if we implement policies that incentivise renewable energy breeding, there is no reason to suppose that moving to 100% renewable energy would necessarily entail a large increase in emissions to produce the necessary technologies.
But the overriding message is that time is of the essence, if we want to come anywhere close to limiting dangerous climate change. Our various scenarios suggest that even if we implement a rapid, effective response, we are likely to have to take CO₂ back out of the atmosphere in the future, to compensate for the likely overshoot on our share of the global carbon budget.
Solar photovoltaic and wind power are rapidly getting cheaper and more abundant – so much so that they are on track to entirely supplant fossil fuels worldwide within two decades, with the time frame depending mostly on politics. The protestation from some politicians that we need to build new coal stations sounds rather quaint.
The reality is that the rising tide of solar photovoltaics (PV) and wind energy offers our only realistic chance of avoiding dangerous climate change.
No other greenhouse solution comes close, and it is very hard to envision any timely response to climate change that does not involve PV and wind doing most of the heavy lifting.
About 80% of Australia’s greenhouse gas emissions are due to the use of coal, oil and gas, which is typical for industrialised countries. The land sector accounts for most of the rest.
Sadly, attempts to capture and store the carbon dioxide emissions from fossil fuels have come to naught due to technical difficulties and high cost. Thus, to curtail global warming we need to replace fossil fuel use entirely, with energy sources that meet these criteria:
- very large and preferably ubiquitous resource base
- low or zero greenhouse gas emissions and other environmental impacts
- abundant or unlimited raw materials
- minimal security concerns in respect of warfare, terrorism and accidents
- low cost
- already available in mass production.
Solar PV meets all of these criteria, while wind energy also meets many of them, although wind is not as globally ubiquitous as sunshine. We will have sunshine and wind for billions of years to come. It is very hard to imagine humanity going to war over sunlight.
Most of the world’s population lives at low latitudes (less than 35°), where sunlight is abundant and varies little between seasons. Wind energy is also widely available, particularly at higher latitudes.
PV and wind have minimal environmental impacts and water requirements. The raw materials for PV – silicon, oxygen, hydrogen, carbon, aluminium, glass, steel and small amounts of other materials – are effectively in unlimited supply.
Wind energy is an important complement to PV because it often produces at different times and places, allowing a smoother combined energy output. In terms of worldwide annual electricity production wind is still ahead of PV but is growing more slowly. The wind energy resource is much smaller than the solar resource, and so PV will likely dominate in the end.
Complete replacement of all fossil fuels requires solar and wind collectors covering much less than 1% of the world’s land surface area. A large proportion of the collectors are installed on rooftops and in remote and arid regions, thus minimising competition with food production and ecosystems.
The more widely PV and wind generation are distributed across the world, the less the risk of wide-scale disruption from natural disasters, war and terrorism.
Other clean energy technologies can realistically play only a minor supporting role. The solar thermal industry is hundreds of times smaller than the fast-growing PV industry (because of higher costs). Hydro power, geothermal, wave and tidal energy are only significant prospects in particular regions.
Biomass energy is inefficient and its requirement for soil, water and fertiliser put it in conflict with food production and ecosystems. Nuclear is too expensive, and its construction rates are too slow to catch PV and wind.
A renewable grid
PV and wind are often described as “intermittent” energy sources. But stabilising the grid is relatively straightforward, with the help of storage and high-voltage interconnectors to smooth out local weather effects.
The cost of PV and wind power has been declining rapidly for many decades and is now in the range A$55-70 per megawatt-hour in Australia. This is cheaper than electricity from new-build coal and gas units. There are many reports of PV electricity being produced from very large-scale plants for A$30-50 per MWh.
Solar PV and wind have been growing exponentially for decades and have now reached economic lift-off. In 2018, PV and wind will comprise 60% of net new electricity generation capacity worldwide. Coal, gas, nuclear, hydro and other renewable capacity comprise the rest. Globally, US$161 billion will be invested in solar generation alone this year, compared with US$103 billion in new coal and gas combined.
PV and wind are growing at such a rate that the overall installed generation capacity of PV and wind has reached half that of coal, and will pass coal in the mid-2020s, judging by their respective trends.
In Australia, PV and wind comprise most new generation capacity. About 4.5 gigawatts of PV and wind is expected to be installed in 2018 compared with peak demand of 35GW in the National Electricity Market. At this rate, Australia would reach 70% renewable electricity by 2030.
Together, PV and wind currently produce about 7% of the world’s electricity. Worldwide over the past five years, PV capacity has grown by 28% per year, and wind by 13% per year. Remarkably, because of the slow or nonexistent growth rates of coal and gas, current trends put the world on track to reach 100% renewable electricity by 2032.
Deep cuts (80% reduction) in greenhouse gas emissions require that fossil fuels are pushed out of all sectors of the economy. The path to achieve this is by electrification of all energy services.
Straightforward and cost-effective initial steps are: to hit 100% renewable electricity; to convert most land transport to electric vehicles; and to use renewable electricity to push gas out of low-temperature water and space heating. These trends are already well established, and the outlook for the oil and gas industries is correspondingly poor.
The best available prices for PV already match the current wholesale price of gas in Australia (A$9 per gigajoule, equivalent to A$32 per MWh for heat).
High-temperature heat, industrial processes, aviation and shipping fuel and fugitive emissions can be displaced by renewable electricity and electrically produced synthetic fuels, plastics and other hydrocarbons. There may be a modest additional cost depending on the future price trajectory of PV and wind.
Electrifying the whole energy sector of our economy of course means that electricity production needs to increase massively – roughly tripling over the next 20 years. Continued rapid growth of PV (and wind) will minimise dangerous climate change with minimal economic disruption. Many policy instruments are available to hasten their deployment. Governments should get behind PV and wind as the last best chance to deliver the necessary solution to global warming.
As the world embraces inherently variable renewable energy sources to tackle climate change, we will need a truly gargantuan amount of electrical energy storage.
With large electricity grids, microgrids, industrial installations and electric vehicles all running on renewables, we are likely to need a storage capacity of over 10% of annual electricity consumption – that is, more than 2,000 terawatt-hours of storage capacity worldwide as of 2014.
To put that in context, Australia’s planned Snowy 2.0 pumped hydro storage scheme would have a capacity of just 350 gigawatt-hours, or roughly 0.2% of Australia’s current electricity consumption.
Where will the batteries come from to meet this huge storage demand? Most likely from a range of different technologies, some of which are only at the research and development stage at present.
Our new research suggests that “proton batteries” – rechargeable batteries that store protons from water in a porous carbon material – could make a valuable contribution.
Not only is our new battery environmentally friendly, but it is also technically capable with further development of storing more energy for a given mass and size than currently available lithium-ion batteries – the technology used in South Australia’s giant new battery.
Potential applications for the proton battery include household storage of electricity from solar panels, as is currently done by the Tesla Powerwall.
With some modifications and scaling up, proton battery technology may also be used for medium-scale storage on electricity grids, and to power electric vehicles.
How it works
Our latest proton battery, details of which are published in the International Journal of Hydrogen Energy, is basically a hybrid between a conventional battery and a hydrogen fuel cell.
During charging, the water molecules in the battery are split, releasing protons (positively charged nuclei of hydrogen atoms). These protons then bond with the carbon in the electrode, with the help of electrons from the power supply.
In electricity supply mode, this process is reversed: the protons are released from the storage and travel back through the reversible fuel cell to generate power by reacting with oxygen from air and electrons from the external circuit, forming water once again.
Essentially, a proton battery is thus a reversible hydrogen fuel cell that stores hydrogen bonded to the carbon in its solid electrode, rather than as compressed hydrogen gas in a separate cylinder, as in a conventional hydrogen fuel cell system.
Unlike fossil fuels, the carbon used for storing hydrogen does not burn or cause emissions in the process. The carbon electrode, in effect, serves as a “rechargeable hydrocarbon” for storing energy.
What’s more, the battery can be charged and discharged at normal temperature and pressure, without any need for compressing and storing hydrogen gas. This makes it safer than other forms of hydrogen fuel.
Powering batteries with protons from water splitting also has the potential to be more economical than using lithium ions, which are made from globally scarce and geographically restricted resources. The carbon-based material in the storage electrode can be made from abundant and cheap primary resources – even forms of coal or biomass.
Our latest advance is a crucial step towards cheap, sustainable proton batteries that can help meet our future energy needs without further damaging our already fragile environment.
The time scale to take this small-scale experimental device to commercialisation is likely to be in the order of five to ten years, depending on the level of research, development and demonstration effort expended.
Our research will now focus on further improving performance and energy density through use of atomically thin layered carbon-based materials such as graphene.
The target of a proton battery that is truly competitive with lithium-ion batteries is firmly in our sights.
Nothing uses more resources or produces more waste than the buildings we live and work in. Our built environment is responsible for half of all global energy use and half of all greenhouse gas emissions. Buildings consume one-sixth of all freshwater, one-quarter of world wood harvests and four-tenths of all other raw materials. The construction and later demolition of buildings produces 40% of all waste.
The sustainability of our buildings is coming under scrutiny, and “green” rating tools are the key method for measuring this. Deakin University’s School of Architecture and Built Environment recently reviewed these certification schemes. Focus group discussions were held in Sydney and Melbourne with representatives in the field of sustainability – including government, green consultancies and rating tool providers.
Two main concerns emerged from our review:
Sustainability ratings tools are not audited. Most ratings tools are predictive, while those few that take measurements use paid third parties. Government plays no active part.
The sustainability parameters measured only loosely intersect with the building occupants’ sustainability concerns. Considerations such as access to transport and amenities are not included.
That’s the backdrop to the sustainability targets now being adopted across Australia. Australia has the highest rate of population growth of any developed country. The population now is 24.8 million. It is expected to reach between 30.9 and 42.5 million people by 2056.
More buildings will be needed for these people to live and work in. And we will have to find ways to ensure these buildings are more sustainable if the targets now being adopted are to be achieved.
So how do green ratings work?
Each green rating tool works by identifying a range of sustainability parameters – such as water and energy use, waste production, etc. The list of things to be measured runs into the dozens. Tools differ on the parameters measured, method of measurement, weightings given and the thresholds that determine a given sustainability rating.
There are over 600 such rating tools worldwide. Each competes in the marketplace by looking to reconcile the credibility of its ratings with the disinclination of developers to submit to an assessment that will rate them poorly. Rating tools found in Australia include Green Star, NABERS, NatHERS, Circles of Sustainability, EnviroDevelopment, Living Community Challenge and One Planet Communities.
So, it is easy enough to find landmark developments labelled with green accreditations. It is harder to quantify what these actually mean.
Ratings must be independently audited
Government practice, historically, has been to assure building quality through permits. Planning permits ensure a development conforms with city schemes. Building permits assess structural load-bearing capacity, health and fire safety.
All this is done off the plan. Site inspections take place to verify that the building is built to plan. But once a certificate of occupancy is issued, the government steps aside.
The sustainability agenda promoted by government has been grafted onto this regime. Energy efficiency was introduced into the residential building code in 2005, and then into the commercial building code in 2006. At first, this was limited to new buildings, but then broadened to include refurbishment of existing structures.
Again, sustainability credentials are assessed off the plan and certification issued once the building is up and running. Thereafter, government walks away.
We know of only one longitudinal energy performance study carried out on domestic residences in Australia. It is an as-yet-unpublished project conducted by a retiree from the CSIRO, working with Indigenous communities in Far North Queensland.
The findings corroborate a recent study by Gertrud Hatvani-Kovacs and colleagues from the University of South Australia. This study found that so-called “energy-inefficient” houses, following traditional design, managed under certain conditions to outperform 6- and 8-star buildings.
Sustainability tools must measure what matters
Energy usage is but the tip of the iceberg. Genuine sustainability is about delivering our children into a future in which they have all that we have today.
Home owners, on average, turn their property around every eight years. They are less concerned with energy efficiency than with real estate prices. And these prices depend on the appeal of the property, which involves access to transport, schools, parks and amenities, and freedom from crime.
Commercial property owners, too, are concerned about infrastructure, and they care about creating work environments that retain valued employees.
These are all core sustainability issues, yet do not come up in the rating systems we use.
If government is serious about creating sustainable cities, it needs to let go of its limited, narrow criteria and embrace these larger concerns of “liveability”. It must embody these broader criteria in the rating systems it uses to endorse developments. And it needs an auditing and enforcement regime in place to make it happen.
Ralph Horne, RMIT University; Emma Baker, University of Adelaide; Francisco Azpitarte, University of Melbourne; Gordon Walker, Lancaster University; Nicola Willand, RMIT University, and Trivess Moore, RMIT University
Energy efficiency in Australian homes is an increasingly hot topic. Spiralling power bills and the growing problem of energy poverty are set against a backdrop of falling housing affordability, contested carbon commitments and energy security concerns.
Most people agree we need modern, comfortable, eco-efficient homes. This article is not about the relatively few, new, demonstration “eco-homes” dotted around Australia. It is about the rest of our housing.
These mainly ageing homes might have had energy efficiency improvements done over the years, but invariably are in need of upgrading to meet modern standards of efficiency and comfort.
Since 2006, all new-build housing must meet higher energy efficiency standards. But we add only around 1% to the new housing stock each year.
Policies to improve energy efficiency in the other 99% are more fragmented. The focus is almost entirely on market-based incentives to “retrofit”. By this we mean material upgrades to improve housing energy and carbon performance.
The transition has begun
Nevertheless, a major retrofit transition is under way. In the last decade, around one in five Australian households has installed solar panels. More than three million upgrades have been carried out through the Victorian Energy Efficiency Target (now Victorian Energy Upgrades) initiative.
These impressive numbers describe a nationally important intervention. But does this mean we will soon all get to live in eco-homes, rather than just a lucky few?
Current retrofitting activity has occurred unevenly and may contribute to longer-term inequalities.
For example, rebates for deeper retrofits often are more accessible to the better-off home owners. They have matching cash and also rights to make major upgrades (as opposed to renters). This entrenches the existing reality that low-income renters tend to live in less energy-efficient homes.
Similarly, in the UK, retrofit incentives haven’t always successfully targeted those most in need. The distribution of costs has contributed to pushing up energy prices for those already in energy poverty. In Australia, up to 20% of households were already in energy poverty before recent price rises.
Thus, if poorly targeted and funded, energy efficiency initiatives might make existing dynamics worse and add to the cumulative vulnerabilities of housing affordability stress.
Keeping track of how homes rate
We cannot effectively monitor this. This is because Australia has no robust, longitudinal national database of property condition. There is no established, widespread practice of property owners obtaining property condition reports that set out the energy-efficiency performance and the most viable improvements that could be made.
This means we do not have a systematic way of knowing what we should do next to our homes, even if we are lucky enough to own them and have some cash available, as well as the time and motivation to retrofit.
To the rescue, at least in Victoria, is the new Victorian Residential Efficiency Scorecard. This is an advance on previous attempts (as in the ACT and Queensland) to develop comparable assessments of the energy efficiency and comfort levels of your home. Although voluntary, the scorecard will provide owners with a report on their home and a list of measures they can consider to transform it “eco-homewards”.
So, is the scorecard the answer to our problems? Will it bring forward the date when we can all live in comfy eco-homes? It will certainly help.
The European Union has had a mandatory system since the Energy Performance in Buildings Directive. The evidence suggests this has raised awareness of energy efficiency by literally putting labels of buildings in your face when you are deciding where to buy. It’s much like Australians have become used to energy efficiency labels on fridges and other appliances. However, evidence of this awareness actually leading to upgrade activity is more mixed and, in some cases, disappointing.
In short, we need the scorecard and should welcome it. However, we also need a set of other measures if we are to make the transformations to match our national policy objectives and our desires for a comfy eco-home.
What else needs to be done?
The research agenda is also shifting to explore the social and equity dimensions of the retrofit transition.
In areas where installation work on energy-efficiency/low-carbon retrofits is increasing, how is this working in households? Who makes decisions? How do they decide and with what resources? What or who do they call upon? And, more broadly, what are the positive or problematic consequences for equity and, therefore, for policy?
Emerging retrofit technologies and behaviours have broader social and economic contexts. This means we need to understand the wider meanings and practices of homemaking, the uneven social and income structures of households, and the home improvement service industry.
While the retrofit transition is arguably under way, its consequences and dynamics are still largely unknown. We need to refocus away from simply counting solar systems towards understanding retrofitting better. This depends on understanding both the households that are retrofitting their homes and the industries and organisations that supply them.
To get energy policies right and overcome energy poverty, we need to bring together studies and initiatives in material consumption, sustainability and social justice.
Ralph Horne, Deputy Pro Vice Chancellor, Research & Innovation; Director of UNGC Cities Programme; Professor, RMIT University; Emma Baker, Associate Professor, School of Architecture and Built Environment, University of Adelaide; Francisco Azpitarte, Ronald Henderson Research Fellow Melbourne Institute of Applied Economic and Social Research & Brotherhood of St Laurence, University of Melbourne; Gordon Walker, Professor at the DEMAND Centre and Lancaster Environment Centre, Lancaster University; Nicola Willand, Research Consultant, Sustainable Building Innovation Laboratory, RMIT University, and Trivess Moore, Research Fellow, RMIT University