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ReNew Editor, Robyn Deed

ReNew 137 editorial: Solar and storage, at home and abroad

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IT’S a challenging time for consumers sorting out what’s what in the rapidly evolving world of energy storage. New products are coming onto the market every other day, or at least being announced, so what’s true yesterday may not hold true tomorrow.


That being said, we at ReNew are never ones to shy away from a challenge. We aim to get behind the hype and help with the nitty gritty details you need to make a decision. So this issue we take a look at what you need to consider when going off-grid or installing a hybrid system with grid-connected storage. We look at the battery technologies on the market and the inverters that drive the way such systems are installed. Along with new and cheaper battery systems, inverters are evolving at such a rate that the traditional divisions between off-grid and grid-interactive are breaking down—with new hybrid inverters and control software providing many ways to optimise usage and storage of your solar energy.

Three out of four of our case studies combine off-grid or hybrid systems with an electric vehicle, an encouraging trend, which we also put under the spotlight in an EV market update. Our householders’ stories also show that one of the biggest wins from installing solar+storage is that it really focuses attention on how much energy you use, and when.

One of the owners in a mini-grid trial in Mooroolbark is a case in point: being given monitoring tools and energy efficiency information has already changed their behaviour, only a month or so after their system was installed. And they get to share their energy (and knowledge) with their neighbours. Small-scale energy sharing is a bit of a focus this issue too—just what are the benefits of the mini-grids and virtual power plants that are all over the news just now?

Given all the buzz about energy storage, it’s not surprising that course providers are tipping that’s where skills will be needed. Our renewable energy courses guide is a must-read if you’re considering a career in this area.

On another note, our reader challenges always bring home the engaged community that makes ReNew what it is. In our recent photo competition, we were overwhelmed by the responses, both in number and quality, illustrating the many ways that ReNew readers interact with that somewhat overused word ‘sustainability’: from carefully thought-through transport options to renewable energy systems to communities sharing skills, food and more. Unfortunately, we couldn’t include all the entries in the magazine, but we hope to bring you more in the future.

Two decades on, this issue also brings you the 79th Pears Report, an integral part of ReNew—people often note it’s the first thing they read each issue. For the many fans, we’ve now collected 75 columns into an eBook, with support from RMIT’s sustainability fund, and launching in October. Enjoy!

Robyn Deed
ReNew Editor


ATA CEO’s Report

WHEN I started at the ATA many years ago, one of the first people I was told to meet was Alan Pears. As many of you know, Alan has been a leading light in energy efficiency and climate change policy over many years.

Currently a Senior Industry Fellow at RMIT University, Alan has been an important contributor to the development of Australia’s sustainable energy and energy efficiency policies, programs and projects since the late 1970s, and a passionate climate response advocate since the late 80s.

His expertise is regularly called upon by governments and agencies, businesses, community organisations and the media; variously as consultant, mentor, award judge, advisor, reviewer and commentator. His achievements in this arena have been acknowledged with numerous industry awards and, in 2009, with his appointment as a Member of the Order of Australia.

We are very excited at the ATA to be launching The Pears Report eCollection: Reflections on Two Decades of Energy and Climate Policy in Australia—75 Articles from ReNew Magazine, 1997–2016 at the All Energy Expo in October. The collection brings together the detailed, accurate and thoughtful insights from The Pears Report columns in ReNew, along with a new and substantial series of articles by Alan discussing the major topics and themes.

Alan has been a great mentor and advisor to many of us, generous with providing his time and expertise especially to not-for-profit organisations like the ATA. We are proud to be able to acknowledge Alan’s invaluable contribution to energy market reform and a better Australia.

Donna Luckman

You can purchase ReNew 137 from the ATA webshop.


Just add batteries

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There’s more to consider than just the brand or size when adding storage to a solar system. Damien Moyse and Nick Carrazzo highlight some of the issues to consider in a field with ever-evolving technology.

There are multiple ways that batteries can be added to an existing or new solar PV system. These different configurations will influence the system’s capabilities so it’s important to carefully consider the approach you take. This article covers the most common approaches currently available in Australia, but note that technology and options are developing rapidly so we will be updating this advice regularly.


The majority of solar PV systems currently installed in Australia are unlikely to be ‘battery-ready’—an existing solar customer cannot simply purchase a lead-acid, lithium ion, flow or sodium battery and have it retrofitted to their existing system.

The solar panels can be retained, of course, but an additional or replacement inverter and charging components will likely be needed to charge and use the batteries.

One approach (DC coupling) involves replacing the existing grid-interactive inverter with a new hybrid inverter; such inverters can both control charging of the battery and conversion of electricity from DC to the AC required for household use. As a cheaper alternative, in a fairly recent development, the replacement of the grid-interactive inverter can be avoided through fitting a DC to DC converter between the solar array and the battery bank—thereby negating the need to replace the existing grid-interactive inverter.

A second approach (AC coupling) requires installation of a second battery-dedicated hybrid inverter (with integral charger controller), with the existing grid-interactive inverter retained.

As such, almost all the new battery products currently on the Australian market are either sold with a new inverter (some as part of an integrated ‘all-in-one’ storage unit and some with the inverter separate from the battery) or require an inverter to be purchased separately.

Thus, most existing solar customers will need to replace their existing grid-interactive solar inverter, add a second inverter or add a DC to DC converter to their system. Which approach is taken depends on whether the system uses AC or DC coupling and the capabilities required of the system. Coupling refers to where within the system the batteries are connected.

Read the full article in ReNew 137.


Tassie off-grid home

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Given their distance from the nearest power pole, it made sense financially as well as philosophically for this Sydney couple to go off-grid in their new home in Tasmania. Peter Tuft describes how they went about it.

As we approached retirement my wife Robyn and I knew we did not want to spend the rest of our lives in Sydney. Sydney’s natural environment is glorious but it is also much too busy, too hot and humid in summer, and our house was too cold and hard to heat in winter. We had loved Tasmania since bushwalking there extensively in the 1970s and it has a lovely cool climate, so it was an obvious choice.


We narrowed the selection to somewhere within one hour‘s drive of Hobart, then on a reconnaissance trip narrowed it further to the Channel region to the south. It has lush forests and scattered pasture with the sheltered d’Entrecasteaux Channel on one side and tall hills behind—just beautiful. And we were extraordinarily lucky to quickly find an 80 hectare lot which had all those elements plus extensive views over the Channel and Bruny Island to the Tasman Peninsula. It was a fraction of the cost of a Sydney suburban lot.

The decision to buy was in 2008 but building did not start until 2014 so we had plenty of time to think about what and how to build. We have always been interested in sustainability, and renewable energy in particular, even before they became so obviously necessary: my engineering undergraduate thesis in 1975 was on a solar heater and Robyn worked for many years on wastewater treatment and stream water quality. There was never any doubt that we would make maximum use of renewable energy and alternative waste disposal methods.

From the beginning we knew the house would be of passive solar thermal design. The house sits high on a hill (for the views!) and faces north-east. The main living room is entirely glass-fronted, about 11m long and up to 4m high with wide eaves. That allows huge solar input to the floor of polished concrete. A slight downside is that there is potential for it to be too warm in summer, but we’ve managed that with shade blinds and ventilation and so far it has not been a problem. All walls, floor and roof are well insulated, even the garage door, and all windows are double-glazed. Supplementary heating is via a wood heater set in a massive stone fireplace chosen partly for thermal mass and partly because it just looks awesome. Warm air from above the wood heater convects via ducts to the bathroom immediately behind the chimney, making it very cosy indeed.

Read the full article in ReNew 137.


Australia’s first Powerwall home

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Nick Pfitzner and family are the proud owners of the first Tesla Powerwall home in Australia. Nick Pfiztner describes their configuration and the lessons they’ve learnt so far.

Our household had the privilege of the first Tesla Powerwall installation in Australia (maybe the world, they say). It has been a very interesting experience so far, and we’ve learnt a lot about what makes the house tick from an electricity point of view.  I’ve also had the opportunity to discuss the energy generation landscape with several organisations developing similar energy storage technologies.


As a self-described Elon Musk fanboy, I became seriously interested in energy storage for our house after the Tesla Powerwall launch in 2015. I knew about other home storage systems, but mostly associated them with lead-acid systems and off-grid enthusiasts. We had previously got a quote for an off-grid AGM lead-acid system at one point, but we didn’t have the finance or space to make the BSB (big steel box) happen at that time.

However, by late last year with our finances more in order, we decided to take the plunge with the Powerwall. We chose Natural Solar as the installer. They had advertised themselves as the first certified installer of Powerwall in Australia and helped guide us through the options available.

We opted for 5 kW of Phono solar panels with a SolarEdge inverter and, of course, the Powerwall, for a total cost of $15,990 installed.

And add Reposit grid credits

Natural Solar also informed us about Reposit Power, a software package designed to maximise the benefits of home storage for the consumer. In a nutshell, Reposit is a software-based controller for the entire system. It learns the household usage patterns, gathers weather forecast data and interfaces with the inverter to make decisions about import or export of energy based on two important concepts:

Tariff arbitrage. This is the practice of switching to a time-of-use grid tariff and charging the battery at times advantageous to electricity pricing. This may occur when solar PV generation predictions for the next day are poor or where energy storage has been used up overnight. In either case, off-peak power can be imported for use the next morning.

GridCredits. This is an ARENA-supported project to investigate the use of intelligent storage and distribution of power via consumer-level battery systems, with the aim of reducing network infrastructure costs in future. Consumers are rewarded not through feed-in tariffs based on intermittent solar generation, but rather guaranteed power delivery from the battery. When the wholesale market for electricity is especially high, the electricity retailer discharges electricity from the battery into the grid, paying the consumer $1 per kWh.

These two factors could assist with the financial equation, so we figured it was worth the add-on cost of installing Reposit—an extra $800 at the time.

Read the full article in ReNew 137.

Fronius Primo 5.0 Single phase 5kw inverter_1

An inverter buyers guide

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Whether you live off-grid or have a grid-connected generation system, the right inverter can make all the difference. We check out what’s available, where to get them and which one is right for you.

Choosing an inverter may not be the first thing that comes to mind when you’re thinking about installing a solar or solar + battery system. But every one of the 1.5 million solar systems already installed in Australia includes an inverter and, in fact, it can be thought of as the ‘heart’ of the system—if it’s not working, your solar generation is wasted or, if you’re off-grid, you’ll be without power (or at least without mains-equivalent 240 volt power*).


But what is an inverter and why is it so important? In a nutshell, an inverter takes electricity from a power source that produces DC electricity, such as solar panels or a battery bank, and converts it into mains-equivalent power (240 volt AC), ready to be used in your house.
It is important to have a good inverter. In off-grid systems, if your home relies solely on 240 volt power from a stand-alone inverter and the inverter fails, you will have no power, even though it is still being generated and stored. In grid-connected systems, an inverter failure means your solar panels are doing nothing until the inverter is repaired or replaced.

Which inverter for your needs?
The majority of currently installed grid-connected solar systems will be using a grid-interactive inverter. A grid-interactive inverter converts the energy from solar panels into mains power and feeds it into the house’s electrical wiring—no storage is involved. As indicated by the name grid-interactive, these inverters can export energy into the grid, and require a grid connection (or an equivalent 240 volt AC supply) to operate; they can’t operate in a stand-alone capacity.

When you bring energy storage into the equation it gets a little more complex, as the inverter needs to deal with both a generation source (like solar panels) and batteries; and possibly also the grid.

In off-grid systems, a stand-alone inverter can be used to convert the DC electricity from the battery bank into mains-equivalent power to run standard appliances. An inverter-charger is like a stand-alone inverter except that it has a mains voltage level input, which can be used to charge the batteries from the mains or a generator—it is not, however, grid-interactive, so can’t export energy to the grid.

The most complex inverter type is the hybrid inverter, which can feed energy into the grid from either the solar array or the battery bank. Many hybrid inverters can also power the house from the batteries during a power failure, in effect becoming a large UPS (uninterruptible power supply). They can also charge the batteries from the grid.

This makes many hybrid inverters true bi-directional devices, and many, if not most, can handle all of the energy flows in a home energy system. Some can even divert the excess solar energy to a particular load, such as a water heater, replacing the need for a separate device, known as a solar diverter (the SunMate is one example), for this purpose.

Let’s now look at the features of each type of inverter in a bit more detail.

Grid-interactive inverters
Grid-interactive inverters are connected to both the power source (usually a solar array but sometimes a wind or hydro turbine) and the mains power grid. Energy generated by the power source is converted to AC mains power of the correct voltage and frequency and this supplements the power drawn from the grid by the home’s appliances. At times there will be more energy generated than being used and the excess is fed into the mains grid. At these times you will accumulate export credits, although how much you get paid for those depends on your feed-in tariff.

Grid-interactive inverters vary enormously in size, from 10 kW or larger units for big domestic and small commercial systems, down to tiny 200 watt models. Some, known as microinverters, are even designed to be mounted on the back of a solar panel to make the panel itself a grid-interactive module. These are ideal for those who want to start small and increase their system over time, or for systems where the array may be partially shaded—in a solar system using microinverters, each panel is independent of the others and not affected if other panels are shaded.

Read the full article in ReNew 137

For the full tables from this guide in PDF format, click here

Renewable energy courses

Renewable energy courses guide

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We’ve updated our renewable energy courses guide ready for enrolment time. You’ll find the table of courses—from TAFE certificates to postgraduate degrees—here. In the article, Anna Cumming has a look at what’s new in the industry.

IN the two years since we last published a review of the renewable energy courses available in Australia, things haven’t all been rosy for the renewable energy (RE) industry. Months of uncertainty at federal level over the national Renewable Energy Target, funding cuts to climate-related science, and the scaling back of feed-in tariffs for solar generation have all contributed to a reduction in the size of the industry.


The latest available Clean Energy Council (CEC) figures put the number of people employed in the wider RE industry at 14,020 for the financial year 2014–15, down a big 27% from the peak of 19,120 in 2011–121. However, the CEC puts some of this contraction down to a consolidation of the small-scale solar industry to more stable and sustainable levels. It also notes that RET legislation was passed right at the end of the reporting period, and since then confidence has grown: “The mood across the industry is upbeat in 2016, and it is expected that job figures will begin to grow once project development begins in earnest again under the RET in the coming years.”

David Tolliday, Renewable Energy Training Coordinator at Holmesglen in Victoria, shares this feeling. “The initial RE boom [homeowners taking advantage of rebates and premium feed-in tariffs to install solar PV] has passed, and the solar install industry has settled to around 4200 accredited installers—a good sustainable number,” he says. “The big opportunities now are in bigger-scale stuff like commercial solar, and battery storage on grid-connected systems.”

So, how to get involved? For those wanting to get into the industry or upskill, there is a wide variety of training and courses to choose from, from undergraduate and postgraduate university courses in engineering or focused on broader energy strategy, to hands-on solar design and install certificates offered by TAFEs and private registered training organisations (RTOs), and even free online MOOCs (massive online open courses). See our previous RE courses guide in ReNew 129 for a comprehensive look at the types of courses available, prerequisites and typical training pathways; here, we look at what’s new since 2014.

Download the table of renewable energy courses here (130KB).

Read the full article in ReNew 137.


The lowdown on battery technology

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Critical to any energy storage system is the battery itself. So what technologies are available and what are their pros and cons? Lance Turner takes a look inside the technologies available now and what’s in the offing.

IT SEEMS that almost every day a new domestic energy storage system is released onto the market. While manufacturers concentrate on the latest features like compatibility with existing systems, system monitoring, integrated inverters and even programmability, very little is mentioned about the actual storage medium itself.


What makes one battery better than another for a particular use, and which technology should you be looking at for your energy storage system needs? Let’s look at the current options in a bit more detail, including advantages and disadvantages of each, and then look at some newer technologies available now that you may not have seen.


This old faithful is the mainstay of the home energy storage industry. Lead-acid batteries have been in use for over a century and are a tried and proven technology.

They consist of plates made of spongy lead (negative plate) and lead dioxide (positive plate), with sulphuric acid as the electrolyte. During discharge, both plates are converted to lead sulphate, and the discharge reaction produces water which dilutes the sulphuric acid, changing its specific gravity. This change in specific gravity is what allows you to measure a flooded-cell lead-acid battery’s true state of charge using a hygrometer.

Lead-acid batteries have several advantages:

  • reasonable resistance to overcharging
  • lower cost than many other technologies
  • readily available
  • almost 100% recyclable
  • almost all inverters and charge controllers are lead-acid compatible
  • widespread knowledge of the technology in the industry.

They also have disadvantages, including:

  • low energy density, which means high weight per unit of storage
  • can’t be regularly deep cycled without reducing lifespan
  • primary reactive materials are toxic and corrosive
  • can produce explosive hydrogen gas when charging
  • can’t be stored partially discharged without damage—must be fully charged regularly to prevent sulphation (where permanent lead sulphate crystals form on the plates)
  • Peukert effect—effective capacity reduces with increasing discharge rate.

The full article looks at currently available battery technologies in detail, including:

  • lead-acid
  • lithium ion
  • flow
  • salt water
  • metal-air
  • molten salt

Read the full article in ReNew 137.


Finding value in sharing

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Can we find value for both customers and the network in sharing locally generated energy and thus accelerate a transition to 100% renewables? Bruce Thompson and Paul Murfitt discuss the potential in microgrids, virtual power plants and more.

The transformation of the electricity network is certainly now upon us. Years of environmental advocacy, rapid technology advances and shifts in consumer demand are driving an unprecedented shake up of our century-old supply network. With this change come opportunities (and some risks) to harness the value of renewable energy across the grid as we drive towards zero emissions.


Traditionally, Australia’s electricity networks were largely built and controlled by state governments, and operated as central power supply systems managed with two policy imperatives in mind: security of supply and cost-effectiveness. The much-heralded disruption is turning this system upside down, bringing technical and financial challenges along with opportunities.

The big shift to date has been ‘behind the meter’, where there is a clear case for householders and businesses to invest in solar PV to avoid the cost of conventional energy supply. Yet establishing value ‘in front of the meter’—sharing your locally generated energy across the grid—has so far been fraught.

With the tapering off of feed-in-tariffs, owners of solar have been frustrated they don’t receive a fair price for their homegrown generation. On the other side of the fence, network operators have been aggrieved by the need to manage the technical impacts of solar PV and wind while their business model ‘death spirals’ from lower consumption.

Beyond the angst, new models such as microgrids and virtual power plants are starting to demonstrate that sharing solar PV generation and battery storage across the grid can leverage the opportunities and help manage the risks inherent in Australia’s changing electricity sector. For customers, potential benefits include access to wholesale pricing and retail tariffs. For networks, there can be lower costs from local control and load management, particularly if the models can reduce peak demand and avoid the need for network infrastructure augmentation.

Of course, the value of sharing locally generated energy across the grid is dependent on the time of day, the time of year and the location. The key challenge for ‘in front of the meter’ solutions is not only to understand the technology, but also to apply the fundamental principles of supply and demand to determine where the greatest value can be realised.

Read the full article in ReNew 137.


Neighbourly sharing: mini-grid in Mooroolbark, community battery in WA

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Neighbours in the Melbourne suburb of Mooroolbark are set to share their energy generation via a mini-grid in an Australian-first trial run by AusNet Services. Eva Matthews finds out what’s involved.

IN AN Australian first, network provider AusNet Services is currently rolling out a solar + storage mini-grid trial in Mooroolbark, in Melbourne’s east.


Of the 16 homes on the chosen street, 14 will each have between 3 and 4.5 kW of solar panels and a 10 kWh battery storage system installed, with a cloud-based monitoring and management platform to optimise power flows across the mini-grid and to provide demand management support to the network.

The two-year trial was announced in April and was made possible with funding from the Demand Management Innovation Allowance. Participants don’t pay for the equipment and, at the end of the trial, get to keep their panels and inverter (but the control system and battery storage go back to AusNet Services).

As at end August, all houses have solar panels, inverter and battery storage installed, enabling data gathering on energy generation and usage patterns. The control system should be in by end October, which is when testing can begin in earnest. Testing will include deciding when to charge and discharge the batteries, and at what rate, based on current and forecast customer usage and PV generation as well as the network requirements. A single objective (e.g. minimising the overall peak demand on the mini-grid) can be implemented in a number of ways, so they will be developing and testing different approaches. The stabilising device and switching equipment that enable the mini-grid to be islanded (isolated from the rest of the network) will be installed towards the end of this year.

The group of houses will operate as a mini-grid from a control and electrical point of view, but the metering and billing arrangements are unchanged. To enable financial offsetting of one participant’s generation against another’s usage would require different meters to be installed—with a parent meter for the mini-grid and sub-meters for each house—so instead they will be modelling the potential financial effects.

Two households were unable to participate in the trial; however, this will provide fortuitous real-world data for where there is less than 100% opt-in—testing how the mini-grid can serve the energy needs of these houses without having their energy contribution in the mix. AusNet Services’ Distributed Energy and Innovation Manager Justin Harding explains, “Those houses will simply appear as extra loads in the mini-grid. For example, if we are trying to reduce the net demand of the mini-grid to zero at the connection point to the main grid, all houses would need to export a small amount of energy to offset the non-participants’ load.”

Simone and Joel Beatty make up one of the households participating in the trial. When they purchased their home five years ago, Simone says they noticed that a lot of the new houses being built were having solar installed, and it was something they were interested in, but hadn’t been able to afford. So when AusNet Services came knocking on their door with news of the trial, Simone says they were “definitely excited.” As well as looking forward to seeing how it all works, and the impact on their electricity bills, Simone says they have also benefitted from the information provided by AusNet Services—how they can log in to a web portal to monitor their electricity usage and ways in which they can be more energy efficient. She says they have “definitely already altered some behaviours.” And not only has there been an educational side effect of having the technology installed, it has given the neighbourhood something in common to talk about and get excited about. Simone says “everyone seems very positive about it” and adds that friends and family are jealous!

This trial follows a three-year battery storage trial by AusNet Services that tested how residential batteries can reduce customer’s maximum demand for electricity and support the network. Justin Harding says that there will likely be an “evolution of trials” into the future. This Mooroolbark trial has a strong customer learning and technical focus; the next step could be a larger project with more of a commercial focus, looking at how best to structure finances and customer agreements.

Tech used in Mooroolbark mini-grid:

  • 3 kW of panels (JA Solar) per house, except where customers had existing PV systems
  • 10 kWh lithium ion battery storage (LG Chem) per house
  • 5 kW battery inverter (Selectronic
    SP Pro) per house
  • Peak Response Unit (GreenSync) per house—a communications device for optimising power flows, includes 3G modem that talks to the main control system and battery inverter
  • cloud-based control platform (GreenSync’s MicroEM)—runs forecasting/optimisation calculations to enable locally generated/stored energy to be shared between homes, based on the needs of individual houses and the needs of the mini-grid
  • a separate 3-phase inverter and Toshiba battery system from Power Technology to keep the mini-grid stable when in islanded mode
  • switching cabinet with circuit breaker and protection relay to transition the mini-grid to/from the main grid, supplied by EIV.

Aims/benefits of the trial:

  • test how mini-grids can support the network, e.g. to better manage peak demands, reduce risk of system overload, defer capital expenditure
  • optimise value of the assets both for customers and the network, e.g. getting full value from battery storage when customers are grouped and there is one overriding control system versus single households exporting/importing energy to/from the grid
  • better understand household generation and usage patterns to help determine payment structures and tariffs, and test how energy self-sufficient a community can be
  • test potential for an uninterruptible power supply, i.e. where homes can be islanded, either individually or as a microgrid, and stored energy used if the grid goes down
  • investigate the performance of new methods to identify and mitigate electrical faults in a 100% inverter-based supply environment.

Best of both? Community battery trial in WA

A CUTTING-EDGE residential battery trial underway in the new Perth suburb of Alkimos allows residents to generate solar electricity and benefit from access to a ‘virtual storage’ battery system.

Led by local energy provider Synergy, in collaboration with Lendlease and LandCorp, the project involves a utility-scale grid-connected 0.5 MVA/1.1 MWh battery energy storage system located on-site in two shipping containers.

It has a number of aims: to reduce energy bills for participating households and improve network efficiencies by ultimately reducing connection costs. However, the most interesting and important aspect of the trial is Synergy’s ‘time of use’ billing product called the Peak Demand Saver plan.

The plan works by offering a three-part tariff for network energy, with different energy charges for peak daily (4 pm to 8 pm), off-peak day (midnight to 4 pm) and off-peak evening (8 pm to midnight). The time-of-use energy tariffs are designed to encourage households to minimise consumption and maximise returns on their solar PV investment—but without the need to invest in their own battery storage.

This new-style product means Alkimos residents pay a fee each month to have access to the community-scale battery storage. Those who store solar credits during the day draw on them first during the peak daily period, and then for the evening off-peak without incurring any additional costs, in much the same way they would their own battery.  During the day households use their own solar energy.

“It’s everybody’s battery to use. Customers pay $11 per month to use it, and then we calculate their usage over a 60-day billing period,” said Synergy.

“Anything they put into the batteries is theirs to draw on at peak times at no additional charge. And whatever they have left in the battery after the 60-day billing cycle is purchased from them at a 7 cents per kWh [feed-in tariff] rate. Because it is ‘virtual’ storage you can pretend it is your own battery, it’s just your neighbours are pretending it’s their battery too.”

So far, 65 residents have opted to participate in the trial since it began in April 2016 with the aim that 100 households will take part over the four-year trial period. Before residents join the trial, Synergy analyses their historical consumption to ensure the tariff suits their usage patterns.

“However, we’ve already had customers who want to participate even though they are not necessarily going to be better off, because they want to be part of the first shared battery trial in Australia,” said Synergy.

The trial will cost around $6.7 million and is backed with a $3.3 million Australian Renewable Energy Agency grant, and when launching the trial ARENA CEO Ivor Frischknecht said community-scale battery storage held great promise. “A new [housing] development like this might actually need less of a connection, or a smaller connection [to the electricity network]. That means lower costs for those people that are buying new lots and less investment into poles, wires and transformers,” he said.

For more info:

Read more on microgrids in ReNew 137.


Electric vehicles: the market in Australia and overseas

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Bryce Gaton reports on the evolution of government support and global carmakers’ production plans, which together are driving uptake of electric vehicles.

This year has seen a plane fuelled only by the sun travel around the world, a plethora of home electric storage systems come on the market, Australian households with solar PV systems pass the 1.5 million mark and a Tesla Model S travel from Sydney to Broome. Given 2016 is just past halfway through, what else is to come? Is 2016 to become the year that the hoped-for seismic shift in sustainable transport, energy sourcing and use truly begins?


The power to change things is more in our hands than ever before and I will offer examples from around the world that hopefully we can look back on in 20 to 30 years time to say, “We really did start the sustainable transition then!”

Electric cars around the world

Right now, pure EVs with a 300+km range—the ‘Bolt’—are rolling off the Chevrolet production line to arrive in US showrooms in the last quarter of this year.

Similarly, Mercedes, Volvo, Renault, Nissan, BMW, Kia and many other Chinese makers already offer pure EVs in their lineups, and most of these have announced plans to match the 300+km range of the Bolt and Tesla Model 3. Mercedes is releasing plug-in hybrids (PHEVs) and even Jaguar is rumoured to be well down the track in developing an electric sedan and SUV to match the belatedly perceived threat to their core market from Tesla’s Models S and X.

And VW, as part of its mea culpa for the dieselgate emissions scandal, has recently announced plans to heavily move into electric vehicle design and production.

Overall, the trend towards less polluting vehicles continues, with global uptake of EVs and PHEVs climbing at an increasing rate, growing from 45,000 EVs sold in 2011 to more than 300,000 in 2014 (see Figure 1). EVs represent more than 1% of total new car sales in the Netherlands, Norway, Sweden and the USA (closer to 20% for Norway). And in China, 2014 saw 230 million e-bikes, 83,000 electric cars and 36,500 e-buses hit the road.

Read the full article in ReNew 137.


The Pears Report: Post-election shakeout

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Alan Pears takes a closer look at the interesting energy picture post the election.

THE energy picture is now fascinating. Energy (and environment) minister Frydenberg faces some short-term challenges. He must sort out the electricity and gas market messes. Strongly critical senate inquiries and a scathing Productivity Commission report look even more credible after problems with Basslink and South Australian electricity prices and supply, and high and volatile gas prices that have also driven up electricity prices.


The new Liquefied Natural Gas export plants in Queensland face serious financial problems, while creating traumas for industrial gas and electricity users. Powerful energy companies are using their market power to block competition. And greenhouse gas emissions from energy are increasing.

These challenges are compounded by the government’s weak post-2020 energy and climate policies that contrast with its international commitment to cut emissions by 26–28% by 2030.

One change that may help the minister is the separation of the resources sector from energy and environment. This may reduce the influence of some powerful interest groups on management of our energy future—and about time, too.

When industries decline

The financial sector has noticed that the fossil fuel industry is in decline and has responded by reassessing the value of fossil fuel assets—downwards. Once decline is clearly locked in, a number of forces emerge.

First, as ‘higher cost’ mining facilities are sold off at bargain prices, their new owners can cut prices, driving a ‘death spiral’ as lower cost mining facilities face tougher competition.

In the past, large businesses stopped the spiral by buying up smaller, higher cost producers then ‘managing’ their production, so that the demand-supply balance was restored at reasonable prices. Low cost producers might even flood the market with cheap product, to kill off their higher cost competitors, as has been happening in the global oil and iron ore markets.

But a combination of global economic problems and growth of competing solutions is blocking a return to ‘normality’ in the fossil fuel and mining sectors. In our world of disruptive solutions, these competing solutions include energy efficiency, renewable energy, shifts to high efficiency electric technologies, ‘virtual’ solutions replacing physical ones and radically different business models.

This highlights the failure of industries and policymakers to grasp a fundamental that US energy expert Amory Lovins was pointing out in the 1970s. People do not want materials, infrastructure, products or energy: they want services that provide ‘perceived value’, regardless of how they are delivered.

Another major outcome of an industry’s decline is that it loses many of the hidden benefits communities and governments have been providing it. Indeed, demands for more accountability and better performance build, just when the industry’s capacity to deliver them is declining.

As people realise that fly-in-fly-out, highly mechanised mines and power stations don’t create many local jobs—so there won’t be jobs for their kids—and that they pollute and undermine other economic activity, they are much less tolerant of mining and fossil fuels. At the same time, coal seam gas and mega-mines have much more visible impact. Concerns about mine rehabilitation are not being addressed, resources companies are cutting corners and government regulators are failing to hold them to account. Communities are realising they will be left holding the ticking bombs.

At a government level, community pressure and the need to maintain revenues while finding money for mine rehabilitation and decommissioning of old power stations are driving efforts to capture more revenue from fossil fuel and resources industries. In the past, policymakers simply discounted these future costs to negligible levels, but that doesn’t work now. Governments now realise that if the mining industry doesn’t pay, it will hit their budget bottom lines—soon.

Industry advertising campaigns, misuse of statistics and ‘behind closed door’ lobbying have successfully blocked higher taxes and stronger controls in the past. But as an industry’s influence declines, these strategies don’t work as well.

At the same time, it is possible for an industry, governments and communities to maintain denial about unstoppable trends for a surprisingly long time. Indeed, there will be bargains for buyers of some mines, and smart owners can use new technology and creative business models to cut costs, out-compete others and shift risk.

It is also in the interests of existing businesses to try to maintain confidence: not only does each extra month of production produce a lot of money, but it gives them more time to sell off assets to poorly-informed buyers, and to move into new areas of activity.

As they say, change is a time of threat and opportunity.

Where to for industrial, business and home heat?

In Australia, the focus of climate and energy policy has been electricity. It’s a core input to essential energy services, it’s expensive, and it’s responsible for a third of Australia’s greenhouse gas emissions. But provision of heat is responsible for half as much climate impact as electricity, or as much as transport. And often the equipment that uses gas or oil uses a lot of electricity as well. Recent rapid increases in gas prices and price volatility have focused attention on reducing dependence on gas, much of which provides heat.

Australia’s emissions from burning fuels for heat production are broken down in the pie chart above. There is exciting potential to cut these emissions by measures including improved energy efficiency, rethinking industrial processes to reduce the need for heat, and switching from gas and oil to high efficiency electric technologies driven by renewable electricity.

Many households are already moving away from gas to high efficiency reverse-cycle air conditioners, heat pump water heaters and induction cooking. But we need better-insulated hot water tanks and ovens, as well as thermally efficient buildings and smart electricity management systems, to minimise costs and maximise benefits.

In the commercial sector, gas use, mainly for space heating, hot water and cooking, is often appallingly inefficient. Inefficient (often old and poorly maintained) boilers, large losses from pipes and ducts, poor control systems, thermally poor buildings, and inefficient gas cooking provide very large potential for savings. Past low gas prices have led many to be sloppy in their use of gas.

Gas use in industry is often surprisingly inefficient, too. When losses from poorly insulated steam pipes and leaky fittings, ancient and inefficient boilers up to 50 years old and inefficient process equipment are considered, the waste is staggering. Under the Energy Efficiency Opportunities program (shut down by the Abbott government, despite outstanding cost-effectiveness and global recognition), companies were required to develop computer models of the energy and material flows through their processes and to benchmark efficiency against theoretical optimums. Many firms, and their experienced engineers, were very surprised by the scale of inefficiency and the scope for cost-effective efficiency improvement.

Industrial-scale electric heat pumps can now efficiently provide steam using renewable electricity. Improved catalysts are reducing the temperatures of processes. Green chemistry and advanced metallurgy are creating more productive processes, higher quality products and lower process temperatures. Smart controls and monitoring systems reduce reject rates (and the energy wasted producing items that can’t be sold). Improved heat recovery and heat/cool storage increase flexibility and allow previously wasted energy to be utilised.

At the point of use of products, ‘virtual’ solutions are replacing physical products and movement. These include weight reduction and shifting to lower emission impact materials (e.g. engineered timber replacing steel and concrete, and cement made from geopolymers). Increased recycling means lower temperature, less energy-intensive processes replace production of virgin materials.

We are also seeing exciting potential to replace fossil fuels with renewable energy across all combustion activities: ARENA recently funded a study that explored these possibilities.

Across all elements in the supply chain, the multiple benefits of new solutions, ranging from cooler commercial kitchens to lower reject rates and improved staff productivity, amplify the energy benefits.

The big question is whether Australians will capture these opportunities or continue to see themselves as victims of change. Maybe the emerging focus on energy productivity and innovation can help.

Alan Pears, AM, is one of Australia’s best-regarded sustainability experts. He is a Senior Industry Fellow at RMIT University, advises a number of industry and community organisations and works as a consultant.

This article was first published in ReNew 137.


Up front in ReNew: Renewables for all

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AS ITS name suggests, Renewables for All is an initiative to help ensure equitable access to clean energy technology for all Australians “no matter their income or living arrangements.” Set up by the Coalition for Community Energy (C4CE), along with Community Power Agency and Starfish Initiatives, it provides a potential policy framework and business models for governments and agencies to work from, with briefing papers now available on:

  • Solar gardens: the establishment of central solar facilities that enable apartment owners/tenants and others who aren’t able to put solar on their rooftop to have access to clean energy and bill savings.
  • Financing via rates or rents: these mechanisms could allow payback over time by low-income homeowners or renters to councils or homeowners who finance the purchase of these technologies.
  • Community-owned renewable energy projects to increase clean energy accessibility and affordability.
  • Mini-grids and embedded networks: outlining the different approaches and benefits and what policy changes are required to enable them.

For more information on this project and to download all the papers:

Read more news stories in the Up front section in ReNew 137.


ReNew Photo Challenge winner

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From sustainable transport to power systems to forest regeneration, the entries in our photo challenge were inspiring and gorgeous.


It was tough picking a winner among so many excellent entries. In the end, we felt the winner epitomised the spirit of the challenge and of ReNew—a thoughtful combination of action and technology supporting sustainability. Elizabeth Wheeler wins a FLIR thermal camera, kindly donated by Reduction Revolution. Thanks again to all the entries and we hope to use more of these photos in upcoming ReNews!

WINNER: Valuing everyday acts

This is a photo to represent our acts. The way I see it, we can have whizz-bang technologies and buildings, but only by our actions do they actually make a difference. That beautiful double-glazed, highly sealed window on the south side of our house just frames a pretty view; it’s only when I open it that it becomes a passive cooling device and makes a difference to the amount of energy our household consumes. In this image, I wanted to value everyday acts that make a difference. Our shoes are for walking, our GoGet and myki passes are our secondary transport choices, our vegies are from our gardens, our eggs are produced by chooks who subsist mostly on scraps that would otherwise turn into methane, our FairFood invoice represents local food production, and our ATA membership card stands for information and activism. I couldn’t find my FoE membership card, but that should be there too! Of course, they are sitting on a lovely slab of low-embodied energy concrete, which provides the thermal mass to keep our house warmer in winter and cooler in summer! — Elizabeth Wheeler

Read more photo challenge entries in ReNew 137.


Product profile: The laptop that never needs upgrading

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Many people have both a smartphone and laptop, and both devices get upgraded regularly when more powerful versions come along.


The Superbook aims to eliminate upgrading your laptop altogether. While it looks like a laptop, it is actually just a terminal for your smartphone. You download the phone app, plug your phone into the Superbook, and the Superbook becomes your screen, keyboard and trackpad. The app even creates a proper desktop-type environment from the phone, so that it feels like you are using a real laptop.

The great thing is that every time you upgrade your phone, you get a laptop upgrade in the process, without creating the e-waste of the old laptop. Just plug your new upgraded phone into the Superbook and you have an upgraded laptop!

The Superbook also works with Windows tablets, laptops and PC sticks, along with Macs to provide an instant dual-screen laptop.

Basic specs on the Superbook are an 11.6” 720p display (a combined 1080p display and backlit keys upgrade is an option for US$55 extra), 8+ hours of battery life, the ability to charge your phone while working, multi-touch trackpad and keyboard with Android navigation keys, and an optional universal side mount to attach your phone to the Superbook.

RRP: starting at US$99. For more information go to

Read more product profiles in ReNew 137.


Q&A: Wicking beds

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I was very interested in your article on wicking beds in ReNew 135. I have had good success with the Gardening Australia wicking boxes made from polystyrene broccoli boxes. These have PVC tubes filled with soil which go right down to the bottom of the water reservoir. Even if the water level is very low, they are still wicking up through the tube of soil.


My question concerns the beds you showed that had gravel in the bottom. I can’t see how the water would wick up through gravel unless the water level was right up against the geotech. If it only wicks when the water level is near the top, it kind of defeats the purpose of having a wicking bed that is self-watering!

Maybe I’m missing something here. Can you clarify this for me please?



To the best of our knowledge it is undesirable to submerge soil in water—even though it will wick very nicely. Organic matter (such as that found in healthy soil) is food for microbes, both good and bad. When submerged in water, the balance of microbes changes from mostly healthy ones that require oxygen (aerobic), to smelly unhealthy types that don’t (anaerobic—the same goes for your compost/worm farm!).

So by refining the wicking concept, or the materials involved, we’ve found a way to provide the soil with a good balance of moisture and air for healthy soil and happy plants, but prevent organic matter from being submerged in water. You’re right to say when the water reservoir is full, the water touches the geo-textile and is sucked up into the soil via capillary action.

And yes we do use a specific kind of gravel—7 mm bluestone screenings or ¼” minus in the old tongue—for three reasons: it is inert or close enough to it so won’t decompose, therefore it will hold up the soil (!) and still have enough room between the pieces for lots of water.

The screenings themselves actually wick water upward to a certain extent, thus contacting the geotextile fabric and wetting the blanket, even after the water level has dropped below full. In our research we have observed the wicking effect up the screenings themselves to be up to 10 cm.

To round it all out, the enclosed nature of the wicking reservoir, regardless of how much or how little water is retained, creates conditions for humidity and condensation to occur (especially in warm weather when the plants most need that moisture). We don’t know if this has been studied or not, but it does explain why the plants in our wicking beds remain happy even as the water level drops below the extent to which the screenings may wick water up to the geotextile fabric. We think water, even from the lower reaches of the reservoir, condenses on the underside of the geotextile fabric, then wicks up the standard height (30-40 cm) into soil. Hence the fact that the many beds we build in this way all work so well.

Hopefully some university or more scientific types from the ATA membership will set up clear-walled wicking beds and start quantifying this phenomenon so everyone can have a better understanding of what is and isn’t going on.

—Carey Priest, Very Edible Gardens