In terms of efficiency, Waterless urinals are profitable due to the following reasons:
      The installation of a Waterless system is not more expensive than that of a common system. A Waterless urinal costs between 355 and 510 Euro, a common urinal between 360 and 1,300 Euro.
      What makes the decisive difference is the cost of operation. For common urinals, there are considerable water, sewage, maintenance and repair costs amounting to around 500 Euro a year. With Waterless urinals, merely the siphon has to be exchanged on a regular basis (about 2-4 times a year, 40 Euro per replacement).

Please take into account that if you decide for Waterless, you save both a lot of flushing water and high costs for the installation and maintenance of fresh water pipes. The cost reduction as to the disposal of urine really is huge.
      Depending on the place of installation, Waterless urinals mostly amortize within a few months and no later than after 2-3 years. (It is a fact that water and sewage costs are still rising. Thus, the period of amortization of a Waterless urinal will become even shorter over the years.)
      So much as to efficiency. Now we get to ecology.

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