For the pay as you throw system, the best method for identifying the consignment of bag and bins is RFID technology
The Italian Ministerial Decree of 20th April 2017 on the pay as you throw tariff, in Article 3, introduces the issue of identifying users when the pay as you throw tariff system is implemented, establishing that this “tales place by assigning a unique personal code to each user”. More specifically, Article 5 sets the minimum requirements for the identification and pay as you throw metering for the quantity of waste:
"1. The user, to which the pay as you throw metering for the quantity of waste is associated, is identified directly and uniquely, by means of electronic control devices built into the container or bag with which the waste is consigned or by suitable equipment installed in special consignment points, such as containers with volumetric limiters. Recognition is by means of the user code or by other means of unique identification that allows the user code to be traced, also, for example, by means of the tax code of belonging to the user and its cohabiting family members."
And again,
"2. The pay as you throw metering systems must allow: a) identification of the consigning user by means of a code uniquely associated with that user or by identification of the user making the consignments; b) the recording of the number of consignments by detecting the put-outs of containers or bags or the direct consignment in containers with limited volume controlled opening or the accesses to the municipal collection centres made by each user.
The devices and organizational methods adopted must guarantee the recording of each single consignment, associated with the identification of the user or container, with indication of the time of collection."
Methods for identifying the user
Identification of the user that consigns the waste is by a barcode/QR code or an RFID tag put on the bin or bag for the general waste and this is associated unambiguously with each user. Both systems have their advantages and disadvantages:
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Barcode/QR code
The barcode/QR code is printed on the bag or bin: this is a very simple operation at very low cost, a few cents. However, the code is very delicate, it easily fades because of atmospheric agents – sun, rain – and, above all, it can break and deform when printed on a bag. Moreover, if on one hand the barcode or QR code requires reading on sight – you need to point exactly in its direction –, a not particularly immediate action during collection, there is the risk, on the other, that it can be read by third parties using an app or scanner on a smartphone.
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Tag RFID
The RFID is put on the bag, as an adhesive tag, or the bin, as a solid tag, requiring greater expense and entailing the risk that it can be removed, since it is attached. There are however many advantages: the RFID tag has a long life, similar to that of the container which it is put on – a bin lasts for up to 6 or 7 years, consequently the tag will have a similar lifetime. It can be read in any position – from top to bottom and vice versa, from left to right and vice versa, from the side – without extending the collection times. Finally, it can be read both by an RFID antenna fixed on the vehicle and a RFID wearable reader worn by the operator, leaving a wide possibility of choice to the municipality and the collection company.
The recording of deliveries in timely collection
After establishing whether to use the barcode or the RFID tag to identify the users, the municipality implementing the pay as you throw tariff must decide how to record deliveries, choosing between:
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Door-to-door collection and registration carried out by the operator
Door to door separated collection envisages taking the bag or bin directly from the user’s domicile. The consignments are recorded by the operator using a wearable device, identifying and counting the number of times the bin is emptied or the number of bags put out by the user. This method does not require any type of installation or maintenance; it is fast and reliable because it exploits the manual dexterity of the operator, whilst reading from close up guarantees particularly accurate data.
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Door-to-door collection and registration with fixed reader on the vehicle
The consignments are recorded by a fixed device mounted on the collection truck. Installing the antenna is however a complex operation that requires continuous maintenance costs because of the need to recalibrate the medium frequently. The pay as you throw reading bringing the tub or bag close to the device and then emptying the contents of the bin or throwing the bag into the truck body, requiring more time without taking into consideration that the reading can lose up to 10% of the data.
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Collection points (ecological islands)
Ecological islands allow the collection costs to be reduced, because it is the citizens themselves who consign the waste in the municipal collection centre, and offer a benefit in terms of ground occupation – there are no bins and bags near residences – and better street decorum. On the other hand, they are more prone to errors in data acquisition and do not allow you to check for any wrong consignments by the user.
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Controlled access rubbish bins
Like the ecological islands, rubbish bins fitted with controlled openings reduce the costs linked to collection and allow lower ground occupation. However, these also do not allow wrong consignments to be checked; moreover they have a high cost, requiring continuous maintenance, and it is more complex to operate them and the user must be instructed on how to use them.
The metering points in the RFID pay as you throw tariff system
The RFID pay as you throw metering point is represented:
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From the operator, who wears a wearable device for point reading
The wearable is an accessible cost and it does not require any installation; the close-up reading by the operator of the RFID tag or barcode put on the bag or bin guarantees high accuracy and reliability of the data. The operator can check any wrong consignments which are linked to wrong separation of the wastes by the user.
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By the waste collection vehicle, on which a fixed reading device is installed
Installing a RFID antennas is complex and requires high initial investment, as well as the costs linked to maintenance. The accuracy and reliability are average, but this system does not allow any wrong consignments to be checked.
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By the rubbish bins
The controlled access rubbish bin is fitted with a top cover that only opens with a badge or card to identify the user and record the consignments. It guarantees high accuracy and reliability, but does not allow wrong consignments to be checked, given that there is no operator.
From the comparison, it emerges that for the pay as you throw system:
- the best technology for identifying the consignment is radio frequency (RFID);
- the most effective method for recording the consignments is door to door;
- the most efficient metering point is the operator.
