As many companies gradually wake up to the concept of business sustainability, a growing number are no longer content just to recycle paper and send out reminders to turn lights off at night - they're encouraging staff to be environmentally responsible at home, on the way to work and even on weekends.

"It's the next wave of environmental education," says Sophie Scott, the NSW Green Home Program co-ordinator at the Australian Conservation Foundation.

"I think a lot of companies have identified that it's a great way to engage staff in training and development. They might be buying sustainably in the office … but if you want to extend that to buying sustainably at home then people need extra skills to put that into practice. A staff member might not be the decision- maker at work but often they will be at home, so they can say, 'Yes, I'm going to purchase the organic food', or 'I'm going to purchase the rainwater tank'."

That is what Julie Reekie - the lending manager at the St George bank in Westfield, Liverpool - did as soon as her employer provided interest-free loans to staff as part of its Greener Dragon program. "I thought it was unbelievable because we were saving up to buy a water tank anyway, so when this offer came up I just jumped at it," Reekie says.

Under the initiative, which St George launched in December, staff can borrow up to $4000 for an annual travel pass, rainwater tank, solar hot- water system and energy or water-efficient appliances then pay it back, interest-free, over the next 12 months.

Reekie and her husband had a 4000-litre tank and pump installed in February and she says her enthusiasm for it is almost parental.

"The tank is full now, which is really exciting," she says. "You've got no idea was it was like at our house when we heard the water going into the tank for the first time. It was like having a baby: 'Can you hear that? My God, the tank's filling up."'

St George's group executive for human resources, Brett Wright, says the company initially believed staff would be keen because they could see they were saving money but "the feedback we've been getting is that it's more their desire to make some contribution to helping the environment … We've also had an enormous amount of other suggestions that people think we should consider in this category because they are environmentally friendly."

These ideas include green power, home insulation, swimming pool covers, bicycles and energy-efficient cooking equipment, and St George has linked up with WWF to ensure purchases under its interest-free program receive an environmental tick of approval.

"We want to do this in the right way," he says. "They [WWF] can validate some of these things for us when there are question marks over whether something is really environmentally friendly … I'm not saying we're going to do all these things, but the good thing is that people are engaging and it shows that there's a real interest here."

Earlier this year, the IT consultancy EDS put a carbon footprint calculator on its intranet. For five weeks staff in Australia and New Zealand were able to calculate their emissions and make a one-off payment, through the payroll system, into a tree-planting offset program run by CO2 Australia.

An EDS spokeswoman, Paula Driscoll, says it matched its employees' contributions dollar for dollar, and the money has been used to to plant nearly 8400 blue-leaved mallee trees on a property west of Narromine.

Driscoll says the company is now looking at other ways to help employees offset their emissions, including subsidising rainwater tanks and solar panels - "something environmental for their homes".

Energy companies are also getting on the bandwagon by giving staff incentives to take up green power. Employees at Energy Australia have received free packs of energy-efficient light bulbs, shower-timers and a 12 per cent discount on the company's Pure Energy green-power product, while Origin Energy staff can salary-sacrifice any electricity or gas bills they get from the company - and have, as an extra carrot for signing up, the possibility of winning a holiday in central Australia.

The toll-road operator Transurban, which has a stake in many of Sydney's private roads, is also pulling on an environmental hat. Not only is car pooling encouraged and space provided at the office to park bicycles, but the company buys yearly tickets on public transport for its employees, who have the next 12 months to pay the money back.

Diageo, the producer of drink products such as Smirnoff vodka, Guinness and Johnnie Walker whisky, has invited representatives from a local hardware store and the Visy recycling company to talk to staff at its Blacktown packaging plant about everything from home composting and water-efficient equipment to effectively reducing household rubbish.

Says Scott: "Corporate social responsibility is becoming more and more important, and as companies begin to audit their own carbon footprint they will then reach out to the employees: what are their employees doing at home and how can they educate them and help them make responsible choices at home?"

Earlier this year the Australian Conservation Foundation trialled its Green Home Program at one of Westpac's Sydney offices, running a monthly workshop between February and May. Westpac's Emma Herd says 40 employees signed up for the first two workshops - on water efficiency and sustainability in the garden - and then, as interest grew, a further 20 turned up for the last two - energy efficiency and "green" finance.

"That's completely against the trend with these voluntary initiatives," she says. "There was a lot of support for it."

So much so that Westpac plans to run the program again before the end of the year for up to 150 staff in the city centre. Herd says that the gain for the company in a program such as this is seeing just how important learning environment- friendly habits is to staff.

"In terms of what we get out of it, increasingly we're finding that employees want their employers to be assisting them in understanding what environmental issues are, how they impact on their own lives and what they can do to actually help to find a solution," she says.

It certainly works for Reekie, who stills enjoys the novelty of being able to water her garden whenever she likes and wash her cars with the hose. When she has paid off the interest-free loan for the rainwater tank, she plans to go back to her bosses at St George to sign up for something else.

"Once this is paid, then we'll go for the solar hot water," she says. "That's the next venture."