A flick of the switch that will help save the planet -


Looking east on a cloudless night from the Blue Mountains village of Linden you can see a huge, bright patch in the sky. Turn west and the sky is dark.
A similar phenomenon illuminates the horizon 350 kilometres away at the Siding Spring Observatory near Coonabarabran. This astral glow, bright enough to rival the nebulas and galaxies that light the night sky, is Sydney.
The effect is even more powerful when standing in the city itself. Office blocks, bridges and structures such as the Opera House are so brightly lit they eclipse the hundreds of stars that would otherwise be visible.
Car lights, traffic signals and neon signs all throw light into the night sky, creating an artificial glow that is a pale imitation of what the sky really looks like.
Stargazers call it "light pollution", but there is a far more sinister edge to Sydney's sky glow. The huge amount of electricity wasted keeping the city ablaze long after most office workers have gone home is a significant cause of greenhouse gas emissions.
Those gases are changing the world's climate and weather patterns, creating droughts in some countries and floods in others, and pushing global temperatures slowly higher. Our addiction to artificial lighting is literally polluting the atmosphere.
Sydney is by no means the only culprit. Photographs taken from space by NASA show the world lit up at night, with the brightest glow coming from the wealthiest and most densely populated countries - north-east America, Europe, Japan and India.
But electricity is a bigger climate change issue in Australia than in other countries, because most of it is generated by burning coal, which releases carbon dioxide into the atmosphere.
Australia's commercial sector is responsible for about 10 per cent of the country's greenhouse gas emissions, the environmental group WWF Australia says. A fair chunk of that comes from building lighting.
It is a wasteful, polluting habit we can no longer afford, WWF says.
In partnership with Fairfax Media, the publisher of the Herald, WWF yesterday launched an ambitious campaign called Earth Hour, to encourage the commercial sector and the broader community to address climate change by using less electricity.
The aim is to get as many Sydney households and businesses as possible to switch off their lights for an hour on Saturday, March 31.
WWF Australia's chief executive officer, Greg Bourne, said a darkened Sydney would be a powerful visual statement from Australia's largest city about coal-fired electricity.

"It's about making a statement to the city and to the world that you can do something about this issue," says Bourne, who hopes to make Earth Hour a global campaign.
"In the movie An Inconvenient Truth, Al Gore talks about people moving from denial about climate change to despair, without stopping to take any action," he says.
"But we can take lots of small actions and we can do it with hope and fun and verve."
Sydney's Lord Mayor, Clover Moore, has urged all city businesses, workers and residents to support Earth Hour. "The three CBDs of Sydney, North Sydney and Parramatta make up Australia's largest business district, covering 30 per cent of the country's office space," she says. "All commercial businesses and their workers should join the community in supporting Earth Hour but also take concrete actions to reduce energy use.
"I believe this project is a big step on the way to cutting Sydney's carbon dioxide pollution."
Sydney's main providers of domestic and business power will measure the power saved and the greenhouse gas emissions avoided by turning off home and office lights and business signs.
The aim of the campaign is to cut Sydney's greenhouse gas emissions by 5 per cent by March 2008, the equivalent of taking 75,000 medium-sized cars off the road for a year.
WWF has targeted the commercial sector because it says it wastes so much electricity, particularly on lighting. The environmental group has estimated that the greenhouse pollution attributable to lighting could be cut by as much as 80 per cent if lights were turned off when buildings weren't occupied if and energy-efficient lighting was installed.
Some companies already have such energy-efficient technology. In the largest energy-efficiency upgrade to an office tower in Australia, the accounting firm PricewaterhouseCoopers installed a sensor lighting system earlier this year. When the first staff member walks out of the lift and to a desk each day, sensors detect the movement and turn on the lights. When no movement has been detected for more than 20 minutes, the lights go out.
The energy-efficiency consultancy firm Big Switch Projects has calculated that if all city office tenants saved energy at the same rate as PricewaterhouseCoopers, that would provide enough surplus energy to power 13,000 homes.
The company decided to spend $1 million to upgrade the lighting in its offices at Darling Park because lighting comprised a huge chunk of its electricity bill.

It will take five years to recoup the investment but the company has cut its total energy use by 15 per cent since the technology was installed in March.
Two years ago, the property group Lend Lease received the first five-star rating for energy efficiency from the Sustainable Energy Development Office for its 10-floor headquarters in Hickson Road.
It was the first big commercial building in Australia to use a passive chilled beam air-conditioning system, cutting its energy consumption by 30 per cent. Energy-efficient lights were installed, computers turn themselves off if they are not used for 20 minutes and motion sensors turn off the lights.
Across the water at Darling Island, Mirvac has incorporated water and energy savings in a new six-storey commercial office building, which has been leased by Fairfax.
To achieve a 4½-star Australian Building Greenhouse Rating, energy-efficient fluorescent lighting and motion sensors were installed. The cooling tower for the air-conditioning will draw water from a 90,000-litre rainwater tank, and water-conservation devices have been fitted to taps and shower heads.
But it is not just in commercial buildings where electricity can be saved.
Greenhouse pollution from households is one of the fastest growing areas. The population is growing, standards of living are rising and many homes - once shaded by a veranda or positioned to make the most of the weather - are now hot boxes in summer and eskies in winter. The great Australian dream home has become a greenhouse nightmare.
Bourne says it is important householders realise electricity consumption contributes directly to climate change. But he also wants people to understand that very small changes to electricity use, carried out by many households, can have a big effect on global warming.
"We are are targeting two outcomes with Earth Hour: engendering a sense of empowerment in people from all walks of life that they can be part of the solution, and creating a symbol with the lights going off that will go all around the world."
Using less electricity can be as simple as someone turning off the light when leaving a room or making sure electrical appliances are switched off at the wall.
Many appliances now use electricity even when they are doing nothing. The power used by appliances left on standby (when the switch of the appliance is turned off but it is left on at the wall) accounts for about 11 per cent of the electricity bill of the average home.

In some cases, leaving an appliance constantly on standby consumes more power than when the appliance is in use.
The Australian Greenhouse Office says $130 to $470 is saved for each tonne of greenhouse gas avoided, depending on the type of energy used.
Simple actions, such as drying clothes on a line instead of in a dryer, or washing in cold water, can cut greenhouse gas emissions and electricity bills.
But even when this information is available it can be difficult to change entrenched habits, especially in the home.
A Brisbane university student, Sarah Bishop, believes those habits will change only when people make the connection between their own electricity use and the massive changes being wrought on global climate and weather patterns.
Inspired by Gore's movie and the book The Weather Makers, by the Australian scientist Tim Flannery, the 22-year-old will leave Brisbane on January 27 and walk to Sydney to raise awareness of climate change.
Averaging 20 kilometres a day, she hopes to arrive in Sydney on March 31, in time for Earth Hour.
"I just hope I can show people that individuals can make a difference to this issue, that small actions collectively can make a difference," Bishop says. "It is really easy to talk about taking these steps [to cut electricity use] but in overriding our bad habits … the key is awareness.
"If you have one person in the household doing the right thing it is hard to keep it up when no one else is doing it. You need everyone in the household doing it."
Most of Bishop's friends did not at first understand why she wanted to walk to Sydney.
"But now they are always asking me questions and some of them are doing their own research [into climate change]."
She hopes the people she meets along the way will be similarly curious. But she wants to listen as well as talk.
"I am interested in what Australians are feeling about climate change, I want to find out what they think about it," she says.
Opinion polls show an increasing number of Australians are worried about climate change and a perceived lack of action by government to tackle it.
A Lowy Institute poll released in October found 68 per cent of Australians believed climate change was a "critical threat" that should be addressed immediately, even if this involved significant costs.
As the institute's executive director, Allan Gyngell, observed, climate change "has become mainstream; it's no longer just an issue for Greens and people dressed up in koala suits".

For observatories such as Siding Spring and the Sydney Observatory in the heart of the city, Sydney's spreading sky-glow is an increasing problem.
If the state and federal governments were serious about tackling climate change, they would already have reduced public lighting, says Dr Barry Clark, of the Astronomical Society of Victoria.
In a paper he wrote for the National Australian Convention of Amateur Astronomers in May, Clark said artificial sky glow from cities could be detected from hundreds of kilometres away.
"If the present unsustainable growth in outdoor lighting continues over a few more decades, many existing Australian dark-sky sites will be afflicted by sky glow," he says.
Unless the growth in outdoor ambient light at night was stopped or reversed, Siding Spring would eventually experience unacceptably bright levels of sky glow that would make the observatory's work almost impossible.
"The costs of forced relocation to more remote sites would be worrying for the various national governments and organisations involved," Clark says.
There are problems closer to home, too. The constellation of Orion, commonly known as the saucepan, began to appear in the night sky earlier this month. It rises higher every evening and should remain visible until May. But it is getting harder to see every year, says the curator of the Sydney Observatory, Dr Nick Lomb.
"If we did not have any city lights we would be able to see the Milky Way, too. You can see it from the Blue Mountains in a dark area. It is quite beautiful," Lomb says.
The city's lights imply we have energy to burn but they ruin the fun for stargazing and contribute to climate change.
"We are the losers because of the city lights. Children, especially, are the losers. Gazing at the stars should be part of our culture," Lomb says.
"My hope is that people will eventually realise that by having all those unused lights on we are wasting a lot of energy."