The retailer installed a set of solar panels on the roof of its headquarters in Cape Town and said that energy efficient projects have been a priority.
"We've done a lot of work on energy efficiency over a number of years and that was really the first focus from an environmental and a cost saving initiative," Justin Smith, Woolworths sustainability manager told News24 on the top of the building.
The solar panels represent a real effort at reducing energy costs rather than a marketing exercise, Smith said.
"We could have done one or two gimmicky green wash things at a store level, but A: It's very complicated, we don't often own the property; we're a tenant in the building. It would be a small installation so it would be a gimmick to be honest."
He explained that the roof installation which is estimated to produce 48 000kWh of energy savings per year was a way for the company to learn about its energy consumption with a view to rolling out the programme on a wider scale.
"We decided our head office is a good place to learn because we can obviously measure and monitor it very closely - we got the team here. This is really a pilot project, a learning opportunity for us.
"We have identified our distribution centres as a medium to long term opportunity for us for bigger installations, but we're busy looking at the right opportunities within that space," said Smith.
The green efforts at Woolworths have a long history and the company said it had saved nearly a third of its energy costs with a number of initiatives including management of water, lighting and refrigeration programmes.
"We've got the stage now where we've saved about 27% on relative energy use from the benchmark we set in 2004 just through the efforts of our teams over that time," Smith said.
The solar installation on the head office is monitored and there is a screen at the building's entrance so staff can see the energy being produced.
It also serves as a learning opportunity ensures energy security during the day. There is no provision for battery backup and the solar panels do not produce more energy than the building can use.
Despite this, the increasing cost of electricity has seen the return of investment period drop significantly from the project began.
"When we started the project the payback was just over nine years, but it's sitting at just over eight years now. With the Eskom increase it's just over seven years, so it's come down quite remarkably since we started the project," said Anton Kilian, Woolworths electrical engineer.
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