Deposit return scheme for Scotland: summary

What materials will be collected? (Questions 1 to 6)

This refers to what kind of drinks containers should be included in the scheme in terms of the material they are made of.

It should be noted at the start of this section that 'plastic' is a catch all word for a number of related materials with similar properties. For drinks containers, the two main materials are PET (polyethylene terephthalate, the normal material for soft drinks and bottled water) and HDPE (high-density polyethylene, primarily used for milk and other dairy-based drinks).

The possible options for materials are broadly:

1. PET plastic only. This is the most basic option, capturing most soft drink and water containers. There are currently around 690 million PET plastic containers on the Scottish market, which a deposit return scheme has the potential to capture. This option recognises that this is not only a valuable material, but that there is significant public interest in reducing the number of these bottles ending up as litter. Pursuing only this option would, however, mean that large amounts of other valuable, and often littered material is not included.

2. PET plastic and metal cans only. There are currently 1.3 billion of these containers on the market. This would capture most soft drinks containers and some alcoholic beverages. Glass is a bulky, heavy container material, therefore excluding it from the scheme would simplify the system and reduce costs, particularly in terms of transport and any RVMs used to repay deposits. However, it would also lose a valuable material stream. If littered and broken, glass is a danger to people and animals. Excluding glass also risks distorting the market if producers chose to move over to glass packaging to avoid being included in the deposit scheme.

3. PET plastic containers, glass containers, and aluminium and steel cans. There are currently 1.7 billion PET plastic containers, glass containers, and aluminium and steel cans on the Scottish market, which a deposit return scheme has the potential to capture. This is the most usual mix of material included in deposit return schemes globally and constitutes the bulk of drink containers put on the market in Scotland. This option also captures a wide range of material that can form an unsightly and sometimes dangerous part of litter.

4. Both PET and HDPE plastic containers, glass bottles, and metal cans. There are currently around 1.9 billion PET and HDPE plastic containers, glass containers, and aluminium and steel cans placed on the Scottish market, which a deposit return scheme has the potential to capture. This is very similar to Option 2 but includes HDPE bottles. HDPE can offer value as a recycled material, and through its inclusion, the system would capture all dairy products, including fresh milk, flavoured milk and yogurt drinks.

5. PET and HDPE plastic containers, glass bottles, metal cans, cartons and disposable cups. There are currently around 2.5 billion PET and HDPE plastic containers, glass containers, aluminium and steel cans, drinks cartons and disposable cups on the Scottish market, which a deposit return scheme has the potential to capture. This builds on Option 3 with the addition of some types of material that are not included in any other deposit return scheme globally. The inclusion of these materials (cartons and disposable cups) captures the widest possible range of materials. Cartons in particular can be harder to recycle, however the main issue for their recycling is getting a large enough supply of them to process.

Table 1 shows the estimated tonnages of these materials dealt with by local authorities and the amounts they currently capture for recycling.

Table 1: Local authority household collection and recycling of target containers

Disposal costs for local authorities are variable but significant. In addition to household waste collections, local authorities also pay a cost for managing items disposed of in public bins or irresponsibly as litter. Non-recycled waste, including drinks containers that are not recycled, costs local authorities around £110 per tonne (including landfill tax) to dispose of. A tonne of mixed recyclate is also usually a cost for a local authority, between £14 and £60 depending on the material mix and contracting arrangements. Material diverted into a deposit return scheme eliminates these costs for local authorities. It is possible, however, that there could be an increase to the per tonne cost to local authorities of recycling what is left in the kerbside collections.

The scheme could also be designed to allow deposits to be redeemed on any containers that are placed in kerbside recycling or collected as litter. It would be important that any material extracted in this way is uncontaminated.

Another issue to be considered is the possibility of a deposit return scheme having unintended effects. For instance, excluding certain types of material could encourage producers to switch to that material to avoid having their products caught by the deposit return scheme.