A growing group of important retailers have signed up to the Sustainable Wine Roundtable Bottle Weight Accord – an agreement to reduce the average weight of the 750-ml still-wine bottles they sell from the current average of approximately 550 g (about 1,300 g for a full bottle) to an average bottle weight below 420 g (1,170 g full) by the end of 2026.
So far they include the powerful Systembolaget monopoly of Sweden; Whole Foods Market and Naked Wines USA of the US; and Laithwaites, Lidl GB, Naked Wines UK, Virgin Wines, Waitrose and The Wine Society of the UK. Others are on the brink of joining them and producers are as welcome as retailers. They simply need to confirm to Sustainable Wine Roundtable (SWR) their commitment to the accord. SWR will collect data every six months to ensure progress towards this reduction target is being made.
The accord is based on the comprehensive research programme conducted under the auspices of SWR by Dr Peter Stanbury, outlined in Are lighter bottles in sight?
It is widely agreed that the production and transport of glass bottles is the biggest contributor to wine’s carbon footprint, even if its exact proportion differs according to a wide variety of factors including how far the bottles travel. Estimates of bottles’ contribution to wine’s total carbon footprint vary between 30 and 68%. But what is beyond doubt is that this carbon footprint could be reduced substantially if bottles were lighter. Stanbury estimates that by agreeing that at least 80% of their wine is packaged in bottles weighing no more than 420 g, these retailers’ wine-related carbon emissions will be cut by 25%.
Erroneous perceptions
Stanbury’s researches showed that many wine producers and those involved in selling wine still believe that their customers associate heavy bottles with wine quality. However, concurring with the international consumer research presented at this year’s MW symposium in Wiesbaden by Dr Armando Corsi of the University of Adelaide, Stanbury established that bottle weight is one of the least important factors when consumers make buying decisions. Far more important are factors such as price, personal recommendation and a familiar name.
Any assumption associating bottle weight with wine quality is plain wrong. Hardly any of the world’s most celebrated wines come in heavy bottles. The adoption of heavy bottles is a relatively recent marketing phenomenon and, as Stanbury said when presenting his report online to interested parties, ‘if your company thinks bottle weight is the number one factor [in selling your wine], fire your marketing department’.
Another brake on wholesale adoption of lighter bottles by wine producers is their belief that lighter bottles are more fragile and would therefore need stronger cardboard packaging, thus negating any reduction in glass-related carbon emissions.
Interviewing glass-bottle manufacturers and bottlers, Stanbury found that lighter bottles are perfectly durable provided they are well designed, with even distribution of glass and special attention to the points on the bottle that make contact with other bottles and filling equipment. Small adjustments may have to be made to bottling lines and the easiest win is to do away with the punt in the bottom of the bottle. In his full report Stanbury examines in detail each stage in bottle production, filling, packing and transport.
In Wiesbaden, Dr Chris Borman of The Park bottling plant outside Bristol, Britain’s biggest, reported that they have been using 330-g bottles for 10 years without any significant increase in breakages, even on lines that fill 400 bottles a minute. Bottle shape is important, he stressed, and the centre of gravity of a lightweight bottle needs to be relatively low.
This accords with my observation that the design of lighter bottles has improved enormously over the last few years. I can no longer tell simply by looking at a bottle how much it weighs. This used not to be the case.
Some wine producers told Stanbury that they found it difficult to source lighter bottles and they believe manufacturers find it more profitable to sell heavier bottles. But according to Stanbury’s researches, bottles are likely to be priced per unit rather than according to weight. As he points out, tweaks to selling price would generally be minor compared with the cost of building and, especially, maintaining a furnace 24 hours a day, 365 days a year at 1,500 °C.
Stanbury claims he found zero resistance to lighter bottles from bottle manufacturers, who are keen to retain glass’s supremacy over alternative wine packaging such as bottles made from recycled plastic, cans and bag in box.
The proportion of recycled glass, cullet, used in bottle manufacture varies considerably according to each country’s recycling rate: high in Scandinavia and Wales, middling in England and low in the US. The aim is to increase the use of cullet in bottle manufacture but care has to be taken since impurities in recycled glass can make bottles more fragile.
Reducing bottle weight should save the international wine trade considerable sums in terms of transport costs. You can see some examples of this towards the end of Bottle manufacturers, take note. In Wiesbaden we were told of a couple of other concrete examples of positive action. Burgundy négociant Albert Bichot, filling six or seven million bottles a year and exporting to 100 countries, reduced the weight of their bottles from 700–750 g to 450 g at the request of some of their customers, with no ill effects on their business. And the California wine brand Bonterra is apparently putting the associated carbon emissions on each of their wine labels.
It is to be hoped that the accord reached by these prominent wine companies will have a beneficial effect throughout the world’s wine trade.
For more detail, see SWR’s 47-page report on reducing wine-bottle weight, but note that this is just one of the initiatives in which SWR is involved; it just happens to be the easiest one to tackle initially. There are myriad alternative approaches to making wine production and consumption more sustainable, including adopting alternative packages to glass bottles.
What is vital is more consumer – and trade – education.
