Current Issue

ReNew Editor, Robyn Deed

ReNew 131 Editorial – Electric avenues to more sustainable transport

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Planning this issue started with many conversations about electric vehicles (EVs).  “I saw an ad for one the other day,” someone said, “but I can’t remember what it was called.” Someone else said, “Are there any available in Australia?” Several someones asked, “Do you mean the Prius?” Full marks to Toyota for good marketing of the Prius (even though it’s a hybrid rather than an EV), but Australia now has several electric or plug-in hybrid electric vehicles (PHEVs) to choose from.


It is early days, as the sales show (see our article on the EV market in Australia), but perhaps, just maybe, we are at a turning point. It’s happened in the USA, with sales of EVs and PHEVs accelerating since 2011. Our author suggests that perhaps 2015 will be the year things start to change here.

In the USA, and even on a small-scale here, the idea of smart charging (with the timing of EV charging controlled by the grid to avoid peak times) is moving from research to trials. Using your EV as storage is also getting attention, for providing emergency power or grid backup. Read about these in ‘Your EV’s Other Life’.

The latest in our ‘Know your renewables’ series focuses on EVs too, getting under the bonnet to explain how they work, behind the wheel to see how they drive, and discussing the nitty gritty of how to manage charging and maintenance (in answer to the latter—easily, with much less maintenance required than a standard ‘fossil’ car, and many EVs enabled for remote support via their internet connections).

We also talk to owners of electric cars, motorbikes and e-bikes to hear their stories of how they came to the world of EVs. Some have had the ‘EV grin’ forEVer, but others are new to the idea. For all of them, it’s part of a wish to reduce their transport-related emissions; for many, there’s also joy in the new technology (Tesla Model S owners put your hands up); for one, it’s been on his ‘bucket list’ for a while!
Of course, better public transport, better planning and bike-friendly roads can go a long way to reducing our emissions as well. We also look at electrifying some of these options, with electric buses, motorbikes and bikes. We even look at electrifying planes.

We don’t discuss in detail here the question of the difference in emissions between electric vehicles and petrol-powered cars, covered previously in ReNew 120. That equation rests on how dirty the electricity generation is, but the balance can be swung towards the green through solar PV and GreenPower, whereas petrol-power can never be made clean.

It’s not just about EVs this issue. We also cover a household living their off-grid dream with a bike shop, holiday rental and home in WA, examine solar financing, shine a light on the problems commonly found in energy assessments and cover three DIY projects, including the intriguing open-source Open Sprinkler water reticulation controller. Plus our buyers guide this issue is an update of our very popular guide on batteries for household renewable energy systems. Enjoy!

Robyn Deed
ReNew Editor


ATA CEO’s Report

One of the most rewarding aspects of working at the ATA is being able to make someone’s day. Like when we give advice to a person who’s doing something sustainable in their home.

Recently we received some lovely feedback from Lauren, an ATA member who was looking to install an off-grid solar system on her property in regional Victoria. She had spent months researching and getting quotes from installers but was unable to make a decision on the best option. After a one-hour consultation with one of our experts, she has gone ahead and bought a system. Lauren said: “You quite quickly helped me to crystallise my needs in just one hour, something I had been chipping away at for over four months. If I had my time again I would have signed up, become a member and made an appointment with you straight away.”

Empowering people with quality information so they can make informed choices is the ATA’s mission. We achieve it in a variety of ways including the ATA member and consultancy advice service, information in ReNew and Sanctuary magazines, e-books and other online resources such as the Tankulator ( and Sunulator ( There are also the face-to-face services we provide at our Speed Date a Sustainable Expert events, and our presence at home shows and other community events.

As existing sustainable technologies and solutions evolve and new ones emerge, the ATA will continue to play a key role as an independent voice helping people make sustainable choices.

Donna Luckman



The Australian electric vehicle market

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Bryce Gaton explores what’s available now and what may be added soon to the Australian electric vehicle offerings.

Around the world, electric vehicles are moving beyond the realm of frustrated early adopters building their own to showroom doorstoppers providing viable alternatives to the fossil (fuelled) vehicle. With products coming out of most of the major manufacturers’ factories, there are now almost too many options for the would-be electric vehicle buyer to select from!


Unless, that is, you live in Australia…so why are we waiting?

What’s available overseas

There are so many electric vehicle options available overseas that it’s necessary to list them by vehicle segment rather than by manufacturer. Table 1 (in ReNew 131) shows a selection of electric vehicle (EV) and plug-in hybrid electric vehicle (PHEV) models that are currently available around the world (with the exception of the Tesla Model X which is expected to be released this year). They’re grouped by Euro NCAP segment, a designation that defines the type of vehicle, such as mini, compact, mid-size, etc.

Australian EV/PHEV offerings

The bold vehicle names in Table 1 are those currently on offer, or able to be bought secondhand, here in Australia in 2015. It’s a bit sad really, given the plethora of offerings elsewhere. However, combining this data with Table 2, we can see that five of the world’s six top-selling EV/PHEVs are available here, with the sixth offering in Australia (the i-MiEV) still in the world top 20. So at least it can be said that Australia does get the top EV/PHEV offerings. On the other hand, the EV/PHEV sales figures for Australia (in Table 3) are far less encouraging.

With such low EV and PHEV sales in 2014 in Australia, it is not at all surprising that the major vehicle manufacturers are seemingly uninterested in bringing additional models to split the market further.

It could also be argued that the manufacturers have done very little to promote EVs in Australia; however, that appears to be changing in 2015. With recent advertising campaigns for the Leaf, Outlander PHEV and BMW i3, as well as some canny marketing by Tesla, this year may see a surprising result for EV sales in Australia.

Read the full article in ReNew 131.

know your evs

Know your renewables: All about EVs

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Electric vehicles are evolving at a rapid pace and look set to displace fossil fuel vehicles in the not-too-distant future. Lance Turner looks at some of the basic concepts and terms you might come across when discussing EVs.

For almost 100 years, the personal automotive industry has been dominated by internal combustion engine (ICE) vehicles, burning either petrol, diesel or LPG. As an alternative to ICE-powered vehicles, electric vehicles (EVs) have been nothing but a novelty to most people, purported to lack range and power, making them unsuitable for most people’s uses.


However, all that is changing, with EVs making steady inroads into the global car market, and even (slowly) here in Australia. The shift in thinking started with the introduction of hybrid electric vehicles (HEVs), such as the Toyota Prius and the Honda Insight. With these vehicles, especially the Prius as it can run in all-electric mode at lower speeds, the general public started to experience some of the advantages of HEVs, such as reduced exhaust pipe emissions, almost silent driving and greatly increased efficiency.

But hybrids have a number of drawbacks. Firstly, as they have both an electric drivetrain and an internal combustion engine, they are more complex than either straight ICE vehicles or EVs. Secondly, although there is an electric drive component to their drivetrains, hybrids still gain all their motive power from fossil fuels (conventional hybrids can’t be charged from the mains grid, and they usually have quite small battery packs), so they are still an unsustainable form of transport, despite having lower emissions than equivalently sized ICE vehicles. The world’s oil reserves will last longer with hybrid vehicles, but will still eventually be exhausted.

As the public’s acceptance of hybrids grew, there was the desire for vehicles that had the advantages of EVs, without the limitations. Hence, the plug-in hybrid electric vehicle (PHEV) was born. These are similar to a hybrid but they differ in two important ways—they have larger battery packs that can be charged directly from mains power, rather than from the on-board ICE, and their electric motor is designed as the primary motor. This means that they can be driven as an EV until the battery is almost flat (or another battery level setpoint), at which time the ICE starts up and provides electricity to charge the battery and power the electric motor.

For owners who do many short trips, PHEVs can run purely on electric power and may never need to use the petrol backup at all. The Holden Volt is an example of such a vehicle, and the most recent incarnation of the Volt has an electric-only range of around 80 km, making it suitable for all-electric use most of the time.

However, there is a need to uncouple personal transport from fossil fuels completely to reduce emissions from this sector, and given that alternative fuels such as ethanol and hydrogen often produce as much CO2 in their production as they save, the only realistic way to achieve this currently is to make cars completely electric, removing the internal combustion engine option altogether.

Read the full article in ReNew 131, covering how an EV works, energy recovery from braking, driving an EV, why buy an EV, battery lifespan, cost and materials, charging and more!


Everything’s going electric: Planes, buses and bikes

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It’s not just cars that are going electric. Lance Turner takes a look at other transport options that are ditching fossil fuels, including electric bikes.

While electric cars seem to get all of the publicity, there’s a lot more happening regarding the electrification of transport than just cars.

Personal transport—motorbikes and bicycles


On the personal transport side of things, motorbikes are set to become the next big EV thing, and we have already started to see the move to electric two-wheelers here in Australia. Quite a few low-powered commuter type electric scooters have been on the market for a while, but for anyone looking for a replacement for their fume spewing motorbike, there haven’t been many options—until now.

Vehicles such as the Australian-made Catavolt S6 and Zero SR from Zero Motorcycles in the USA have shown that electric motorbikes are now viable replacements for all but long-distance touring bikes. For example, the Zero SR with Power Tank long-range battery has city/ highway/combined ranges of 298/151/201 km respectively, a top speed of 164 km/h and a zero to 100 km/h time of under four seconds. Note that with electric vehicles, city range is often better than highway range due to the lower air friction losses and the opportunity for energy recovery with regen braking. This is the opposite of ICE vehicles, which are very inefficient in stop-start travel and reach much greater efficiency at a fixed speed.

The Catavolt S6 is available online at www. while the Zero range is available from a number of dealers here in Australia (see www.zeromotorcycles. com/au/locator and

While on the subject of two wheels, electric bicycles have been a popular choice for many years, and there is a wide range available. Indeed, most bike shops have at least some models, but it’s important not to cut corners and buy the cheapest bike you find. There’s a price to pay if you want a robust bike with a reliable battery and motor—buying a cheapie might leave you stuck with a failed battery in only a year or two, meaning an expensive unscheduled replacement. There are numerous good quality e-bikes available, so talk to your local bike shop and see what they recommend. For more information, see the Electric Bike Buyers Guide in ReNew 123.

Read the full article in ReNew 131, including more on buses and planes.


A battery buyers guide

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The battery bank in a stand-alone or backup power system can make or break the system. Lance Turner examines what to look for in a battery bank and how to get the right battery for your needs.

An extract of the article is below, or read the full article in ReNew 131.


You can also download the full table of manufacturers, suppliers and their batteries.

Article extract:

As more people look to go off-grid due to the ever-increasing cost of electricity bills and the unreliability of the grid in some areas, the market for energy storage systems is set to expand massively in the next few years. That’s not to say there aren’t options available already—there are plenty, for both off-grid and on-grid use.

There are two main approaches to energy storage: you can buy the required number of individual batteries or cells and have them installed and connected together on-site, or you can buy an integrated ‘storage system in a box’, containing batteries, safety equipment such as fuses and disconnects, and possibly a charge controller or other equipment.

As we looked at integrated storage systems in ReNew 128, this guide looks mainly at the first of these options: buying batteries or cells for assembly into a large battery bank. We also don’t cover batteries for electric vehicles (EVs); see our All About EVs article on p. 38, for a discussion of batteries for EVs.

Battery selection is critical

Arguably the most important part of any renewable energy system involving energy storage is the battery bank. All other parts of a system can be upgraded or added to quite easily, but if you select too small a battery or one not suited to your needs then your system performance, and the battery’s usable life, will suffer. Unfortunately, the battery is the component most likely to be specified incorrectly, either due to a lack of understanding of how batteries perform, or budgetary constraints—the battery bank is now the most expensive single component in the average stand-alone power system (SAPS).

Battery requirements

Batteries are designed for specific applications. In this article, we look at batteries suitable for use in renewable energy systems, either off-grid, in stand-alone power systems (SAPS), or on-grid, in a grid-connected system with storage for either load shifting or backup power.

Over time, and with changes in technology, the requirements for domestic energy storage systems have changed quite considerably. Once common, 12 volt DC systems are now mainly found in caravan and camping situations, though small SAPS systems may still run at this voltage.

Current homes instead usually run AC-based systems. They have 24 or 48 volt (or even 120 volt) DC power systems with inverters to convert the power to 240 volts AC, and use efficient AC appliances.

Such systems need large capacity battery storage to cope with the high surges required to start the motors in appliances such as water pumps and vacuum cleaners, and ensure long battery life through shallow discharge of the batteries. Generally speaking, the deeper a battery is regularly discharged, the shorter its lifespan will be.

Useful characteristics for batteries in renewable energy systems are:

  • long life under a continual charge/discharge regime
  • ability to withstand numerous deep discharges over the life of the battery (e.g. in winter when it may need to be discharged more deeply)
  • low maintenance requirements
  • high charging efficiency; some energy will be lost when the batteries are charged, but the lower this is, the better
    ability to perform over a wide temperature range.
  • low self-discharge; all batteries slowly discharge themselves over time, but the lower this is, the better.

Common renewable energy system battery types

The most common chemistry used in household energy storage systems is still the lead-acid battery. These have been around for more than a century and work well provided that the appropriate size and type are selected, and they are used and maintained appropriately.

As demand for more advanced energy storage grows, there has been much focus recently on lithium-based batteries. For household energy systems this generally means lithium iron phosphate (often called LiFePO4 or even just LFP) chemistry, which has seen considerable advancements in the last few years, with a steady decrease in cost as the scale of manufacturing has increased.

Nickel-cadmium batteries were used for a period in stand-alone power systems. However, their high cost and relatively high toxicity means they have all but disappeared. A related but much safer chemistry is the nickel-iron battery.

Other battery types found in commercial systems, though generally not used in domestic-scale systems, include flow batteries, sodium-sulphur batteries and even flywheel batteries.

Lead-acid batteries
Lead-acid batteries consist of lead and lead-sulphate plates suspended in a sulphuric acid electrolyte. They are a reliable and well-understood chemistry that is relatively forgiving to mild overcharging, although over-discharging can impact lifespan considerably.

In years past, the most common type of lead-acid batteries in household power systems were flooded cell types. At the time, these offered the longest life and best value for money over their lifetime.

However, in more recent times there has been a trend towards prioritising lower maintenance requirements, resulting in an increasing number of systems being installed with sealed lead-acid battery banks. With these, you no longer need to check cell electrolyte levels, and the corrosion by acid that occurs with flooded cells is virtually eliminated.

Sealed lead-acid batteries come in two main designs—AGM (absorbent glass mat) and gel cell. Gel cells have their electrolyte as a gel to prevent spillage and stratification (where the acid density of the electrolyte varies from the bottom to the top of the cells), while AGM batteries have liquid electrolyte, like flooded-cell batteries, but it is absorbed into fibreglass separators between the cells to provide the same benefits as the gel type. Either type can usually be mounted in either an upright or sideways orientation.

Lithium batteries
While lead-acid chemistry is still the mainstay of the renewable energy storage industry, this is steadily changing, with other battery chemistries such as lithium potentially offering considerable advantages over lead-acid batteries.

Lithium iron phosphate (LiFePO4) batteries have higher storage densities (more energy can be stored in a battery of a given volume), greater power densities (smaller batteries can produce greater instantaneous power outputs), much better charging efficiency and longer lifespans than any lead-acid formats.

They can be more expensive to purchase initially, but this is rapidly changing as the push for lower cost batteries for electric vehicles as well as domestic energy storage systems has spurred on many manufacturers to reduce prices and increase availability.

In addition, due to the longer life and higher efficiency of lithium cells, and the fact that their capacity is not affected by discharge rate like lead-acid cells, enabling lower capacity banks to be used compared to lead-acid, lithium batteries are already a cost-effective option when total cost of ownership is considered. While lithium batteries are still a relatively small segment of the domestic energy storage market, this is set to change in the next few years.

Lithium batteries must have an effective battery management system (BMS). This enables each cell in the battery bank to be individually monitored when charging and discharging. Overcharged cells and cells discharged below the minimum voltage point can fail, so a good BMS is a must.

Buy ReNew 131 to read the full article which includes:

  • other battery technologies
  • battery specifications (capacity, battery formats, voltage, battery charging efficiency, battery life)
  • sizing the battery bank for a stand-alone system
  • maintenance
  • battery sustainability
  • safety and a home for your batteries
  • battery bank do’s and don’ts
  • secondhand batteries.


ev delaware

Not just transport: Your EV’s other life

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Electric vehicle by day, powering your home by night? Kristian Handberg explains how EVs could help in the energy storage equation.

For those with solar PV systems getting paid next to nothing for their surplus generation, the day is fast approaching when they might store this energy for later use. But should they use a stationary battery or an electric vehicle?


The situation for stationary batteries is changing rapidly. Battery costs are coming down and electricity market rules are changing to accommodate new business models for energy sellers who use storage1. Solar homeowners may soon be offered energy supply agreements that include a battery located on their property but owned and operated by their electricity retailer2. Homeowners will see the benefits via reduced electricity costs and supply agreements that avoid the complexity and risk of owning and operating a grid-connected energy storage system.

Right now, however, solar homeowners must deal with these challenges themselves. High upfront costs and long paybacks, risks associated with new technology and warranty commitments, and complicated energy management strategies are all reasons to delay on battery investment or look for alternatives.

One of these alternatives may be to use an electric vehicle as storage—if an electric car works for your transport needs, why not also use it to get better value from your solar investment.

While vehicle charging can be managed in line with solar production, at present there are no electric cars in the Australian market that allow charge to be extracted for other uses. Equipment is sold in Japan that allows emergency backup power to be obtained directly from the vehicle (see box on this page), along with vehicle-to-home (V2H) charging solutions that can provide backup and solar PV optimisation. Combining a standard charger with a bi-directional inverter (supporting both the vehicle charging and discharging) and an energy management controller, these V2H systems currently cost around $1000/kW (or around $4000 for a 16A V2H unit, as compared to $500–$1000 for a standard 16 A charger).

These costs can be expected to decrease as the technology improves and the plug-in vehicle market grows. Driven by these changes and the results of trials currently underway, the analysts Navigant are forecasting that V2X-enabled vehicles (vehicles which support discharging activities) will be launched internationally in 2016 alongside improved V2H systems3.

As the technology evolves, there will be opportunities for householders, within the context of wider considerations.

Read the full article in ReNew 131.

solar finance

Solar financing

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Andrew Reddaway considers whether there are savings to be found in financing your solar install.

“Save money from day one”—sounds pretty good doesn’t it? Several companies offer to finance your solar install, claiming that savings on your electricity bill will outweigh repayments so you will be better off. But how far ahead might you be?

Solar financing options


For this article we looked at several options to pay for a solar system:

  • pay upfront
  • redraw from your mortgage
  • unsecured finance
  • Environmental Upgrade Agreement (EUA)
  • Power Purchasing Agreement (PPA).

Pay upfront

This option is only available if you have sufficient savings to draw on. The only finance-related cost is the ‘opportunity cost’: if you hadn’t spent the money on a solar system, you could have invested it instead and made a return. For example, you could have invested in a term deposit earning 3.7% per annum (before tax).

Redraw from mortgage

Home loans are secured by your house so the interest rate is low e.g. 6% per annum.

Unsecured finance

Many solar installers will offer finance, typically from an external funder. Separate finance is also available from financial institutions. If the loan is set up as a lease, the lender may be responsible for maintenance. Repayment amounts, durations and fees vary considerably, but the deals we’ve seen have effective annual interest rates ranging from 10% to 28%. Watch out for apparently cheap finance attached to an inflated system price, or direct debit fees that continue after you’ve repaid the loan.

Environmental upgrade agreement

Currently EUAs are offered by a few councils through targeted programs. The council lends you money (from an external finance organisation) and you pay it back via a special charge on your council rates. If you move out, the repayments are taken up by the new owner. This allows for cheap finance with long repayment periods.

Power purchasing agreement

Under a PPA you do not own the solar system. Instead its generation is metered and the solar installer bills you; for example, they might bill you 21c per kWh. You still get a bill from your grid energy retailer, but the total of the two bills should be less than your previous bill. There are several variations of PPA so watch out for issues such as moving house or roof damage. Also, what happens when you’re not home and the solar system is exporting to the grid? If you still have to pay the installer, then the solar system may actually be costing you money at those times.

Read the full article in ReNew 131.


home assessments

100 home energy efficiency assessments

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Simple discussions with householders can shine a light on common energy efficiency problems. Tim Forcey shares the process and lessons learnt in a recent round of council-funded home energy assessments.

In late 2014, a local council in eastern Melbourne committed to deliver 100 home energy assessments as part of a sustainability outreach program. They contracted Positive Charge—a social enterprise set up by Moreland Energy Foundation Ltd—to do the assessments over a six-week period, and I was one of the two assessors. It was interesting to observe which residents took up the offer, what they needed help with, and to consider how effective the assessments were. This article is an attempt to share what we learnt.


Over 90,000 people live in the council area where this project took place, so 100 free consultations were not going to change the world, but perhaps would be a step to something bigger.

Such home energy assessments have been done for many years in many ways. Some have been done informally by volunteers— neighbours helping neighbours. Some have been done within the strict requirements set by federal, state or local governments. Some have been done at no cost to the resident, while others have involved thermal imaging cameras and blower doors and cost more than $400. Some energy retailers have trained up assessors and then pulled the plug on the whole thing without a single assessment being delivered.

Getting the word out

This service was offered at no charge to residents, but council advertisements noted that assessments were “valued at $250”. Residents were informed about it via council newsletters, notices in the local paper, flyers sent out by politicians in the lead-up to the Victorian state election and a stall and ad hoc spruiking at a local community festival. When residents responded with a phone call to Positive Charge, a member of the team scheduled a one-hour assessment.

The process

One thing we learned fairly quickly was that we shouldn’t call them ‘assessments’; ’consultations’ would be more acceptable (and more accurate). As I walked through a client’s front door, they immediately asked me, a bit defensively, “So, what are you going to assess?” To which I replied, “Nothing! Let’s talk about whatever you want to talk about.”

Upon arrival at a client’s residence, I’d first locate a table where we could work, with enough room for my binder full of photos, reference materials and fact sheets. I’d then ask the homeowner or tenant what they wanted to discuss. During the booking phone call, Positive Charge staff had usually tried to

gather some of this information, so residents were already focused on what they wanted to achieve from the consultation.

I would then write down what the resident was saying, for my own use over the course of the hour. Next, I would ask the resident to also grab a pen and a paper so they could take notes or jot down ideas. The aim of the hour was simply to come up with some ideas and actions in a loosely prioritised list, rather than there being an official follow-up report.

Sometimes what they wanted was about ‘bang for the buck’. For some, it was about improving their desperately uncomfortable homes; achieving positive environmental outcomes was usually in the mix as well.

Next, I would have a quick squiz around the home, asking things like, “How is the house on a cold winter day, or during summer heat waves?” We would check out the space heating and cooling systems, their means of water heating, how many fridges were hiding in the garage, the extent of window treatments, the style of lighting, the air-tightness of the house and so on. Then, back to the table—a quick look at gas and electricity bills—and then it was time to start the list!

Read the full article in ReNew 131.


Off-grid WA

Off-grid in WA

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Jai Thomas describes his parents’ journey to off-grid living.

In 1993, my parents, Sherry and Barrie Thomas, made a life-altering decision to pursue a ‘tree change’, long before that concept came into being. Finding a property in the beautiful Preston Valley of south-west Western Australia, their dream was of a future in the emerging eco-tourism industry, based around their love of the bush and of bicycles. With four children under 10, some might say it was a bold vision!


Twenty-two years after purchasing 100 acres of “rate-absorbing, unpowered, unwatered bushland”, and many ups and downs, they now look back on their journey with pride and are happy to share their story of ‘riding the trail’ to sustainable living.

The early days

Life on the Preston Valley property started in a tent at weekends. With a six-day bike shop business in town and four children in primary school, even just getting to the place one day a week was a challenge. Then, the retail slowdown of the mid-90s hit the bike business hard. With both time and finance in short supply, Sherry and Barrie decided to start small, with an owner-designed and owner-built weekender cabin.

In 1995, with a site selected, Sherry designed the 9 m x 5 m two-storey cabin with an open-plan kitchen and lounge room downstairs and loft bedroom upstairs. They used Colorbond and Hardiflex cladding on recycled jarrah stud walls, built around jarrah poles sourced from the property.

Even though the cabin was small in footprint, the one-day-a-week approach meant progress was painfully slow. Lessons were plentiful. The jarrah used in the wall frames was so hard it was virtually impossible to hammer a nail without a pre-drilled guide hole; as a result, the decision was later made to use pine frames when building the main house! They scoured all over for construction materials—from demolitions, discards after renovations and saleyards. Only rarely, given their financial situation, did my parents purchase new.

Their first stand-alone power system (SAPS), a 12-volt system featuring just three 85 W panels and 2.4 kWh of deep-cycle lead-acid batteries, almost broke the budget before the building began. Barrie, an electrician by trade, wired in 6-volt bicycle headlights, the very first LEDs of their breed, in series of two. Fitted to old sets of bicycle handlebars mounted on the walls, this gave them (characterful!) lights at night, but nothing more.

The old Honda diesel generator worked hard during construction, and after 12 long years the cabin was finally born, albeit not quite finished.

Read the full article in ReNew 131.

Alan Pears

The Pears Report: Electricity industry potential

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The electricity sector is broadening, with yet more complexity in store. Alan Pears examines the opportunities and risks.

Our definition of the electricity sector has broadened in recent years, but it will become even more complicated. If we step back and look at the fundamentals, we can see why. As I’ve noted before, people (and businesses) don’t want energy (or electricity)—they want energy-related services, such as lighting, cooking, heating, clothes washing and internet.


The overall costs of an electricity-related service are comprised of both supply-side and consumer-side costs. These include:

  • supply-side costs of the electricity used, reflected in the retail price and fixed charges for the electricity
  • consumer-side costs of electricity supply infrastructure, such as wiring, on-site generation, storage and electricity management systems
  • consumer-side costs to purchase and install energy-consuming equipment
  • ongoing consumer-side costs of maintenance and ‘consumables’, such as provision of cable TV and internet services, repairs, detergent, etc.

Estimating the consumer-side costs

Since no one else seems to have attempted to estimate the costs on the consumer side of the meter, here’s a try.

The 2010 ABS survey of household expenditure on goods and services shows average weekly household energy bills were then $32.52 (more like $40 to $50 now). But the weekly average purchase and non-energy-related operating costs of appliances, IT and AV equipment, internet and phone amounted to $93.26. Of this, $36.78 covered appliance purchases and $44.97 covered the payments to providers for internet, pay TV and phone usage.

So, in 2010, direct energy costs comprised only about a quarter of the total household cost of providing energy-related services (excluding spending on building features such as insulation, house design and draught proofing, but still including heating and cooling appliances and running costs).

We should also keep in mind that each appliance purchase locks in energy use for a decade or more; $1000 spent on a new fridge can lock in $1000 of energy waste over 15 years if you choose ‘worst on market’ instead of best.

The big money for businesses and the big savings for consumers are not in supplying energy, but rather in the provision of smart, energy-efficient and renewable energy appliances, equipment and associated services on the consumer side of the meter.

More profit in retail electricity

Based on the Bureau of Resources and Energy Economic’s 2011–12 energy data and my best guesses at electricity prices for each sector, residential consumers provide 43% of electricity revenue, but use only 28% of the electricity. Business retail electricity consumers pay around 45% of total electricity costs while using around 35% of total electricity. This reflects the high network usage and administrative costs for the small consumers in these sectors.

Despite several hours of searching, I couldn’t find out how much industry pays for electricity and gas—from publicly available information (!)—so these numbers are rough. But it seems that a profitable electricity business needs to focus on retail customers (residential and business), not big industry.

The potential profit margins, and the number of places in the supply chain where margins can be added, are greater for retail customers. In contrast, big industry is quite capable of negotiating low electricity prices—or even subsidies.

Opportunities—and risks

There are both big opportunities and risks for the electricity industry in this complex retail space on the consumer side of the meter.

Businesses selling on-site energy efficiency improvement, generation and storage to retail customers compete against high electricity prices—unless the electricity retailers can fool regulators into allowing them to charge high fixed fees… So, it’s not surprising that PV businesses have targeted residential and, increasingly, commercial customers. It’s also not surprising that attractive financing packages and buyer-friendly installations are important.

Broader issues such as what services customers really want, trust in providers, packaging of overall deals and social and environmental impacts of options will increasingly influence decisions that drive electricity demand.

Potential for the appliance and building industries

Many markets, including appliances, building, property, installation, insurance, IT and telecommunications, will influence the future of our electricity sector, as much as or potentially more than the energy industry itself. Players in these markets understand customers better and can move very fast. They are bigger and more powerful than the energy industry. But, at present, they are fragmented.

Once the appliance industry focuses on energy issues, they will see many opportunities. For example, adding built-in micro-storage and smart controls to an induction cooktop, dishwasher, oven or air conditioner cuts installation costs by avoiding the need to upgrade wiring capacity within a house and/or offers better quality services. This ‘added value’ will offset the extra cost—and help cut peak demand costs. Indeed, such micro-storage may also help overall household management of electricity.

There is potential for an appliance manufacturer to partner with a major builder and renewable energy business to offer a house full of high-efficiency new appliances, ‘smarts’ and PV system for ‘free’ (actually paid off via your mortgage) in a new home package. Some banks could even offer a discounted interest rate for such a home.

The appliance manufacturer would gain an ongoing relationship with a household to leverage future sales and get valuable feedback on appliance performance, reliability and user behaviour. The builder would save on wiring and gas plumbing costs, while offering home buyers a very attractive package. This model could easily roll out to low-income households.
Meanwhile, the traditional energy sector, protected by outdated policy frameworks, looks at the supply side of the meter, where scope for profit and customer benefit is much smaller.

Where to on energy policy?

State and local governments, reflecting what I call ‘competitive democracy’ are filling the vacuum created by bizarre national government policies, by supporting renewable energy projects and, in some cases, energy efficiency, as they seek electoral popularity. In some cases, concern about climate change even drives policy!

Global factors are driving closure of Australian energy-intensive industries that are too small to compete globally or rely on outdated technologies. Indeed, free trade agreements and other government policies are making this problem even worse for energy suppliers by driving industry closures.

Global oil, coal and gas prices have fallen —driven by a complex combination of excess (but high cost) supply and lower-than-expected demand. It seems that many economies really are decoupling energy growth (and greenhouse gas emissions) from economic development. And, with asset values of fossil fuel producers and traditional energy utilities crashing, their problems will grow as investors shift their money to safer options. Already, those who have not yet divested from fossil fuels have lost a lot of money.

Existing Australian policies and regulatory requirements, despite being fairly weak by world standards and poorly enforced, are driving step changes in new building and appliance efficiency. Product manufacturers (mainly from overseas) are providing more efficient products because of global demand. And business must respond to higher electricity and gas prices by improving energy efficiency.

So, no government can provide policy certainty in energy. At the same time, declining demand (due partly to energy efficiency improvement) and increasing support for renewables at many levels, means excess supply capacity will remain unless incumbent energy businesses close down a lot of existing obsolescent or high-production-cost plants. And if this happens, governments will face criticism for allowing it, given that it will likely increase consumer energy prices!

Meanwhile, the Australian government and its policy makers are preparing our next Energy White Paper. The Green Paper, published in late 2014, provides little basis for this policy document, as most of it was simply irrelevant to the fundamentals of the situation (see my submission at Of course, official government energy policy is usually out of touch: its main aim seems to be to support ongoing economic growth (based on past directions) and reassure incumbent industries and their investors. So it will be interesting to see what the White Paper actually says, and what government actually does.

I don’t know of anyone who can predict where this will lead. But it is a risky time for owners of large fossil fuel assets and investors in any large energy project that takes five years or more to implement. So, my money is on modular and smart solutions that can generate cash flow quickly, through incremental rollout. S

Alan Pears is one of Australia’s best regarded sustainable energy experts. He teaches part-time at RMIT University and is co-director of Sustainable Solutions, a small consultancy.

This article was first published in ReNew 131.


Building a solar reticulation system

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Martin Chape explains how he replaced a power-hungry bore pump with a low-cost solar unit and automated his watering system at the same time.

For some time I’d wanted to get rid of my power-hungry three-phase mains-operated bore pump, used to water my garden from the aquifer beneath my house. This forms part of a bigger plan to move all my 240 volt appliances off-grid. The large power drain of the three-phase bore pump would almost double the size of the inverter I’d need to go off-grid, even though it only gets used in summer, and then for just 15 minutes, three times a week.


So, I decided to replace it with a 24 volt DC bore pump run from solar PV. This pump fills a rainwater tank from the bore, using a float switch to turn the pump off when the tank is full. The resulting system can be completely automated and independent of utility-supplied water and electricity.

The pumps and tank

I ordered a 24 volt DC multistage submersible bore pump (a Kerry M243T-20) from a dealer on AliExpress, for US $178. This pump is class IP68 (fully dust and water tight; see, has a 25 mm outlet pipe, can pump to a head of 20 metres at 3000 litres per hour and draws 384 watts (at 24 volts that’s about 16 amps).

While waiting for the solar pump to arrive I removed the existing bore pump and sold it for $500. Using that as my starting capital, I hunted down a 2500 litre poly rainwater tank through Gumtree and, with the help of my neighbour, installed it on a brick and concrete foundation. I had first considered building an elevated tank stand, to provide water pressure from the height, but decided against this after reading a story of a home-built stand collapsing on someone. I also would have needed local government approval.

So the tank ended up on the ground and I purchased a second pump to move the water out of the tank to the garden. It’s a 24 volt DC submersible pump (US$35 from another AliExpress seller) with a single impeller (the spinning rotor that pushes the water), a 25 mm outlet pipe, 12 metre head capacity and it draws 120 watts. Oddly, it claims a flow rate of 8000 litres per hour compared to the 3000 litres of the bore pump.

[Ed note: Cheap devices bought directly from China can vary in quality; checking the seller’s feedback score and comments can assist, but as Martin’s experiences show, there can still be issues.]
When this pump arrived from China it had been damaged in transit so I ordered a second one and then contacted the supplier. The supplier was very good and supplied parts which I used to repair the first pump, which is now in my shed as a spare.

The solar bore pump then arrived and with the help of a friend I soon had it installed in the bore. It seemed to work initially, but then stopped after just 10 minutes.
I contacted the supplier in China but they claimed their pumps don’t fail. After many tests and emails, I removed the pump from the bore and made a video of it running in a container of water. The video clearly showed that it didn’t pump water but rather blew out smoke. Only then did the manufacturer agree to replace the pump—if I paid the shipping from China for the new one.

When the replacement bore pump arrived, I installed it in the bore and wired it through the float switch (a boat bilge switch) mounted upside down in the top of the rainwater tank. This switch turns the pump off when the tank is full.

Read the full article in ReNew 131.

14-11-30 3 Batt charger inverter

Going off-grid slowly: a DIY project

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Stan Baker dreams of ditching his energy company and going off-grid. He explains how he aims to achieve this, one step at a time.

The well-documented ‘gold plating’ of the poles and wires networks has meant rising service fees for consumers despite falling demand for delivered energy. My own electricity bills reflected this and caused me to seriously consider leaving the grid altogether. A further consideration was the increasingly disruptive weather being experienced around the country resulting in power outages caused by high winds and electrical storms. When attempting to be energy independent, however, the problem is the high cost of the batteries and other equipment necessary to generate and deliver electricity.


Being something of a DIY type, I considered what bits I had sitting around in my garage and what expertise I might have that could be relevant. A passion over the years for converting hybrid cars to plug-in hybrids meant I had a reasonable understanding of lithium batteries, including the management electronics needed to ensure their longevity. I also had a 1.5 kW, 12 VDC Latronics inverter acquired years earlier for some long-forgotten project. Naturally, I had the usual nerdy stuff such as miscellaneous electronic parts as well as some understanding of microcontrollers.

In effect, I had much of what was needed to deliver 240 VAC off-grid, but with one question unanswered: where was the input energy to come from?

First attempts

My house has a flexible pricing plan from Origin that provides cheaper electricity between 11 pm and 7am. This meant I had a lower cost source of electricity for charging the batteries, at least for initial trialling. So, about six months ago I put together a simple system using lithium iron phosphate (LiFePO4) batteries from an electric vehicle conversion that were down to around 50% of their original capacity and therefore unsuited for vehicular use.

The battery charger was a simple linear unit that used toroidal transformers. I had my fuse box modified so that the lights in the house could be powered either from the inverter or directly from the mains.

The original system was not particularly efficient and I estimated I was losing around 50% of the incoming energy, mainly due to the battery charger. However, it did keep my lights going during most nights and encouraged me to consider a more sophisticated battery storage system.

Read the full article in ReNew 131.

IMG_4484 400px

Off-grid EV charging

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From off-grid electric vehicle (EV) charging to a desire for more sustainable transport, EV owners share the stories behind their choices with Robyn Deed.

Until recently, number one on Ross Ulman’s ‘bucket list’ was owning an EV and charging it from the sun (a ReNew kind of bucket list!). He got to tick off that item late last year after buying a secondhand Nissan Leaf, with 10,000 km on the clock, around the same time as he and his wife Vivienne moved to their new energy-efficient off-grid home near Daylesford.


He bought the Leaf from a friend who was upgrading to a larger EV, a Mitsubishi Outlander, which, with its ‘range extending’ petrol engine meant the friend could do without a second fossil-fuelled car. Pure EVs are probably uncommon in the country, says Ross, because of the longer distances travelled and the resulting ‘range anxiety’. Range doesn’t cause Ross problems, however. He plans ahead for his longest trip, about 90 km return to Ballarat for work, which is well within the 120 km range of his fully charged Leaf (the quoted range is 170 km, but he finds he only gets about 120 km with the hilly driving around Daylesford). His main driving is into and around Daylesford, about 15 km, all easily doable without mid-trip recharging.

He doesn’t drive the Leaf for his occasional trips to Melbourne, though driving there from Daylesford would be no problem, and charging in Melbourne would be no problem also, as there are charging stations in the city. However, the trip back to Daylesford would be problematic as, even if leaving Melbourne with full charge, the Leaf would need a further charge, albeit a short one, on the journey home—the increase in altitude uses more power than the downhill run into Melbourne. Ross is planning to upgrade in a couple of years, when a Leaf with double the range is slated to become available. He hopes that affordable EVs with double or triple the range of the current Leaf will make them more mainstream. And leadership from government is also needed. “EVs are the future of the car industry,” he says, “but we really need strong public policy with incentives and infrastructure investment.”

One interesting aspect of Ross’s EV is that it’s charged off-grid. He only charges the EV during the day when the sun is shining, a bit different from the usual overnight charging regime. The off-grid system, designed by Off-Grid Energy Australia, is AC-coupled, which Ross says has been fantastic, enabling him to charge the EV at the same time as the house batteries are charged: any draw from the house or car comes direct from the solar panels (when they’re producing energy), rather than from the house battery, reducing battery cycling.

The solar PV system is oversized (10.5 kW solar and 40 kWh batteries), which the system designers say should be sufficient to charge both the house batteries and the car even on cloudy days. So far (they’ve had the system since November 2014) there have been a couple of runs of four or five cloudy days and sufficient energy has indeed been generated.

Ross plans to work around his solar system production to avoid over-discharge of the batteries. If there’s a run of rainy days, he won’t charge the Leaf: if it has enough remaining charge he’ll drive it short distances; and, if it hasn’t, then he’ll make alternative transport arrangements, such as using their petrol vehicle or public transport. So what’s next for Ross’s bucket list? Well, there’s that Leaf upgrade in a couple of years. Or perhaps it’s just time to settle back and enjoy demonstrating that off-grid and EV can go together.

Read more stories about EV ownership in Best EVer stories: Electric vehicle owners share the love in ReNew 131.

Q&A: Battery and solar developments

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Q: I HAVE read and heard that the next generation solar batteries superseding lithium will be available and ready for market in two years time. That being the case, can you please indicate whether a hybrid solar system currently working on lead-acid batteries can be retrofitted with the upgrade?


Also, are you aware of any developments whereby solar panels can be wirelessly connected to the inverter/batteries i.e. the solar equivalent of wireless internet connectivity on a laptop?

Lastly, are you aware of any double-glazed, aluminium or wood-framed window systems with integrated solar panels, either already available or coming to market? Would ReNew be able to run a feature on this subject at some stage?


A: THERE IS a lot going on in battery development at the moment, but most of it is focused on modifications to lithium chemistries, such as using silicon nano-wires in the electrodes to reduce degradation and improve lifespan and energy density. There are some other chemistries around, such as the Aquion Energy sodium ion battery, as well as rechargeable zinc-air batteries, flow batteries and a few others. However, for the moment the two industry workhorses are lead-acid and lithium chemistry units, in particular lithium iron phosphate (LiFePO4) for larger storage requirements.

The cost of lithium batteries is steadily decreasing and with the commissioning of Tesla’s Gigafactory next year, the price is expected to go below US$150/kWh by 2020, possibly as low as US$100/kWh. So, for the next decade or so, lithium batteries are most likely to be the best bet. All of the other chemistries are really in their infancy as far as development is concerned.

Whether you can upgrade to a newer battery type will depend on the other system components and the proposed battery system. For example, a battery system with similar voltage range during charge/discharge will probably be able to be used, provided that the solar charge controller in the system can meet the charge requirements. Some charge controllers have fully programmable voltage setpoints, so that sort of controller is more likely to be able to handle a new battery chemistry. However, most battery chemistries in development have their own management systems, so they may not need a charge controller at all: the management system will control charge and discharge of the battery.

The other issue will be your inverter and whether it can handle a possibly wider voltage range of a new battery chemistry. Many inverters also have programmable minimum and maximum voltages, so there’s no way to know without knowing your current inverter model and the new proposed battery chemistry.

Wireless data transfer and wireless energy transfer are very different things. Data transfer only takes milliwatts of power, whereas energy transfer for a typical domestic solar power system would need to be in the kilowatts—a million times more power at least. There are prototype energy transfer systems being developed and some have reached the stage where 100 watts or more of usable power can be transmitted over a short distance (inside the same room, for example), but these have relatively low efficiency compared to running cables, as well as much greater cost and complexity. They also require the room to be filled with an alternating magnetic field of considerable strength—something that many people might find disconcerting. So far, all domestic-scale wireless energy transfer devices have been aimed at the gadget market—charging mobile phones and the like.

Regarding solar windows, there have been a number of companies working on these, and we have covered some installations in the past, such as in ReNew 101 where we looked at windows at Ballarat University, Schott Solar’s ASI transparent thin-film panels. However, it appears they no longer make them. Most of the manufacturers that were using their glass modules also seem to have disappeared, except one, although they don’t appear to be using the Schott modules:

Kaneka still make transparent PVs, but in the last PV buyers guide (ReNew 126, just over a year ago), we found no transparent PVs available here.
There are several companies working on new transparent glazing materials, including Oxford Photovoltaics (, New Energy Technologies ( and SOLPROCEL (

When interesting products hit the market we always try to include them in the Products section, so that’s the best place to keep an eye out for them.

—Lance Turner

To read more questions and answers, buy ReNew 131.


Product profile: Heat exchange SHW systems

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Because the potable water is stored directly in the main tank, most solar hot water systems have to be regularly boosted to high temperatures to eliminate any possible legionella threat. This wastes energy and can mean that, in cooler climes, you have a solar-boosted electric system rather than electric-boosted solar.


Red Circle Solar’s range of evacuated tube solar water heaters use open-vented (unpressurised) storage tanks with a copper heat exchange coil inside. This enables mains-pressure potable water to be heated as it passes through the heat exchange coil without any possibility of legionella contamination, eliminating the need for regular boosting.

The systems come with 200 or 250 litre stainless steel tanks and 24 or 30 evacuated tubes respectively. Being close-coupled systems, they work on thermosiphon, so there are no pumps required, simplifying the system and reducing costs and maintenance.

The systems can be connected to a wood heater for backup, but also have a 2.4 kW electric booster element should it be needed. Warranties are 10 years on tank, manifold, evacuated tubes and frame and two years on all electronic components and float valves.

RRP: $1749 for the 200 litre model, $1999 for the 250 litre unit, plus delivery. For more information, contact Red Circle Solar, Victoria,,

For more product profiles, buy ReNew 131.