A new web guide will help straighten your irrigation

MELBOURNE has begun 2011 with record rainfall, but there’s no guarantee that the lush times will continue. The Bureau of Meteorology predicts that the La Niña conditions that brought the big wet will dissipate by wintertime.

By historical terms, the city’s dams are still low, and stage two water restrictions will remain at least until spring. That means householders still aren’t allowed to water their lawns from the mains. Gardens, however, can be watered by hand at any time, or every second day, at specified times, with manual and automatic irrigation systems. (You can find the full details about stage two restrictions on the Melbourne Water website.)

Geoff Connellan, from the University of Melbourne’s School of Land and Environment, says that just because we can water more often, doesn’t mean we should.

“The most common mistake people make in their gardens is to over-water, because they don’t understand how much water different plants need and how much moisture can be stored in the soil,” he says.

Together with Dr Jon Pearce and a team from the university, Mr Connellan has spent five years developing a free, online tool, called Smart Garden Watering, which helps you understand how to give your garden the right amount of water at the right time.

Using the website, you can calculate your water needs by entering all the details of your garden, including the location, size, slope and soil conditions, as well as the watering method and the types of plants and mulch.

The program draws on localised climate data and soil conditions, together with a database called the Burnley Plant Directory, which comprises over 1500 Australian and exotic plants.

Because it requires such detailed local data, the system is only available to residents in Melbourne and Geelong – for now, at least. “It does calculations for your postcode,” Mr Connellan says. “That’s important, because if you think of a garden in Sunbury and a garden in Olinda, they’re two totally different scenarios.”

The site is sprinkled with facts and features. It includes a Facebook application as well as maps, photos and forums that allow users to see other people’s gardens in their area, contact the gardeners and learn from each other’s experiences.

You can also plug in the details of your water tanks and see their likely storage levels throughout the year, based on the irrigation needs of the garden.

The results can be used not only to help you better understand your plants, but also to see what would happen if you re-designed your backyard. The website is interactive – you can toy with the settings and see how they affect your water consumption.

“It’s a sophisticated tool, but we’ve found that once people have become used to it, they are happy to play around with the options,” Mr Connellan says. “For example, if you choose drip irrigation or spray irrigation, or mulch or no mulch, you can see the consumption changing.

“That’s a very powerful graphical tool for a user. It encourages people to select efficient irrigation methods, and plants with low water needs.”

As a general tip, Mr Connellan recommends drip irrigation systems, underneath a layer of mulch of between 50 and 75 millimetres.

“Most people with plumbed watering systems can save about a third of the water they’re using, if they water wisely.”

Read this article at The Age online

To find the right solar panel, you can’t beat thorough research

THE rebate for residential solar panels has changed, yet again. From the start of July, the cash back available from the federal government will be cut by between $2000 and $2500.

Solar retailers and installers are experiencing a rush of demand before the fall. Many are already booked up until the new financial year, and those that aren’t yet are warning customers to get in quickly.

So if you’re considering purchasing a solar photovoltaic system, it’s worthwhile investigating your options now. But if you miss the deadline, all is not lost – prices may not rise too much.

The federal rebate is based on the trading value of ‘small-scale technology certificates’ (formerly known as RECs), which are created when solar hot water and solar electricity systems are installed. Presently, householders receive a credit of five times the certificate price, but the recent glut of installations has meant that the price – and therefore, the rebate – is lower than usual.

The multiplier will be cut to three from mid-year, and progressively reduced until 2013.

Russell Marsh, policy director at the Clean Energy Council, says the strong Australian dollar and falling costs in the industry mean that despite a smaller rebate, the price of a system won’t increase significantly in the second half of the year.

“Costs are coming down quicker than most people expected. The market is booming – there could be nearly 300,000 houses with systems on their roofs before the end of this year. We suspect [the rebate change] will have a small impact on price,” he says.

Mr Marsh says a good quality, 1.5-kilowatt system will set you back about $4000, out of pocket, depending on installation costs. For an average household, the payback period is around seven years.

If your head isn’t spinning already, you also need to consider the state rebates, known as ‘feed-in tariffs’. In Victoria, power retailers credit panel-owners 60 cents per kilowatt-hour for any surplus energy they feed into the grid (for the next fifteen years).

But new owners may soon miss out. “That premium tariff has a limit and we expect it to be reached within the next six months, or sooner,” Mr Marsh says.

Of course, there’s much more to consider than prices and rebates. To help, the Clean Energy Council has produced a detailed guide to buying solar panels. It covers basic information about the technology and its suitability for your home, together with a checklist for installation and comprehensive lists of questions to ask retailers and tradespeople.

For even more information, try the articles and podcasts put together by Choice.

Ingrid Just, from the consumer advocate, says a 1.5-kilowatt system produces about a third of the energy used by an average household.

“Firstly, get into the habit of reducing your energy consumption,” she says. “Australians tend to use a lot of electricity, so you should look at how much panel capacity you actually need.”

Before you buy anything, be sure to research thoroughly: ask your energy retailer about the tariffs it offers panel-owners and get quotes from a number of retailers and installers.

“Make sure you’re using an accredited installer and that any panel you consider meets Australian Standards,” she says. “Look for a warranty of 25 years from a company you trust.”

Read this article at The Age online

A mix of ingredients will put your compost on the top of the heap

GARDENING guru and landscape architect Costa Georgiadis can’t get enough vegie scraps. To feed his chooks and worms, and his compost pile, he imports peelings from neighbours.

“I’ve got a bin at the front and another one on the side street and my neighbours drop their scraps in them,” he says. “It’s a wonderful resource and everyone has it.”

Today marks the start of International Composting Awareness Week. To celebrate, Cultivating Community and Yarra City Council are holding a ‘Composter’s Composium’ next Saturday, May 7, at Smith Reserve in Fitzroy, from 11 am. The event will be a humus-inducing extravaganza, complete with live music, a workshop by Mr Georgiadis and (nearly) every kind of composting contraption known to urban living.

Lisa Coffa, senior waste officer at the council, says organic waste still comprises over half the kerbside collection, by weight. “It imposes great demands on our infrastructure and requires a lot of resources to pick up,” she says.

But that’s not all – every tonne of green waste in landfill causes about a tonne of greenhouse gas emissions. Ms Coffa says composting is a low cost, low-tech, local solution. Most councils, including Yarra, offer residents a discount on worm farms and bins, as well as advice on how to do it right.

“For most people, it’s very easy to convert green waste into something productive,” she says. “If you’re composting, you are better connected to your food source. It makes the link between what you purchase and what you throw away.”

For his part, Mr Georgiadis likens composting to cooking. “When you make compost, you transform the ingredients into something edible, with the help of microbes and worms and plants. You’re actually a chef, cooking your own chemical-free elixir.”

His first tip is to prepare well. “Compost gets a bad wrap when people do it half-heartedly,” he says. “You need to have the ingredients on hand, otherwise you’ll end up with a lasagne that only has pasta in it – and then it will become a seething, smelly, gooey mess.”

In the kitchen, get yourself a sealable container to stop vinegar flies from invading. In the garden, choose a shady spot and set up dedicated, covered spaces for several materials. You’ll need to mix the nitrogen-rich kitchen scraps with carbon-rich brown stuff, such as dried leaves, straw, shredded paper and cardboard.

Other items on Mr Georgiadis’ recipe include manure, green garden clippings, rock minerals and soil. Make sure you’ve also got a watering can handy and a corkscrew-style aerator (about $20) or garden fork for turning the heap.

“The key to any composting system is diversity, so every time you add something, add some of the other elements as well. Water it, turn it, cover it and let it do its thing,” he says.

Once the bin is full, you’ll need to leave it for about two months (but keep turning it every week) while you start a second batch.

When it’s done, to test if your mix is right, Mr Georgiadis suggests grabbing a handful. “If you squeeze firmly, you should see a little liquid running along the bottom of your pinky. If a whole lot of juice comes out, you need more carbon material; if nothing comes out, you need more water.”

Read this article at The Age online

Old electronics are too valuable to be dumped

IN Life Pscycle-ology, a short animation by Leyla Acaroglu, a forlorn mobile phone named Eric Sun laments his future stuck in a desk drawer. He is only one year old.

But poor Eric Sun’s plight is just the tip of the landfill. According to Greenpeace, e-waste now comprises five per cent of global municipal waste, nearly the same amount as all plastic packaging.

Ms Acaroglu, from Melbourne design consultancy Eco Innovators, says only one out of every 100 discarded mobile phones is recycled.

“The way we use and abuse high-end goods is very inefficient,” she says. “They contain hazardous substances that escape into the waterways or leach out in landfill. It’s wasteful and unfair to future generations – we’re gobbling up valuable resources so we can all have the latest iPad.”

Unfortunately, pollution and waste aren’t the only worries. Our throwaway electronics have side-effects all along the production line, from allegations that the illegal trade in minerals funds conflict in eastern Congo, to the dumping of e-waste on developing countries. (For more about the high-tech life cycle, see Annie Leonard’s animation, The Story of Electronics, and for background on conflict minerals, check out US charity, The Enough Project.)

“Australia is one of the only industrialised countries that doesn’t have effective end-of-life management for electrical goods,” Ms Acaroglu says. “And not only that, we also have no restriction on the hazardous substances used in those goods.”

But at least we’ll soon be able to get old TVs off the footpaths. Under legislation introduced to federal parliament in March, importers and manufacturers will be required to fund and run a national recycling scheme for televisions and computers, set to begin before the end of the year.

Ms Acaroglu says that while the product stewardship legislation is a crucial step, the goods themselves must be made differently. “Many of our products are designed to break. We really need to be creating long-lasting, interchangeable, upgradeable products,” she says.

“We need system service models – so that if you buy a computer, it’s not more expensive to get it repaired or upgraded than it is to buy a new one.”

In the meantime, Ms Acaroglu says householders can still minimise their gadget habit. First, unplug or switch off chargers at the wall – needless energy consumption accounts for a large dose of a mobile’s life cycle impact.

“Secondly, consider the consumption hierarchy,” she says. “Do you really need this product?”

If you really do, consider buying second hand or opting for the best quality, longest-lasting one you can find. Greenpeace’s Guide to Greener Electronics is helpful; it ranks the major brands’ performance on toxic substances, carbon footprint and e-waste.

“Seek out products that have longer warranties or service components associated with them,” Ms Acaroglu suggests. “Cheaper is not always better. And when something is really, truly no longer of use to you, make sure you recycle it.”

You can earn money for your old gizmos on eBay or from buy-back businesses (such as Mazuma Mobile or Cash a Phone), or give them away on Freecycle. There’s also a recycling scheme for mobiles, called Mobile Muster. Victorians can drop off old computers through the Byteback scheme, operated by Sustainability Victoria.

“Don’t leave them stuck in your drawer,” Ms Acaroglu says. “Get those resources back into the recycling stream.”

Read this article at The Age online

Beat urban heat with light surfaces and green spaces

AFTER a hot, still day, parts of the city can be up to seven degrees hotter than the surrounding countryside. Dr Andrew Coutts, from Monash University’s Centre for Water Sensitive Cities, says a phenomenon known as the “urban heat island” effect means that built-up zones are often warmer than rural areas, particularly after dark.

“Urban areas store heat during the day and slowly release it during the night,” he says. “Meanwhile, rural areas can cool rapidly because soil and vegetation don’t store as much warmth.”

The urban heat island effect is present all year round, but it becomes a problem during the hotter months. “Without low temperatures during the night, we don’t get to recover from daily heat stress, especially when we have daytime temperatures in the high 30s and 40s,” Dr Coutts says.

Victoria’s chief health officer found that the heatwave preceding the Black Saturday fires might have contributed to 374 people’s deaths, more than double the number who perished in the fires. “Heat stress is a big concern for vulnerable people, such as the elderly, the really young, and those with pre-existing medical conditions,” he says.

Dr Coutts says the heat island effect has three main causes. Firstly, dense, impervious surfaces, such as asphalt and concrete, trap and store heat from the sun. “In urban areas we have these complex geometries, like street canyons, where heat gets absorbed by the walls, roads and roofs,” he says.

Secondly, human activities, such as driving cars and using air conditioners, generate waste heat. And finally, because cities have fewer trees and less vegetation, they receive natural less cooling from shade and evapotranspiration through foliage.

The effect creates a vicious cycle, in which prolonged heat makes people switch on their air conditioners, which leads to more waste heat. Likewise, higher temperatures predicted under climate change will mean extra air con – thereby increasing both the urban heat island and greenhouse gas emissions.

So how can we sink the heat island?

To keep your property cooler, plant trees in your garden and harvest stormwater for irrigation with tanks and rain gardens. Minimise hard surfaces such as solid concrete; opt for gravel paths or porous paving instead.

Also, lighter colours increase the “albedo”, or reflecting power of a surface, so when you restore or replace your roofing, follow the example of whitewashed Mediterranean cities. “If you paint your roof white, it increases the solar energy reflected away from the surface,” Dr Coutts says.

It’s also possible to buy dark-coloured paints that cut the heat absorbed by your roof. Ceramic-based, heat-reflective coatings are available from a number of businesses, including Astec Paints and Colorbond Steel. “They reflect solar radiation in the near-infrared spectrum,” he explains. “This means you can keep your traditional roof colours, and reduce your energy needs and the urban heat island as well.”

Dr Coutts and his colleagues are studying the cooling effect of street trees, as well as the relative benefits of green roofs and high albedo surfaces. He says the tactics we need for the city-at-large mirror the task at home: we must make our buildings and roads more reflective, plant more vegetation and harvest our stormwater. We also need better public transport to reduce waste heat from cars.

“It’s mainly about smart urban design,” Dr Coutts says. “We can have quite high density living without the impact of urban heat islands.”

Read this article at The Age online