We know who turned water into wine. Now, reports the Timesonline, Australian scientists are going a step further – they are turning wine and beer waste into water to generate electricity.

Miracles aside, man still relies on a lengthy process to make alcoholic drinks that produces tens of millions of litres of waste water a day. Scientists at the University of Queensland have developed a way of recycling that waste twice over. The technology involves sugar-consuming bacteria that “clean” the water and produce energy in the process.

After laboratory tests, they are now building a chemical reactor on the site of Australia‘‘s largest brewery, Foster‘‘s in Brisbane. It is expected to generate enough electricity to power a large household around the clock by using a fraction – about 2,500 litres (550 gallons) – of the 2.5 million litres of waste water the brewery generates each day.

If the venture succeeds, the scientists believe that the technology could be expanded and used at many breweries, wineries and food-processing plants to generate electricity.

The potential for electricity generation is enormous. A larger chemical reactor capable of harnessing all the waste from the Brisbane site would produce enough electricity to supply about 2,000 households. At the heart of the process is a microbial fuel cell – essentially a battery in which bacteria consume rich, water-soluble brewing wastes such as sugar, starch and alcohol. The bacteria release chemical energy from the organic material, which is then converted into electricity.

Jürg Keller, leader of the Queensland University project, told The Times: “Waste material is actually a very good source of chemical energy that we can convert into electrical energy or gas energy.

“It is, for the first time, possible to generate electricity directly out of the waste that‘‘s in waste water.”

There are other research projects around the world exploring similar technology but, Professor Keller said, the Queensland project was believed to be the first ready to move out of the lab and on to an industrial site. The 2,500-litre fuel cell to be erected at the brewery will be 250 times bigger than a prototype that has been operating effectively at the university‘‘s laboratory for three months.

Asked if he expected that a larger cell would be built to harness the electricity-generation potential of all of the waste water produced by breweries, wineries and food processors, Professor Keller said: “Oh, for sure and that‘‘s the next step.

“We have to iron out a few issues at this [2,500 litres] scale, obviously, and then hopefully we can take it to a larger scale again.” The technology is particularly attractive to brewers and winemakers in drought-hit Australia, where water is becoming increasingly scarce and expensive.

The country‘‘s many coal-fired power stations also make the nation one of the world‘‘s leading greenhouse gas emitters per capita.

The benefits promised by the technology are twofold: it successfully prepares waste water for recycling without using the large amounts of electrical power that traditional treatment systems require. Therefore, it not only saves on electric power use but also generates it.

And the water, at the end of the process is good enough to drink, according to Professor Keller, who has sampled it.


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