Michael Green

Writer and producer

Solar energy bulk purchase schemes

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Green-minded councils and community groups can save you time, money and energy.

IN LATE 2006, at a meeting held by Ballarat Renewable Energy and Zero Emissions (BREAZE), Nick Lanyon asked how many of the crowd had solar hot water systems. “I assumed that half the room would put their hands up,” he says. “But out of 170 people there were only six hands.”

It was a green-minded audience, so Mr Lanyon asked why they hadn’t switched systems. People answered that they didn’t know which suppliers to trust, were too busy to research, and didn’t want to make the wrong decision. “So they just stayed in a situation of paralysis,” he says.

If you’re choosing solar hot water units or photovoltaic panels, it’s easy to be overwhelmed. But never fear: many councils and community groups can help you pick the right product at a good price.

Mr Lanyon and the BREAZE volunteers set about finding a good system and a supplier that would offer its members a hefty discount. The organisation also investigated solar photovoltaic panels and, eventually, became a supplier itself. “The research was fairly intensive,” he says. “We contacted nearly every photovoltaic supplier in Australia at the time.”

Altogether, he estimates that BREAZE has coordinated the installation of nearly 600 solar electricity and hot water systems. In recent years, the renewables market has surged, with big suppliers often selling cheap, low-quality systems with questionable warranty provisions. “We’re concerned about the longevity of what’s available now,” Mr Lanyon says. “People respect our independence because we exist to reduce emissions, regardless of who supplies the technology.”

Many other sustainability groups and councils have run bulk-purchasing schemes for solar hot water and electricity, so it’s worthwhile seeking information in your local area.

For residents in Melbourne’s north and north-east, Zero Carbon Moreland and the Manningham and Nillumbik councils are now offering solar hot water deals – visit their websites for more information.

Environmental consultant Bill Pemberton, from Scarab Solutions, has worked for a number of councils on similar programs. “They make it easier for people to invest in renewable energy,” he says. “A lot of the administration is done for you – the council looks at the technology and the rebates, and gets quotes from the whole industry.”

That pre-planning is particularly helpful for hot water units. “When your existing system breaks down, you need it replaced straight away,” Mr Pemberton says. “But if you want solar, you hit a wall of complexity.” For energy efficiency, he argues, it’s far better to buy a new system before your old one dies, especially if you have an electric service.

The other benefit is monetary. “By purchasing on a large scale, people can save hundreds of dollars each. In Manningham and Nillumbik we found a saving of about $300, compared to buying and installing individually,” he says.

Zero Carbon Moreland estimates that its program will cut the cost of installing a climate-friendly hot water system by $800 to $1200. Householders can also save up to 15 per cent on ongoing energy bills and up to four tonnes of carbon dioxide per year, depending on their existing unit.

With rebates constantly changing, Mr Pemberton says it pays to be on the lookout for new bulk-purchasing schemes. “I think they’ll also include appliances, such as front-loading washing machines, or even the replacement of halogen downlights.”

Embodied energy and life cycle assessment

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Comparing the impact of building products is not as straightforward as you might think.

WHEN you plan a green building or renovation, sooner or later you’ll rub up against embodied energy. The encounter is more likely to be perplexing than pleasurable.

“Basically, embodied energy is the energy it takes make a product,” says Dr Usha Iyer-Raniga, assistant director of RMIT’s Centre for Design. That can include the mining, processing and transport of base materials, as well as energy for manufacturing, packaging and delivery.

“It’s a very technical area,” she says. It’s also very imprecise. According to the sustainable design guide Your Home, findings can vary by a factor of ten depending on the research method.

Generally, the more highly processed a material, the higher its embodied energy. But it’s not as simple as opting for timber over brick, or brick over steel. Best practice manufacturing techniques can reverse the order.

Likewise, recycled content or future reuse can drastically change a material’s footprint. Also, products with higher embodied energy can shrink ongoing energy consumption, if wisely deployed. A well-placed, exposed concrete slab can cut home heating and cooling needs.

Dr Iyer-Raniga suggests householders ask a lot of questions. “People have to be really savvy. There’s a lot of greenwash out there, particularly in the building industry – not just with materials, but with appliances and furniture as well,” she says.

“You need to think about your needs. Is it a house you want to live in for the rest of your life? Think about using long-lasting materials that aren’t entirely dictated by fashion. Consider where the materials come from, how durable they are and whether they need maintenance.”

Embodied energy typically comprises about one-tenth of the energy used by a building during its lifetime. “Building codes are becoming more stringent and appliances more energy efficient,” Dr Iyer-Raniga notes. “From a whole-of-life energy perspective, embodied energy will become more significant.”

But it only tells part of the story. For the rest, you need life cycle assessment, embodied energy’s younger and more comprehensive cousin.

“Life cycle assessment looks at the cradle-to-grave impacts of a product or service, including all the relevant environmental indicators,” says Tim Grant from consultancy Life Cycle Strategies. “That might be the loss of species, the production of greenhouse gases and pollutants, or the use of non-renewable resources.”

To date, not much life cycle information is available for homeowners, although eco-product database EcoSpecifier recently introduced the GreenTag accreditation system.

Mr Grant says there are simple rules of thumb for householders to follow. “Firstly, anything that will improve operational efficiency is worth doing, whether it’s solar panels or light sensors that switch lights off automatically. The environmental impacts of production will nearly always be outweighed by savings during the life of the home.

“The second thing is to reduce the size of everything. Smaller buildings use less material, less energy for heating and have less room for furniture and fittings.”

That means modification or refurbishment is preferable to building from scratch, if it can ensure energy efficiency. Earth building techniques such as mudbrick have very little embodied energy, but to remain ahead of the rest, they must also operate efficiently.

“There’s nothing that has no environmental impact,” Mr Grant says. “After doing life cycle assessment, you come to realise that less is more. We really need to reduce our consumption of everything.”

Working in the window, on the shutters

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I have been working with Michael Kelly less frequently lately and the finer details have taken longer. But we are nearly there. The courtyard studio is nearly complete. All that remains is its assembly.

As we finished the larger panels and began the smaller ones, we moved from the rear courtyard to the front of his shop, by the tall windows. Michael’s small workshop is set up in one window, with his bench, tools, coffee machine, stereo and books. Everything he needs for a day’s work.

The studio will have two entries and we are crafting them as saloon style shutter-doors. My role, for much of the project, has been to measure and saw the hundreds of strips of Oregon lath. When I began, my routine was without routine. The sawing bench was at right angles to the table where the uncut lath waited. I would swivel left to de-nail a length, return to the table to measure, then turn left again to saw.

Soon, I shifted the sawing bench in front of me – it fitted neatly underneath the table – so I didn’t need to turn at all. I began to de-nail in batches, measure in batches, saw in batches. I placed the pen, saw and hammer conveniently at hand. Honing this simple order was very satisfying.

Likewise, the simple pattern of our shutter-doors is very pleasing. The horizontal strips of lath are fortified by a rectangle frame and x-marks-the-spot crosspieces.

I recently borrowed the books of architect Christopher Alexander. In the 1970s, he wrote a trilogy outlining his design concepts: The Timeless Way of Building; A Pattern Language; and The Oregon Experiment.

I have only read a third of The Timeless Way, but our elegant shutter-doors seem open in concert with his argument. There is something whole about their design. Alexander writes that certain patterns of materials and behaviour bring life to buildings and their inhabitants:

“…the Alhambra, some tiny gothic church, an old New England house, an Alpine village, an ancient Zen temple, a seat by a mountain stream, a courtyard filled with blue and yellow tiles among the earth. What is it they have in common? They are beautiful, ordered, harmonious—yes, all these things. But especially, and what strikes to the heart, they live.”

On those days when we work in the window of the shop, it feels like we’re getting close to the timeless way. We toil there in the daylight, listening to Bob Dylan, waving and smiling to people who passed.

“Some kinds of physical and social circumstances help a person come to life. Others make it very difficult.

For instance, in some towns, the pattern of relationships between workplaces and families helps us to come to life. Workshops mix with houses, children run around the places where the work is going on, the members of the family help in the work, the family may possibly eat lunch together, or eat lunch together with the people who are working there.

The fact that family and play are part of one continuous stream helps nourish everyone.”

My experience matches Alexander’s words. Some towns, cities, neighbourhoods and homes can make my spirit sing, and so can certain patterns in my daily life. Days and months pass as I slowly take this in, notice what works for me, and what doesn’t, and seek that which fits. 


Lower-carbon concrete

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Concrete is ubiquitous. According to Dr Peter Duxson, chief operating officer of eco-concrete company Zeobond, it’s the second most used commodity in the world, behind only water. “Everywhere there is human activity, there is concrete being used. It’s versatile and cheap,” he says. “It just turns out that the base ingredient that makes concrete go hard is bad for the environment.”

Concrete is made up of sand, rock and water, bound together with cement. Conventional concrete uses Portland cement and although it comprises only 10 to 15 per cent of the total product, it accounts for about 70 per cent of its carbon footprint.

The high emissions come from burning limestone to create lime – from both the energy required to heat the kilns and the chemical reaction in which limestone releases carbon dioxide. “One kilo of CO2 is emitted per kilo of cement,” Duxson says. “So every concrete truck equals about two tonnes of CO2 in cement.”

The material’s saving grace is its usefulness as thermal mass in appropriate solar passive design – it can help to even out day and night time temperatures. According to Riccardo Zen, from Zen Architects in Melbourne, carefully placed high-density materials are essential to cut the energy needs of homes in temperate and cool climates. “It’s very hard to eliminate heating and cooling unless you have some form of thermal mass,” he says.

An exposed concrete slab floor is a classic example of thermal mass. Positioned in front of windows in a north-facing living room, the slab receives direct sun in winter. It absorbs the solar radiation and warms the house into the night. With appropriate shading, the sun won’t hit the concrete over summer, so the chill of the concrete will help the home stay cool.

Even so, given that concrete accounts for about five per cent of global carbon dioxide emissions, the race is on make lower-carbon concrete.

The simplest way to do so is to substitute a proportion of the Portland cement for other products. Fly ash and slag (by-products of burning coal and smelting iron ore, respectively) can comfortably replace over one-fifth of the cement content without adversely affecting the quality of the product.

Boral’s Envirocrete is available with either 30 or 60 per cent less Portland cement – the difference made up with fly ash, slag and chemical admixtures. The company also sells Envirocrete with one-fifth recycled crushed aggregate. Although it saves virgin resources, it doesn’t significantly reduce the carbon dioxide emissions of the product.

Duxson’s business, Zeobond, makes Ecrete, a kind of concrete that completely replaces Portland cement with fly ash and slag. Known as a geopolymer or alkali-activated concrete, Ecrete produces two-thirds fewer carbon dioxide emissions than the conventional product. It uses other chemicals to kick-start the binding process and ensure the curing time is fast.

The first Ecrete supplier is located in Melbourne’s north-eastern suburbs, but Duxson anticipates that it will soon spread interstate. The product is also available in pavers and pre-cast panels. “The cost premium is between 10 and 15 per cent, but as we get to scale, we expect that price to come down quite significantly,” he says.

Magnesia-based concretes are another kind of lower-carbon concrete. Tasmanian company TecEco sells blended cements that include reactive magnesia as well as Portland cement and waste materials. When used in permeable concrete blocks, pavers and pavements, the company’s Eco-Cement absorbs carbon dioxide over the lifespan of the material.

This article was published in Sanctuary Magazine.

Community-supported agriculture

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Get the dirt on your vegies, and your farmer, with community-supported agriculture.

On Saturday mornings, somewhere in Ashwood in Melbourne’s south-east, a front yard looks like this: flocks of neighbours swap their backyard produce and chirp to one another over tea and cake. Kids buzz around. Then they all chat with their farmer.

It’s the Damper Creek Co-operative. About fifty families collect a box of organic vegetables, weekly or fortnightly, for $28 each. The boxes are delivered by the farmer, Rod May, from Captain’s Creek Farm near Daylesford. “He comes and hangs out with us for morning tea,” says co-op founder Katie Greaves. “People get to ask him questions about the food. The kids call him Our Farmer Rod.”

The vegie box group is a type of community-supported agriculture (CSA), where growers sell directly, and regularly, to eaters. “We want to know where our food comes from and we want to build a relationship with the people who grow it,” Ms Greaves says.

The co-op, run by volunteer members, began buying boxes in January. “We were concerned about our climate impact and dependence on fossil fuels,” she says. “I wanted food that hadn’t travelled halfway around the planet. I wanted to ride my bike to collect it, and to create a world where my young children get to know their neighbours.”

Members receive produce according to season. “We get vegies pulled straight from the ground, covered in dirt. We never know what we’re going to get, and people have really embraced that,” Ms Greaves says, noting the keen cookery discussion that followed delivery of daikon, an East Asian radish.

The co-op held an excursion to Captain’s Creek Farm, and plans to return for a spring feast and working bee. “Rod took us on a tramping tour around the vegie paddocks. The kids were hanging off his legs and asking questions about beetroot,” she says.

Ms Greaves is full of encouragement for people who want to create or join a CSA. “The key thing is to start small and keep it simple. Just go ahead – gather a group of interested people and begin making contacts.”

The Farm Gateway website, coordinated by Michelle Yang, is a great place to start. You can use the site to find active groups around the city or register your interest.

“The term ‘community-supported agriculture’ came out of America in the eighties,” Ms Yang says. There, it refers to groups that pay their farmer upfront for a season’s produce, rather than buying week-to-week. “It’s about supporting the farmer financially when they need it most.”

That kind of structure is less common in Australia, but can be invaluable for growers starting a scheme from scratch. However, vegie box groups such as the Damper Creek Co-op also give farmers a guaranteed market and close contact with their customers.

Ms Yang argues that CSAs bring householders benefits in spades: cheap, fresh, healthy food, with proof of its provenance, plus friendlier neighbourhoods and less transport, waste and packaging. “It re-establishes that sense of community around food, which we’ve lost in our society,” she says.

If a co-op isn’t for you, CERES Food Connect will soon offer a similar distribution scheme. They’ll buy and sort local, organic produce, then deliver boxes to a designated ‘city cousin’. Neighbours will pick up their produce from that house.