Carbon Ready Reckoner – Worked Example

Organic whole milk

This worked example shows how the WRAP Carbon

Ready Reckoner can be used to provide insight into

the carbon footprint of 2 pints of milk packed in an

HDPE bottle

Date: October 2013

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Itemise and describe all packaging components.

Consumer unit (primary packaging)

The consumer unit is the packaging the consumer takes out of the shop.

Some products are sold in collations, and the entire collation would be

regarded as the consumer unit.

This consumer unit consists of four packaging components:

HDPE plastic bottle;

HDPE cap with ribs on the side for extra grip;

cap internal seal with top easy open tab; and

plastic shrink sleeve label with full colour print.

The WRAP Carbon Ready Reckoner does not assess minor materials so

the plastic top tab is not included as a separate item.

To calculate the impact of changes, the number of consumer units

produced per annum is required. In this example, three million bottles

of milk are sold per annum. If this pack format were used for a range of

milk, then the total number of consumer units produced in the range

could be included in the assessment.

This bottle contains two pints (1.136litres) of milk which provides five

servings. Before removing the product it was noted that there was

significant head space which could be reduced.

Product information

Information required Existing pack

Product weight per pack (g or ml) 1136ml

Servings per pack 5

Number of packs per year 3,000,000

Pack description

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Secondary packaging

The secondary packaging is the packaging used to collate consumer

units for distribution, and is not intended to be sold with the product.

Typical secondary packaging includes corrugated board boxes, shelf-

ready display packaging, trays, and shrink-wrap film.

Secondary packaging is not normally used for HDPE milk bottles. They

are usually packed directly onto reusable trolleys.

Palletisation

The WRAP Carbon Ready Reckoner will calculate savings from improved

pallet utilisation, but does not include savings from changes in tertiary

packaging such as stretch-wrap, layer boards, and pallet top covers.

Changes in size to the consumer unit and secondary packaging may

affect the number of units that may be placed on a pallet or contained

within another shipment unit, such as a Pal-box. Details of pallet

configuration and transport will be needed to calculate distribution

savings from reductions in pack weight.

Packaging and transport data

Packaging materials and weights

Each packaging component is weighed to +/- 0.1g and the weight and

material recorded as shown on the table below. Reference can be made

to packaging specifications for weights, but actual pack weights should

be checked.

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Consumer unit

The HDPE bottle, cap, seal and label were relatively light and so

each was calculated from the total weight of a batch of 50

components.

Existing components – consumer unit

Component name Existing material Current weight (g)

Bottle HDPE bottles 26.2

Cap HDPE rigids (non

bottles)

1.5

Seal Aluminium 0.2

Label PE film 0.8

Secondary packaging

There is no secondary packaging associated with this pack.

Palletisation and transport data

In the case of milk, milk trolleys are used instead of pallets. In this

example, it is assumed that a standard milk trolley1 measuring 600mm

by 420mm by 1300mm with four stacking tiers is used.

This data is used to calculate the carbon impact of packaging changes

on transport. The data required is listed next.

1 http://www.she-ltd.co.uk/product/139

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Palletisation and transport data

Information required Existing

Type of vehicle used for delivery Rigid truck used most often –

capacity up to 17tonnes

Average one-way distance to

retailer or RDC (km)

150km

Number of consumer units / case n/a

Number of bottles per layer 35 bottles per layer

(7 by 5)

Number of layers per trolley 4

Number of consumer units per

trolley

140

(35 bottles x 4 layers)

Number of trolleys per vehicle 40

A range of delivery vehicles are used to ship to various RDCs, so most

typical vehicles were selected and average distances were calculated at

150 km (one way).

The vehicle options are limited to:

van (less than 3.5tonnes load capacity);

rigid vehicle (3.5 to 7.5tonnes load capacity);

rigid vehicle (7.5 to 17tonnes load capacity);

articulated vehicle (3.5 to 33tonnes load capacity); and

articulated vehicle (over 33tonnes load capacity).

In this case a rigid (>17tonne) vehicle is assumed. The number of

trolleys of this product that this vehicle will carry is 40.

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Pack improvements

The WRAP Carbon Ready Reckoner will calculate carbon savings from

various pack improvements. Each is considered as it applies to this

bottle of milk. This pack was compared with other two pint bottles of

milk on the market. Some data on the WRAP UK Packaging Benchmark

Database is available at:

www2.wrap.org.uk/retail_supply_chain/research_tools/tools/uk_packagi

ng_benchmark/index.html Packaging suppliers may be able to offer

alternative pack options.

Potential improvements to reduce carbon impact were considered for

each pack component. The factors included in the WRAP Carbon Ready

Reckoner are:

packaging weight;

product concentration – number of servings/portions;

secondary packaging or palletisation;

glass: colour and/or recycled content;

other materials: Recycled content and/or recycling rate; and

other changes (listed at end of section).

Packaging weight

Bottle: The best in class milk bottle is currently the Infini2 bottle (by

Nampak) which is 6.2g (23.4%) lighter at 20.0g.

Cap: Further light-weighting could be achieved by reducing the profile

of the cap. This will provide a small reduction of 0.1g (6.7%) to 1.4g.

Seal: Top tab on the seal could be eliminated and replaced by a side

tab; reducing the weight by 0.1g (50%) to 0.1g.

2 http://infinibottle.com/fact-figures/

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Labels: There were no opportunities for improvement on the label. A

smaller self-adhesive paper label may have less carbon impact than a

plastic sleeve, but once the silicone-backed paper waste is included, this

is not a better option.

Product concentration – number of servings

This product is sold as a fresh produce and any concentration would

change the nature of the product and likely to be unacceptable to the

consumers.

Secondary packaging or palletisation

There is no secondary packaging associated with this pack. No change

in milk trolleys is proposed.

Glass colour and recycled content

There is no glass content in this pack.

Other materials – recycled content and/or

recycling rate

If higher recycled content is available for other materials (apart from

paper and board) this may be used to calculate carbon savings.

There is currently no facility within the WRAP Carbon Ready Reckoner to

calculate the effect of increased recycling rate, such as glass jars with a

returned deposit value.

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Other changes

No other beneficial changes to this pack were identified.

WRAP Carbon Ready Reckoner –

Data entry

This section describes the process used to enter the previous

figures from existing and new packing components and

calculation of the relative CO2eq impact.

Logging in

The WRAP Carbon Ready Reckoner was accessed via:

http://www.wrap.org.uk/content/carbon-ready-reckoner-registration-

form and the correct Username and Password entered.

A new project was created by clicking on the green button “CREATE A

NEW PROJECT”.

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Definition

A description of the pack being examined was entered, with sufficient

information to ensure it is not confused with any other project.

Under “Which aspects of the packaged product are being changed?” the

box relating to packaging weight is selected.

The product measurement unit, weight, servings per pack, and number

of packs per annum were entered under the “Existing” column as shown

above.

Click green “SAVE” button then move to next page: Consumer unit.

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Consumer unit

This page allows the entry of consumer unit packaging components:

bottle; cap; seal and label. Click “ADD NEW COMPONENT” button.

Enter a description of each component, current material (from drop

down list); current weight, and new weight (as applicable) for each

component as shown:

When each component entry complete, click the green “SAVE” button.

It is always possible to edit or delete components later.

The figure for Current Recycled Content is automatically generated, but

may be changed, except for paper and board components. When

complete each entry may be viewed with the CO2eq figures already

calculated.

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Even if there is no change in weight, all components should be included

as they contribute to the final pack weight which affects the carbon

impact of distribution.

Component entries may be deleted D or edited E using the small buttons

on the right hand side.

As the milk bottles have no secondary packaging, the “No” radio has

been button selected. Click “Palletisation>>” to move to the next page.

If you wish to alter your selections it is possible to navigate by these

buttons or via the top or bottom navigation bars.

Secondary packaging

As “secondary packaging or palletisation” box was not checked at the

project definition page, this section has been excluded.

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Palletisation

This page allows the entry of changes in palletisation and calculates the

carbon savings from any reduction in pallet numbers and the reduction

in packaging component weights.

The type of vehicle is selected from the drop-down box Rigid (>17t) and

the one-way distance entered as 150km.

The calculated number of consumer packs per pallet is entered as 140

and number of pallets per vehicle is 40 for the Existing pack. As there is

no change, the same entries are made for the New Pack.

Clicking the green “SAVE” button will save these entries and calculate

the carbon impact and savings in the yellow boxes.

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The weight savings seen here are from the light weighting of the

primary packaging.

To view the final results, click on the “Results” button on the right hand

side to progress to the next page.

Results

This page shows the results of the calculations, and shows a 14.11%

reduction in weight CO2eq.

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In this example, we have made changes to the packaging weight, and

secondary packaging. The tick boxes above are a check of the

improvements included in the calculations.

The results below show the change in CO2eq between the Existing and

New packs, and demonstrate in a pie chart the relative impact of

different packaging components and transit.

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Note that the weights of the secondary packaging is now expressed in

weight/CU (consumer unit or primary pack). Clicking on the “Show

difference” on the top right hand side of the Consumer Unit table will

show the calculated savings.

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Before implementing any packaging change you will need to

ensure that changes will not cause adverse effects during

filling, processing and distribution. Pack image is always an

important marketing consideration.

While we have tried to make sure this worked example is accurate, we cannot accept responsibility or be held legally

responsible for any loss or damage arising out of or in connection with this information being inaccurate, incomplete or

misleading. This material is copyrighted. You can copy it free of charge as long as the material is accurate and not used in a

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on our website at www.wrap.org.uk

www.wrap.org.uk/crr