HOW TO IDENTIFY THE RIGHT WATER SOURCE IN THE PRESENCE OF AQUEDUCT (OR THE PUMP IS ALWAYS BETTER)?
The first step will be to let you identify the most correct water source among those available in order to size and build a correct irrigation system.
This statement may sound strange to you but it is the first step to save on water and / or electricity costs.
We must therefore understand :
- . what you already have and if it is convenient to use it
- . what problems there are / will be in its use
- . the convenience of connection
Old preconceptions immediately suggest the need for a well, thus confirming the use of the pump to reduce the areas and for fear of high aqueduct bills, but now with the latest professional materials the choice is no longer so obvious.
It will be necessary, if the aqueduct is present, to understand the capacity of dynamic range in order to be able to take it into consideration.
To do this, identify the tap (or connection) closest to the meter and then follow the measurement procedure indicated below.
In many cases, the use of the aqueduct is more than sufficient.
It will be useful to make a simple calculation to understand the monthly cost that you will have to bear: keep in mind that it will be divided into about 6-8 months of use and that you will not have electricity consumption, potential wear and / or maintenance problems related to the pumps.
Average supply of aqueduct at 2.2 bar = 19 liters per minute (which we will simplify with the abbreviation lt / min)
Number of zones in an average garden = 4 zones
If you have static sprinklers, the average operation per zone ranges from 10 to 15 minutes: let's consider 12 minutes for our example.
Average time of use of a system: from April to October (depends on the geographical area and the annual trend) and therefore we consider 7 months of use which is equivalent to approximately 210 days
Real irrigation days: we consider watering every other day therefore equal to half = 105 days
(an infinite debate can be opened but it would tend to be incorrect to irrigate every day because it facilitates the proliferation of fungal diseases and more)
19 l / min x 4 zones x 12 minutes x 105 days = 95,760 l => 96 cubic meters of water.
In case of aqueduct only, we consider an average cost of € 2.88 / mc (check your supplier here)
The result will be: mc 96 x € / mc 2,88 = € 276,48 => € 277,00 in 7 months => € 40,00 per month
Well, now you have a clearer idea in case of using only the aqueduct.
Pay attention to the diameter of the pipe where you connect: more and more often in new houses, small pipes are prepared for the external service such as multilayer pipes, in copper from 16 or smaller diameter. If you can, try to have at least a ¾ "pipe prepared to make the most of the potential of the water source.
But let's talk about the pump that needs a well ... If you don't use a tank (which we will see later) there are some elements to be seriously considered if not already present. It is necessary to inquire about the characteristics of the area, perhaps by consulting neighbors and installers, to know the depth of the water table (to understand the possible costs to build the well) and the possible presence of elements such as iron or gas.
It happened to me with a plant near a river (it would make you think of beautiful water at will) that to find water without the presence of iron, it was necessary to reach a depth of 80 meters having to use a submersible pump for a total cost of € 4000,00.
So you understand that with such an amount and the calculation made previously with the aqueduct, the time needed to "equalize" would be about 8 years (4000/40 = 100 months).
Having ascertained that you want or should do the well, get some guarantees because then the thing is very unpleasant to see.
Clearly this thing varies from territory to territory: if you have floors / sidewalks close to the green, they will inevitably get stained over time and you will have to treat them with specific products to return them to their initial conditions (depends on the concentration in the water).
All these elements have created a great confusion for you right?
Don't worry, let's proceed step by step.
Remember that more powerful pump does not mean better!
I always advise my clients who are building something new to do it in the simplest and most concrete way possible: do not start with a problem to be solved but prevent it.
The more things you put, the more things you can break!
Also in this case we can do the same calculation as before, substituting the cost of water for the cost of kW / h
Practical example :
If we use a 1 Hp pump on average it consumes 0.75kW / h
The average cost per kW / h is € 0.06 referring to a time slot 01: 00/07: 00 (also check your supplier here)
Using the data from the previous example, it can be seen that:
4 zones x 12 minutes x 105 days = the pump will work on average 5,040 minutes
5.040 minutes: 60 = 84 total hours x 0.75 kW / h pump consumption (1hp) x € / kW 0.06 hourly cost = € 3.78 => € 3.80 in 7 months
This calculation is valid in the event that we have good water and already a well, otherwise it will be necessary to add the cost for the construction of the well: for the first 10 meters, with good soil conditions, it is estimated € 400.00 for the following meters the price varies from € / mt 15.00 to € / mt 25.00 up to 25 mt. Obviously, if the well has particular territorial conditions, the costs will be different and here too I recommend that you get information.
total pump costs first year = € 3.80 + [€ 400 + (€ 20 x 10 additional meters)] = € 603.80
In the following years there will always be € 3.80 of electricity + € 25.00 for any maintenance of the pump (if you want to keep it efficient and silent).