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Grubby festivalgoers are testing a showering system that uses recycled water

”Get a good shower, with a clean conscience”, is the motto at Denmark’s popular Roskilde festival. At this year’s festival, which is an annual event, the Danish company Flow Loop is stress-testing a setup of the system, which would allow you to purify your own shower water, resulting in significant energy and water savings in private households.

”Even if you should pee in the shower, the system would still clean the water, making it safe to shower in, as the water is cleaned to bathing water quality before it reaches you. But of course you could also opt out of the recirculation if you need to pee,” says Simon Kolff.

He is the founder and director of Flow Loop – the company behind a system that can recirculate water while you are taking a shower. Calculations have shown that the system can save up to 85 percent of water and 75 percent energy in relation to an ordinary shower. This is an amount equivalent to approximately DKK 5,000 (EURO 671,09) for a regular household on an annual basis.

”Water is not something we are lacking in Denmark, but it is still makes sense to save. When we are testing the system at Roskilde Festival, it is to test it during times of peak demand,” he says.

In a normal household installation the Flow Loop system would pump the water directly from the shower floor to the drain with an integrated vacuum pump, leading the water through a system of filters and UV-purification before sending it out again through the showerhead. After the shower has ended, the system cleans itself and the water is directed to the drainage system as normal.

”People do not only shower because of hygienic reasons. If this was the case, having a shower would not take more than a couple of minutes. There is comfort in showering, but it is also a little silly that we are sending so much relatively clean, heated water directly to the drain, if there exists an alternative,” says Simon Kolff.

-Related news: A novel way to deal with rubbish festivalgoers

Retrofit and flow
Flow Loop’s shower panel is located on the floor. It is connected to the water pipes as any other fixture is and is locked to the wall with some wall plugs and a click system, that is located high enough up that it is does not disconnect the wet room membrane. In addition to this, electricity is connected.

”It is important for us that it is easy to install and maintain, because otherwise this type of system will have a very long pay back time,” says Simon Kolff.

”Doing this means that not all of the bathroom needs to be redesigned and we avoid problems relating to water leaks or damages, specific mounting and expensive installations,” he stresses.

The system can give a flow of 12 litres per minute, which is significantly more than the 8-9 litres per minute flow coming out of a regular shower. Of the total flow, only two litres a minute are made up of new water. The remaining 10 litres are recycled.

-Related news: Aalborg Sustainability festival

Tested at the Technical University of Denmark (DTU)
The system has been tested during the last six months at DTU’s department of water and according to Simon Kolff, there has been testing of different bacteria concentrations, shampoo, toothpaste and anything else one could imagine would be used in a shower. So far, the cleansing has worked very well in relation to the quality of the bathing water.

“The tests conducted at DTU have checked for highly concentrated bacteria cultures consisting of pseudomonas, enterococci, coli bacteria such as E. coli and others. We have confirmed that the system is suitable for showering, but not for drinking,” he says.

In addition, Simon Kolff stresses that during the first half minute and a half of a shower, the water is not being recycled, which is when the largest portion of the dirty water is drained as normal. It is also optional if you want to recirculate the water, you can choose not to do so, if, for example you are very dirty or do not want to recycle the water.

Previous experiences and administrative assistance from the Innovations Fund
A competitor to Flow Loop has already installed a similar system at Kristianstad Hospital to remove the circulation of legionella in the hospital’s shower system. Other systems are having an impact in Holland and Simon Kolff names South Africa and California as potential markets.

Flow Loop has amongst other funds received DKK 450,000 (EURO 60.397,82) from Denmark’s Innovation fund, which also saw Roskilde Festival as an interesting place to test the system.

“Denmark needs successful entrepreneurs to spread new ideas and create the Danish companies of tomorrow. By testing their technology at Roskilde festival, Flow Loop will conduct indispensable stress tests concerning the viability of their recirculating showers and they will receive valuable feedback about users’ shower habits and opinion on recycled bathing water,” writes Peter Høngaard Andersen from Innovation Fund Denmark.

Source: Ingeniøren

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