The actions we perform every day, from the simplest to the most complex, can also be evaluated from the point of view of their impact on the environment.
Focusing on the most common, we turn our attention, for example, to turning off the tap when we brush our teeth, switching off lights when they are not needed, or doing the laundry at off-peak times.
But often overlooked is an action that has a significant impact, every day of the year, on our consumption, and that is when we go to the bathroom and ‘flush’.
Considering a family of four, how much of an impact can such an action have in terms of water consumption?
How many cubic metres are saved by, for example, reducing the flush volume from 9 to 6 litres, rather than 4, and how can water consumption be reduced without compromising on bathroom hygiene?
Choosing a low-water-consumption toilet cistern has a huge impact on a family's consumption: a wise choice can translate into concrete financial savings, as well as contributing to the protection of resources.
Analysing the scenario shown above, let us first see how much water is used by the household in question during a typical day. Let's assume that each member of the household uses the toilet three times a day, flushing the total flush once and the partial flush twice.
HOW MUCH DOES A TOILET CASSETTE CONSUME TODAY?
Since the typical volumes of today's models are mainly 6 litres for the full flush and 3 litres for the half-flush, each member of the household will use (6 l x 1 + 3 l x 2) = 12 litres of water per day; thus, in one day the household in the example uses an average of 4 x 12 = 48 litres of water, which in a month becomes 48 l/day x 30 days = 1440 litres; starting from the daily consumption, we can also calculate the annual requirement, which is 17. 520 litres, or if we want 17.5 cubic metres of water per year per household.
If we consider older flush cisterns, we measure a consumption of up to 9 litres for total flushing, and we can easily estimate that the same group of people would consume more than 26,000 litres of water in a year.
So what in concrete terms is the difference compared to the 6/3 litre version? In one year, this gap reaches almost 10,000 litres, i.e. the WC ‘consumes’ in one year two and a half times the amount of water that would be used by a higher-performance cistern; and of course, the costs also become two and a half times higher.
These are consumptions that give one pause for thought, especially since in most cases drinking water is used; but how is it possible, from a technical or practical point of view, to reduce such consumption?
Over the years, various companies in the sector have developed technological solutions that allow significant water savings, while at the same time ensuring that the toilet bowl is properly cleaned. These solutions are mainly the result of investments in research and development by both manufacturers of ceramics and manufacturers of flushing systems, because these are always elements that work in symbiosis.
Indeed, there are rinse cisterns that require 4 litres of water for total flushing, and only 2 litres for partial flushing.
Considering the 4/2-litre version, and recalculating the annual consumption of our typical family, we see that this is equal to (4 people x (4x1 + 2x2)) = 32 litres/day, which in one year will become 32x365= 11680 litres, i.e. 6,000 litres less water than the already high-performance 6/3-litre version and a good 15,000 litres less water than the 9/4.5-litre version assumed as a starting point. Clearly, a flushing cistern with these characteristics must be combined with a toilet that guarantees proper cleaning even with an extremely small volume of water.