Editorial ReNew 125
We don’t often get the chance to feature a garden on the cover of ReNew. On the roof of a heritage terrace in Melbourne sits this haven of biodiversity, which also acts as a temperature moderator for the home below. With a 10 °C drop in summer temperatures in the roof space and a sprinkling of Australian native flowers to behold, this is sustainable technology meets botanic beauty.READ MORE »
The accompanying article argues for the many advantages of green roofs, with an added plea to think beyond the introduced succulents commonly used. Brod Street has found plants he recommends for both beauty and bees—and, luckily, he’s prepared to share them with us!
The wider question we tackle this issue is water saving. We felt strongly it was time to put the spotlight back on water, especially given the changing weather and rainfall patterns around Australia.
As part of our water saving focus, we tour a 10 Star home where the garden and water saving features are an integral part of that design, making it what we call 10 Star inside and out. Interestingly, the design is ‘open-source’ with plans, videos and more info available online. It’s also affordable, with a deceptively simple design to show that you can do 10 Star on a budget. It’s the brainchild of ABC Gardening Australia’s Josh Byrne and is part of his mission to push sustainable building into the mainstream.
Our buyers guide this issue fits the theme too—it’s on rainwater tanks, with a clear breakdown of tank types and a discussion of the sustainability of each.
One of the big water users in a household can be the toilet, so we ask the question: how low can you flow? We present a range of low water-use toilets and even get a quick guide to a DIY composting toilet. We also provide a reminder of the big and little things you can do to save water around the home, apart from ‘befriending a bucket or two’ (my dad’s chosen water saving technology!)
We’ve also got a couple of other home projects this issue, one with a high-tech water recycling system that’s made a Sydney home 96% self-sufficient in water, and one using greywater for food production. And we look at alternative technology for housing estates—a communal stormwater harvesting system to provide water cleanup, a water resource and public parkland.
Plus: Richard Keech argues it’s time to switch our thinking away from gas as a sustainable energy source, we round up the Australian entries in the World Solar Challenge, Rhys Freeman takes us through the thinking behind an EV van conversion, and we follow a DIY project using a Netduino microcontroller to monitor a solar hot water system. All our regulars are in too, of course. We hope you enjoy the water saving theme and the many other articles—let us know!
One of the most disappointing aspects of this year’s federal election campaign (result unknown as we go to print) has been how climate change and the environment in general have slipped off the political radar. It is a long way from the 2007 federal election that had climate change front and centre, along with policies to take action. Climate change and the environment instead are only talked about in the negative.
This is despite the ABC Vote Compass showing that the majority of voters believe the federal government should be doing more to tackle climate change. This was across party lines with over 42% of Coalition supporters wanting the government to do more about climate change, even though many oppose a carbon price/tax.
It is timely that ReNew is focusing on water saving this issue, as this too seems to have gone out of fashion. With the end of the drought across large parts of Australia, the incentive for households to reduce their water use or to capture and reuse our water resources has similarly ended. It is sad to think that the only time environmental issues rate highly is when we are suffering from extreme weather conditions such as drought, fires or floods, events that are only going to become more frequent with increases in climate temperature.
Whichever party has won it looks like it will be up to the community once more to take the leadership role in pushing for action on climate change—something ReNew readers will be at the forefront of.
Rooftop diversity – Beneficial uses of rooftops
From farming to education to biodiversity, Brod Street considers the many and varied uses of rooftops.READ MORE »
In the past, building practices embraced the use of rooftops for all sorts of beneficial uses—for food production, aesthetics, education and recreation.
The capital of rooftop variety must be New York where flat roofs once supported libraries, school sports, a school for the visually impaired, playgrounds and roof gardens. Today New York embraces green roofs as a cost-effective way to deal with a host of urban problems. For example, they help manage peak stormwater flows into the city’s only sewer, which has to cope with both stormwater and wastewater. Reducing the volume of stormwater helps avoid the discharge of sewage into rivers and oceans (resulting in beach closures) when the sewer can’t cope.
London has had a variety of roof uses, too. In 1921, a Mr Thomson used the Institute of Engineers roof, near Big Ben, for a farm of 200 rabbits and 36 chickens (60 eggs per week!), with the birds allowed to roam about the roof garden during less windy days.
In 1941, The Argus reported that Collins House in Melbourne possessed a large lawn on its roof, used for sitting on and eating lunch, or playing golf: “Collins House can provide rather a big surprise. On the roof is a well-kept lawn which is just a shade smaller than a tennis court. It has been there since the building originated with a group of enthusiastic golfers decided that their lunch hour could be well spent in the city if they could find somewhere to practise putting.”
Green roofs today
Nowadays in urban Australia, most green roofs contain a low diversity of plants, usually introduced succulents and sedums. They are typically installed on a flat roof with between 100 and 150 mm of planting substrate over a drainage layer and a waterproof membrane, with the planting substrate consisting of 80% mineral and 20% organic mix.
It is not advisable to use general garden soil for green roofs as it is too heavy and too rich in nutrients. Most mineral mixes are a blend to achieve the desired outcomes. Scoria mixes often contain some crushed tiles, brick rubble and coarse sand in addition to the lightweight volcanic rock. Other mineral mixes might use waste ash from power stations for its water-holding capacity. Expanded clay is another good mineral product, formed by subjecting ‘popping’ clay particles to 1100 °C to create lightweight particles up to 10 times their original diameter.
The key reason for only using 20% organic content is due to the risk of oxidation of the organic content over time, which could result in massive shrinkage of the growing medium and increased maintenance.
Possible organic mixes include coconut fibre (coir), pine mulch and rice hulls. Coir is an excellent green roof organic material given its ease of wetting, as shown by Moss Cowcher’s research (see box). It also doesn’t collapse when dry and won’t become hydrophobic (repel water), which can be a problem with some types of pine mulch. Tests by horticultural consultant Dr Geoff Cresswell also show coir is biologically active and supports a diverse population of micro-organisms.
Read the full article in ReNew 125
Josh’s house and garden
Behind 10 Star Josh’s House is a productive, water smart and shade-giving garden—and you can find the plans online, writes Jacinta Cleary.READ MORE »
As a keen gardener in a dry spot like Perth, water has always been important to ABC’s Gardening Australia presenter Josh Byrne. “From my late teens on we’ve always had water saving measures in place, and as a food gardener I’m always trying to come up with better watering systems.” There was no doubt then that ‘Josh’s House’ would be a water smart home.
Josh’s House is the name of his ambitious building project in the Fremantle suburb of Hilton. Josh, an environmental scientist, runs a landscape and environmental design business while juggling a media career and a young family. As if not busy enough, he embarked on a “long-held dream” to build his own environmentally sustainable home and documented every step via the open-source Josh’s House website, full of house and landscaping plans, fact sheets and videos to inspire anyone to build an energy and water saving home.
The two dwellings have been built in just six and a half months, with construction finishing in May. The project comprises two 10 Star homes on an 1160 m2 block, with one for his family and another for his sister-in-law. As tends to be Josh’s way, there have been no delays creating a common productive garden around the homes, with an impressive water harvesting and recycling set up.
“All in all we will use less than a third of the typical Perth water scheme consumption while maintaining a beautiful and productive shady garden,” says Josh. To do this, he’s designed an integrated water system around what he calls his “water priorities”, with rainwater capture and use at the top of his list, followed by greywater and bore water. One water source feeds into another helping to keep as much water as possible for reuse or infiltration within the property.
Rainwater tanks and beyond
With rainwater collection a priority, an efficient rainwater system has been installed. Each home has a wet system rainwater tank, where the collection pipes run underground to connect multiple downpipes from different gutters. This makes the most of the 200m² roof space available on each home. An underground diversion valve is fitted so that water that sits in the pipes for too long, possibly becoming stagnant, can be flushed into an underground soakwell to seep into the surrounding soil.
Josh estimates mains water backup will be needed just a few months of the year. His house has a 20,000 litre poly rainwater tank and the other has a 12,000 litre tank, both plumbed to all areas inside and some parts of the garden. The first rain of the season that might contain roof debris and dirt is also flushed into the soakwell, and drinking, cooking and bathing water is filtered through sediment and carbon filters.
The rainwater plan goes beyond just tanks. “You’ve got to think of the whole property as a catchment to make the most of rainwater. It doesn’t have to all go into a tank, you can include swales and rain gardens,” says Josh. Along similar lines to the soakwell, rainwater from the carport and front verandah downpipes goes into a native damp land soak feature, similar to a drain wrapped in geotextile fabric. This water infiltrates the soil and helps to recharge the groundwater, while creating a zone for water loving plants such as native rushes and sedges.
Read the full article in ReNew 125
A rainwater tank buyers guide
A rainwater tank is one of the best ways to become more water self-sufficient, but which tank is right for your home? Lance Turner looks at the options.READ MORE »
Rainwater tanks come in almost any size, shape and colour you can imagine, with a variety of materials to suit different preferences or usage requirements. So what should you look for when buying a tank?
The first decision you have to make is where the tank will be located. Where you place the tank will determine its size and shape, and possibly even its colour if it needs to blend into the surrounding vegetation or dwelling walls. A large yard offers a number of options. You could place it next to the house or shed, or even under the house.
You also need to consider how the water will get from the roof into the tank, as well as overflow piping. However, there are a number of different systems for plumbing a tank to a home’s gutters that allow a tank to be situated some distance from the home, so this should probably not be an overriding consideration.
The six most common rainwater tank materials are concrete, fibreglass, plastic (usually polyethylene, often just called ‘poly’, or PVC, used in flexible bladder tanks), Aquaplate Colorbond (thin sheet steel with a colour coating on the outside and a waterproof coating on the inside), galvanised steel and stainless steel. Each of these materials has advantages and disadvantages, so let’s look at a few of those.
A water tank can be a considerable expense, even after a rebate, so you want it to last as long as possible. The expected lifetime of any tank should be at least 20 years, and indeed, many tanks come with a 20 or even 25 year warranty. However, a number of factors will determine just how long the tank actually lasts, and that includes water quality, maintenance and positioning of the tank.
For example, plastic tanks are relatively immune to damage from salty water, so if your tank is regularly topped up from a bore or dam, then a plastic tank might be the best solution. However, if your tank only needs to hold rainwater, then any tank material should be suitable.
The tank’s location can affect the lifetime of the materials. Ideally, the tank should be located in shade if possible, not just to keep the water temperature low and reduce evaporation, but also because some materials are degraded more rapidly by direct sunlight.
Most poly tanks will slowly degrade over time with exposure to the sun, despite having UV inhibitors added to the plastic. Because the plastic is being used to hold water, there are limits to how much UV inhibitor and other chemicals can be added to the polyethylene, so eventually the tanks will suffer some degradation.
Metal tanks come in three common materials. Corrugated galvanised steel tanks have been popular in both rural and urban situations for a long time.
Another steel tank type, Aquaplate, is a derivative of Colorbond steel. It has the colour coating on one side and a waterproof coating designed specifically for tank manufacture on the other. Provided the coating is not damaged during the tank manufacturing process and seams are correctly formed and sealed, the tank should last a great many years.
Stainless steel tanks are known for their durability and strength. They are generally small modular tanks for urban use, but large stainless steel tanks are also available. These are made from corrugated stainless steel that looks much like corrugated iron, just a lot shinier. While stainless steel tanks can be more expensive than other types, they have a number of advantages which we will look at later.
Concrete tanks can be quite durable, but they do tend to sweat if they don’t have a plastic or rubber liner. If you look at a concrete tank that has been around for a while, it is not uncommon to see white powdery ‘salt’ residue on the outside.
Read the full article in ReNew 125
The sunny side of the street – Solar cars evolve
Amy Rolfe checks out the cars competing in the 2013 World Solar Challenge, powered by nothing but solar energy.READ MORE »
The battle for efficiency and sustainability can be seen in everything from recycling bins to our rooftops as Australian society becomes more concerned about the damage our way of life is having on the environment. One sector of our lives, however, has remained relatively untouched—our cars. The electric car movement has begun to work on this problem as they integrate with rooftop solar systems and upgrade petrol vehicles with electric motors and increasingly light lithium battery packs. But another group of enthusiasts has taken a different approach.
The World Solar Challenge (WSC) has been running since 1987—a marathon 3000 km journey from Darwin to Adelaide powered by nothing but solar energy. Teams leave Darwin and drive as far as possible until 5 pm each day, when they must stop wherever they are and set up camp until the next day. In 2013, 48 teams from 24 countries are participating in the WSC.
The vehicles fall into three different classes—the Michelin Cruiser class, the Go Pro Adventure class and the indubitably gorgeous Challenger class.
The Cruiser class is created for practicality—cars that would meet road registration requirements in their country of origin and carry the driver and at least one passenger.
The Adventure class consists only of cars that have already participated in previous races, including the WSC.
The Challenger class is at the forefront of design, striving to create faster, sleeker and more energy efficient cars than any that have ever graced the Stuart Highway. This year, 28 teams have cars in the Challenger class. Two of these teams are Australian: TeamArrow, a Queensland-based team, who are participating for their first year ever with the Arrow1, and the University of Western Sydney, with their vehicle the SolAce.
Two other Australian teams, the TAFE SA Solar Spirit team with Solar Spirit 3 and UNSW Sunswift with eVe, are partaking in the Cruiser class, and the Aurora Vehicle Association are participating in the Adventure class with their familiar car, the Aurora Evolution.
A guide to form
The Aurora team manager, Andris Sampsons, gave us an insider’s opinion on the likely top contenders this year: “The Challenger class represents the pinnacle of solar vehicle efficiency. Based on previous form and their new vehicles it looks like the top picks would be Nuon Solar Team, Nuna 7 (Netherlands), Tokai University, Tokai Challenger (Japan) and University of Michigan, Generation (USA).”
But he notes: “In pushing the envelope on efficiency and performance, some teams are pushing the design rule boundaries and it will be interesting to see whether the prizewinner will be ultimately determined by post-race protest, rather than on the line placing.” Interesting!
In the revolutionary Cruiser class, Andris likes the look of both UNSW Solar Racing Team’s eVe and the Hochschule Bochum Solarcar Team’s PowerCore SunCruiser.
Read the full article in ReNew 125
Know your renewables – Solar hot water system basics
Solar hot water systems are steadily becoming more popular in Australia. Lance Turner explains the types and how they work.READ MORE »
Solar water heaters have been around in their modern form for almost 100 years. However, there is a lot of confusion between solar water heaters and solar photovoltaics, the common ‘solar panels’ that generate electricity directly.
Solar hot water (SHW) systems are what’s known as a solar thermal technology. They use the sun’s heat to heat water, either directly or indirectly. There is generally no electricity involved, except for the use of circulation pumps and backup boosting in some systems.
The basic design is that a flat panel that contains tubes for the water to flow through is connected to a storage tank. Water flows from the tank, is heated in the panel by the heat of the sun and flows back to the tank as heated water. However, there are a number of different configurations of tank and panels, and each has a different method of getting the water to the panels and back to the tank.
The simplest type is the close-coupled direct heating system. In this, the solar collector is mounted on the house roof with the water tank mounted directly above it. Water flows from the tank into the collector where it is heated by the sun. As warm water is less dense than cold water, the warm water rises up through the collector tubes and flows back to the tank as heated water, drawing colder water from the tank into the bottom of the collector for heating. This system is called thermosiphoning and is the most reliable and simple of the solar thermal water heating systems.
The other common system usually has the tank mounted at ground level, either inside or outside the house. A pump circulates water from the tank up to the collector, where it is heated and then flows back to the tank. A pump is needed in such systems as thermosiphoning only works when the tank is mounted above the panels. The pump is controlled by a special controller that has multiple temperature sensors in the tank and the collector.
This type of system is known as a remote-coupled or split system. It is more complex than a close-coupled system due to the added complexity of the pump and controller.
While there are two main types of systems, there are also two main types of solar collectors. The first is the flat-plate collector, which is a flat, insulated box containing an array of pipes connected to a metal sheet, all painted black. The metal sheet absorbs incoming solar heat and transfers it to the attached pipes and hence the water inside them.
Read the full article in ReNew 125
Flushed with pride – Water saving toilets
Beth Askham takes us on a tour of some water saving loos.READ MORE »
Toilets can flush away litre upon litre of potable water, with up to 25% of our home’s water going down the toilet.* It used to be worse; before 1982 when dual-flush toilets were introduced, toilets in Australia had an average flush volume of 11 litres. Now, the most efficient toilets use around 3.3 L per flush and to use less water than this we might need to radically change toilet design. New water-saving toilet designs in the pipeline incorporate air assistance, vacuum piping or urine separation.
How low can we flow?
Dual flushing is the standard for water-efficient toilets in Australia. The most efficient dual-flush toilets use 4.5 L for a full flush and 3 L for a half flush, with an average flush volume of 3.3 L. These toilets are rated as 4 stars under the WELS rating scheme (the more stars, the more efficient the model). Some models with an integrated hand basin that flush with greywater reach 5 stars, but there are no 6 star toilets available at this stage.
Indeed, we may be at the limit of the minimum amount of water used for flushing. Too little water in a flush can create drainage problems as it’s the water that pushes the waste along sewer drainage lines. Ways to get around drainage issues and still reduce the amount of potable water used includes flushing with greywater, using a Drainwave that releases water from your house in stored batches (see www.drainwave.com.au) or using another type of toilet that doesn’t depend on water–such as those that use air pressure to flush or composting toilets.
Urine separation toilets
Urine separation toilets reduce the amount of flushing required. They are more common in Europe but there are some examples of their use in Australia. The University of Technology Sydney (UTS) Institute for Sustainable Futures is working to divert urine from their sewerage system by installing dual plumbing at its Barangaroo development and in their new UTS Broadway building in Sydney. They plan to reuse the urine’s nutrients as agricultural fertiliser. “It could easily be argued that ‘taking a leak’ is our most apt description for going to the toilet as it literally involves leaking valuable resources into the waste stream,” says Professor Cynthia Mitchell, who is leading the project.
Vacuum toilets are increasingly being used in offices, public buildings and portable toilets, but it’s still early days for them in residential dwellings. Vacuum toilets use less than one litre each flush and it’s only to wash the pan. They essentially use atmospheric pressure to push waste into toilet piping that’s kept at a lower pressure.
Pumps keep the piping network at a 55% vacuum and when a toilet is flushed, this drops to 35% before it builds back up. All waste is macerated and then sent to the sewer, avoiding any drainage issues. An advantage of vacuum toilets is that you can place them anywhere in the building layout without needing to account for gravity-fed piping, as the vacuum piping can remove waste vertically if needed. Managing Director John Neskudla of Vacuum Toilets Australia says, “Vacuum toilets are the future; we cannot continue to flush our most precious resource down the toilet.”
Read the full article in ReNew 125
Monitoring a rooftop solar hot water system
David Gobbett used a Netduino microcontroller to monitor the temperature fluctuations in his rooftop solar hot water system. He describes the setup and what he’s learnt.READ MORE »
For decades, the first or only solar appliance installed by many Australian households was a rooftop solar hot water system. My parents installed one on our family home in Adelaide in the mid 1970s. In my current home we installed a conventional 300-litre rooftop system in 2006. Superficially at least, the design seemed to have changed little over the intervening years. In both cases an electric booster was connected to off-peak power, which is switched on automatically by the power meter from midnight to 7 am each day.
To reduce our energy consumption over summer, we turn off the electric booster at the main switch during late November to late March, and we still have adequate hot water most of the time. However, occasionally we unexpectedly get caught short of hot water, and at those times it’s been frustrating having no way of knowing how hot the water in the tank actually is.
Another concern with switching off the booster is that there are potential health issues when hot water system temperatures are allowed to drop below 60 °C. Lévesque et al. (2004) indicate that Legionella bacteria can grow in water temperatures up to 45 °C, but that growth stops above 55 °C, and over 60 °C the bacteria are killed. Even in hot water systems with the thermostat set to 60 °C, the lower part of the tank can remain at temperatures that are optimal for Legionella growth. It would be nice to avoid this—but that would entail having a way to sense the temperatures in the tank, which is high up on the house roof.
A project idea was sparked when a friend showed me that he was using a small microprocessor board to log solar PV power outputs. He had also connected a sensor on his water meter so he could log household water consumption. This inspired me to start on my own project to get a better understanding of what the temperatures in my solar hot water system were doing.
My interests in this project were to:
• minimise unnecessary power usage
• know when we’re running low on solar hot water, so the booster can be turned on
• minimise any risk associated with Legionella.
Setting up the temperature logging
Although I have experience as a computer programmer, I had never programmed microprocessors or worked with such things as temperature sensors. After some internet research I decided to use 1-wire devices (1-wire is a technology by which sensors and other devices can communicate). I took the plunge and purchased:
• 1-wire temperature sensors (DS18S20; 10 of these cost $18). These sensors operate over a temperature range of -55 °C to +125 °C. Several of these sensors can be connected to a single cable to form a mini network where each sensor has its own unique identification.
• a USB to 1-wire adaptor, to allow me to connect the sensors to my PC for testing (DS9490R; $28)
• a Netduino Plus microcontroller (US$70) which included a network socket and micro SD memory card slot. (See side box ‘Arduino style microcontroller boards’).
I proceeded to build the system in small steps. First I soldered three of the 1-wire sensors to a length of old telephone extension cable and then used the 1-wire to USB adaptor to connect them to my PC. Using free software (from www.maximintegrated.com) I was reassured that I had wired them correctly (phew!). Then with some extra lengths of phone extension leads, I inserted the sensors under the insulation at one end of my hot water tank and immediately saw big differences between the top, middle and bottom of the tank, as well as temperature changes in response to hot water use in the house. This was encouraging since it showed that I could get useful temperature readings from the outside of the tank.
Read the full article in ReNew 125
ReNew reader competition
Are you on the move and living sustainably?READ MORE »
We want to know how ReNew readers save energy and live sustainably when caravanning, camping or holidaying.
Send a picture and a description up to 100 words to firstname.lastname@example.org with the subject line ReNew reader prize by 15 November.
You could win a 120W folding solar panel kit from Low Energy Developments and we will also publish your story in ReNew!
See the prize specifications at www.lowenergydevelopments.com.au
The Pears Report: Poles and wires welfare
The Productivity Commission fights against protection in all other industries—why not in electricity? asks Alan Pears.READ MORE »
The 2012 Senate inquiry into electricity costs delivered a damning report on the performance of energy policy makers and regulators (see my column in ReNew 123).
Now the Productivity Commission has issued its own 820-page report. It is even more scathing.
Just about every criticism made in submissions to the Senate inquiry has been supported.
“These flaws require a fundamental nationally and consumer-focused package of reforms that removes the interlinked regulatory barriers to the efficiency of electricity networks. Reforms made in late 2012, including improvements to the regulatory rules, better resourcing of the regulator and greater representation of consumers, have only partly addressed these flaws.”
“Delays to reform cost consumers across the National Electricity Market (NEM) hundreds of millions of dollars.”
“There is, in effect, no point in simply fixing a punctured tyre if the car has no engine.”
I couldn’t have said it better myself…
It seems to me that the commission had to take a strong stand.
There is such widespread agreement that the energy market is a mess that to make apologies would be to undermine the future of the Productivity Commission’s broader agenda of competition and privatisation. To their credit, they have made strong recommendations with delivery dates.
Yet electricity industry welfare remains
Underlying the commission’s thinking, there is still a deep tension between open and fair markets and an assumption that the incumbent industry must be protected so it can recover its costs. So new market entrants such as solar electricity must receive only the value the incumbent industry places on their input, and pricing structures must allow incumbents to maintain their viability. This is simply a welfare scheme of a type that the commission fights against in all other industries.
The gas industry is not paid according to what it saves the existing electricity industry when someone switches to or from gas cooking. Online media are not paid what they save the hard copy media. And so on.
A classic example of the ‘welfare’ approach is the commission’s conclusion that rooftop solar should, in the short term, be paid only what it saves on generation and, in the longer term, what it saves the networks. In the meantime, it proposes that retail electricity prices should be deregulated: a licence for the incumbent industry to use its market power to block emerging competitors.
The value of rooftop solar
Rooftop solar should be allowed to sell power to neighbours independent of the grid, or be paid the retail price at the time it exports, in the same way that consumers benefit at the full retail electricity price if they save electricity or switch to gas.
On the one hand, the rate paid to PV owners should be higher than the retail price, because this is ‘green electricity’ being fed into the grid, which is worth more. On the other hand, it is fair that the PV owner pays for use of the part of the network they actually use: that is, the very small part of the network used to deliver the PV-generated power to whoever uses it. However, this latter is very different from saying that they should be paid only the wholesale electricity price, or close to it, which assumes they use the whole network and transmission system and deserve no credit for reduced power-line losses.
In theory, such an arrangement should force networks and retailers to introduce cost-reflective tariffs. But they have enormous market power and will not do this unless they are very carefully supervised, and independent analysis is done to cross-check their pricing approaches.
To avoid cost impacts on the grid beyond the neighbourhood level, a network could choose to install local energy storage to absorb the excess PV output at appropriate times. This storage could also enhance network profits if used to store cheap electricity for sale into the grid at times of high prices. So the cost of storage to solve the PV problem could be offset by the potential for greater profits.
Who pays to cover fixed costs?
The argument for higher fixed charges to cover network capital costs is also flawed. As the industry itself tells us, much of the network infrastructure is old. Logically, this should mean its capital value is heavily depreciated, so fixed costs are low for much of the grid. But the buyers of networks paid inflated prices, so their fixed costs are high. Why should consumers pay this cost?
These were business decisions: shareholders, not consumers, should pay the price of poor decisions. And governments that have chosen to inflate the value of their network assets need to take responsibility for their decisions, not solve their problem by killing energy innovation and cost reduction.
The commission needs to step back and imagine what a truly competitive energy services sector might look like, and frame its policy recommendations accordingly.
Debating (again) a national scheme for energy savings
In recent years, several state-based schemes that create energy retailer obligations to deliver greenhouse gas abatement via end-use consumers have appeared. These include the NSW Energy Savings Incentive (based on the previous Greenhouse Gas Abatement Scheme), the Victorian Energy Efficiency Target (promoted as the Energy Saving Incentive) and South Australia’s REES. The Victorian and NSW schemes use trading mechanisms.
Debate about such schemes has a long history, which is worth considering as we debate the federal government’s recent report on the costs and benefits of a National Energy Savings Initiative (NESI).
In 2003, the NSW government introduced its Greenhouse Gas Abatement Scheme—the world’s first emission trading scheme. Abatement certificates could be created through a variety of actions, including energy efficiency.
In 2007, Democrat Senator Lyn Allison (a long-term advocate for energy efficiency) proposed a similar national scheme. This was considered by a Senate Inquiry. I made one of 17 submissions, and also presented evidence. It was very clear that many influential people in the Canberra bureaucracy and politics were strongly opposed to such an approach. In my evidence, I warned that if the federal government didn’t act, individual states would, and we would have to clean up the mess in the future.
The inquiry concluded that the (then) proposed Carbon Pollution Reduction Scheme would deal with this issue within a broader framework. It didn’t. So the Victorian and South Australian governments introduced schemes in 2009.
In its conclusion, the inquiry commented that “An energy efficiency scheme set up in isolation from other climate change strategies may increase the cost of securing emission reductions…“ It’s strange how energy efficiency has to ‘fit in’ while energy market policy is allowed to conflict with policy on climate change. In practice, the present carbon trading scheme doesn’t effectively address energy efficiency either.
The 2010 Prime Minister’s Energy Efficiency Task Group proposed a national scheme. But powerful econocrats argued that carbon pricing would make such a scheme unnecessary, while energy retailers, who would carry the obligation, were not excited by the idea of paying to undermine their profits from energy sales. So it was to be “investigated”, not implemented.
Three years later, we have a paper reporting on (very conservative) economic analysis that shows substantial net economic benefit from a national scheme based on the NSW and Victorian models. I wish I could get excited about this, but the reality is that this was obvious a decade (indeed, several decades) ago.
The questions remain. Will a national scheme actually be introduced against the opposition of vested interests whose business models are falling apart along with purist economic policy designers? Will a weak target be set, creating yet another ‘boom and bust’ sustainable energy market? Will the scheme be designed to deliver real savings? Will it integrate incentives for avoiding peak demand and storing energy?
Don’t hold your breath.
Alan Pears has worked on sustainable energy issues since the late 1970s. He is one of Australia’s best recognised and most highly awarded commentators on sustainable energy and climate issues. He teaches part time at RMIT University and is co-director of Sustainable Solutions, a small consultancy.
ATA Branch Report
ReNew is published by the not-for-profit ATA. The ATA has active branches all over Australia and here’s what they’ve been up to recently!READ MORE »
Adelaide: In the last few months the Adelaide branch heard from experts on the topics of cool roofs, household Energy Star ratings and had updates on hybrid cars and PV systems. They also partnered with the City of Marion to hold an ATA Speed Date a Sustainable Designer event in August.
Brisbane: In May, the Brisbane branch assisted with an ATA Speed Date a Sustainable Designer event and investigated the concept of positive development. Their June meeting was a presentation on sustainable building materials and in July they learnt about solar cooking and off-grid power.
Cairns: The Cairns branch had a huge weekend of activities in July with an ATA stall at Mareeba Markets, the Cairns Sustainable Living Expo and a talk on the advantages of hempcrete as a building material.
Geelong EV: The Geelong EV branch continued regular meetings to look at the latest in EV technology from around the globe and to discuss member projects. They also meet monthly in private workshops to assist fellow EV builders.
Melbourne: The Melbourne branch has held meetings recently on the varied topics of window and glass technologies, community renewable energy, coal seam gas and the ATA International Projects Group’s activities in East Timor.
Melbourne EV: The Melbourne EV branch has heard from industry experts on electricity network management and smart meters, investigated the exciting world of electric vehicle racing developments and held a film night with the popular documentary Revenge of the Electric Car.
Sydney Central: The Sydney Central branch has recently hosted a number of excellent speakers on topics relating to sustainable building, including ‘Why natural buildings are better’ and separate sessions on how to make insulation and glazing work for you.
Sydney West: The Sydney West branch recently visited the University of Western Sydney’s solar car ‘Solace’ workshop. This branch is based at the Hawkesbury Earthcare Centre which hosts a range of workshops and education sessions. A weekend-long workshop in August focused on unfired earth building techniques.
Tasmania North: The Tasmania North branch has been out and about again, visiting their local sustainable supermarket as well as hosting a federal election policy forum. In August a number of branch members were involved in a range of events as part of Sustainable August with Tamar NRM’s Sustainable Living Working Group.
See www.ata.org.au/branches for upcoming events, including from the ATA’s other branches in Canberra, Coffs Harbour, Perth, Sunraysia and Warkworth, New Zealand.
Product profile: Ultra low-power server
Servers are usually large, ugly computers that suck electricity like there’s no tomorrow. Reliability and processing power is usually prioritised over energy efficiency, but it doesn’t have to be that way.READ MORE »
CompuLab has a reputation for making amazing, tiny computers with very low energy consumption. They have recently expanded their range with the uSVR, a beefy little server suitable for a great many uses.
Features include a completely fanless, all-metal case measuring just 60 x 160 x 260 mm, Celeron or Intel Core-i7 processor, up to 32 GB ECC RAM, four internal 2.5” HDDs in RAID 0, 1, 5, 10 or JBOD configuration, optional mSATA drive up to 480 GB for the operating system, up to six gigabit ethernet ports and various other options. Power consumption is rated at a tiny 8 to 35 watts, depending on system configuration and load.
At time of writing we hadn’t found any retailers of this amazing little server and so it is only available from CompuLab directly. Wholesale price for 1000+ quantities start at US$ 556 and the one-off price is 20% higher, or US$ 667. An evaluation kit is also available. Note that there are minimum purchase quantity restrictions for non-standard configurations.
Product profile: Benchtops from paper
Australian-made Paperock is a high-strength building material made from multiple layers of 60% recycled or sustainably sourced paper (not certified) which can be used for benchtops. It is bonded with phenolic resin and heat, and pressure cured to form an extremely strong material.READ MORE »
It is virtually impervious to water, highly stain resistant, can be worked like hardwood and is available in a number of colours: black, sand, brown, green, a black and brown sandwich and a black and sand sandwich.
Because of its high strength, benchtops made from Paperock need not be as thick as with other materials, saving weight and cost. Paperock produces no VOC emissions and is heat resistant to 180 °C.
Paperock is made to order and is available in 3, 6, 10, 18, 25 and 32 mm thicknesses, with 50 mm on special order. Standard sheet sizes are 2.44 x 1.22 m or 2.85 x 1.35 m sheets. Maximum sheet size is 2.85 x 1.35 m.
Paperock also supply a similar US-made material, PaperStone, made from FSC-certified recycled paper and bonded with phenolic resins made from natural materials like cashew nut shells.
Q&A: Increasing system load
Since my household increased from one to three members I am finding my 1500 W renewable energy system, which was more than adequate for a frugal me, is not coping with the extra residents even though we use energy sparingly, only do washing etc on sunny days and have purchased low-energy computers and fridge.READ MORE »
Our system was only designed to take up to 2000 W of solar panels, so after I put on two new panels the system is still short on energy when we have two cloudy days in a row.
My battery charger will be getting regular use from now on, but only puts 10 A (300 W) into the batteries. I am looking for a battery charger that can deliver 30 amps and reduce the time I need to run my 3000 W generator.
Longer term, I may have to buy a second system, but can you suggest a suitable charger that is not too expensive please?
There are plenty of chargers around that will do that sort of current, and more, but the maximum current rate depends on the battery bank size. See www.baintech.com.au/chargers and www.inverter.com.au/category5_1.htm for examples, and there are a lot of other suppliers, but high-powered chargers like this are never really low cost. There are some cheap ones on eBay, but bear in mind that some are not well regulated and can overcharge the battery bank, and many are direct from China, so if they fail, there’s no real recourse.
Generally, if you are finding that your battery bank is struggling after the second day then you are cycling it way too deeply and it is too small for what you are drawing from it. The use of a charger will help but it is still adding cycles to the bank and the bank will degrade faster than it otherwise would.
Something to note regarding generators, they are usually rated in VA (volt-amps), not watts. They are not the same thing unless the load on the generator (battery charger or whatever) has a power factor of 1. Very few electronic loads do, especially battery chargers, so a genset rated at 3000 VA won’t be able to power a 3000 watt charger. Obviously, a 30 V, 30 A output is only 900 W and probably needs around 1200 W input at most, but it’s surprising how much some gensets struggle with battery chargers.
To read more questions and answers, buy ReNew 125.
Q&A: LED bulbs and radio buzz
I recently bought four LED lights to replace CFLs in the kitchen. I’m very happy with the light output and colour, but unfortunately there is one side effect—when they are turned on they make my clock radio in the bedroom buzz. What is this caused by and is there anything I can do to stop it? I would just put these globes in a spot where I don’t need to use them in the morning, except that they are the only screw fittings in the house. Another LED in the pantry has no effect.
This is a common problem: many LED bulbs produce electrical noise as they have switchmode drivers inside them to convert the power supply voltage down to whatever voltage and current is needed for the LEDs. The electrical noise can be radiated as radio waves from the house wiring, causing interference, or it can travel back through the wiring as electrical noise, causing the same problem. I suspect your problem is the former.
There are a number of solutions, of which several are quite simple. The first is to get some clip-on ferrite beads, these are the sort of thing you see at the end of some computer leads, basically a lump in the cable, but in clip-on form rather than moulded in. Examples can be seen at www.bit.ly/ferrite1 and www.bit.ly/ferrite2. You simply clip them over the cable as close to the light fitting as possible.
If that doesn’t fix it entirely, using a larger ferrite and winding two or three turns of the cable through it will increase the effectiveness of the ferrite.
You can also put small value capacitors directly across the socket, but this involves electrical wiring, so you’ll need to find an electrician experienced at mains wiring, and you must also use the correct capacitors (X2 types of appropriate voltage rating). A simpler and more electrician friendly option would be to have mains filters connected at the fittings. A typical example of a suitable unit (which could be fitted inside a junction box) is Jaycar Electronics part number MS4001.
But definitely start with the clip-on ferrites, they are simple to install and no electrician needed, assuming the wiring is accessible from inside the ceiling. Just be careful if installing them that you ensure the wiring is in good condition – old wiring can have degraded insulation and be very dangerous. If in doubt, contact an electrician.
To read more questions and answers, buy ReNew 125.