Climate change – wine's impact and what can be done to help

We’ve all done it, had that extra glass that we didn’t need with our body paying the price the next day, but what about the effect wine has on our climate?

Climate change refers to the long-term switch in both temperature and weather patterns. As an agricultural product, grapes - and therefore wine - are very sensitive to any changes in their growing environment such as precipitation and heat. The UN estimates that if we don’t make some changes, our planet will be 4-5C warmer at the end of the century, a very worrying statistic for vineyards already feeling the pinch of climate change. We all need to take action, though it’s not as simple as use caps not corks or only buy organic wine. To understand the wine industry’s main impacts on our climate we need to look at the whole winemaking process - from vineyard to shelf.


Land - current state of play

Globally there are 7.4million hectares in the world under vine, and this change in land causes huge effects on local ecosystems. Most vineyards are monocultures requiring land to be cleared of trees and hedgerows which before acted as carbon catchers. So, not only have vineyards taken away carbon sinks holes, they have added it to through potentially intensive farming techniques such as water, fuel and chemical fertilisers.

With temperatures rising, the need for water is increasing and irrigation is a common occurrence. Irrigation consumes energy, it removes water from other ecosystems and can disrupt the soil salinity around the vineyard if not handled correctly.

Due to the monoculture of vineyards disease is a constant threat with pesticides and herbicides common throughout the industry. Both have negative effects on ecosystems and their continued use leads to higher soil temperatures making it impossible for biodiversity to thrive. The introduction of fertilisers after WWII was too hard for many vineyards to resist due to their rise on yields, but have created ‘water dead zones’ due to surface runoff. They also cause a ‘treadmill effect’ and vines struggle year on year to support themselves which escalates chemical use, adding to manufacture emissions and fuel usage. This could lead you to researching ‘greener’ approaches by using organic fertilisers. Yes, they have less of an impact on the ecosystem compared to their synthetic counterparts, however a vineyard must use a lot more of them which increases the transport emissions and makes them unsuitable for many large vineyards. There is also a negative impact on the yield per acre, meaning an organic operation needs to clear more land for vines than a conventional vineyard.

Harvesting by hand or machine is a big debate in the industry but when it comes to climate impact, both have their own positives and negatives. Hand picking would seem like the eco-friendlier choice but many vineyards - especially in the UK where local labour is expensive – employ pickers from abroad and fly/bus them in which generates large amounts of CO2. For those sites that are too vast for hand labour mechanical equipment is necessity, but these machines have to be manufactured and fuelled, most of the time with fossil fuels like diesel. They also contribute heavily to soil compaction, effecting its ability to absorb inputs like water and nutrients. Soil stores greenhouse gases but when compacted it expels them creating another source of emissions.


So how can this effect on the land be combatted?

We are just in the vineyard and you can see what effects growing grapes are doing to both greenhouse gases and biodiversity. Vines are very sensitive to disease, so going suddenly from spraying to nothing won’t work. This is where employing precision viticulture and adding life to the vineyard can help reduce its material consumption and carbon footprint.

Planting hedgerows act as carbon captures, increase biodiversity and attract natural predators which protect the vines against pests, resulting in lower pesticide use. You can add bird boxes to nearby trees to help manage leafhoppers or try implementing pheromone traps. Introducing cover crops will combat erosion, stop monoculture (which aids disease protection) and increases filtration – captures rain, decreases run-off so less water and fertilisers are needed. These crops also increase organic matter which act as weed controllers when mowed. Most vineyards burn their prunings which release any caught carbon into the atmosphere, but instead they can be thrown on the compost where it increases organic matter.

Dry farming is not practical for many vineyards, but other actions can be taken such as increased organic matter, rainwater collection, natural wind breaks which limit transpiration and pruning management to increase shade can all aid water conservation. The fossil fuels used by machinery can be cut through lighter tractors and fewer trips. There has been a small uptake of electric tractors, and when powered through renewable electricity would have a huge effect to the vineyards carbon footprint. You could even use biofuel that can be made from winery by-products to power machinery.

Other forms of agriculture like grazing animals, or a lutte raisonnée approach would all limit machinery use and lower the vineyards carbon footprint. Changing the way a vineyard works is incredibly difficult and costs money, there isn’t one size fits all, every site is unique and it’s about finding ways that suit the producer, the vines and the environment.


Winery - is it any better?

Modern winemaking has seen a big shift from foot crushing to fully automated machines. Both metal and concrete emit huge amounts of carbon dioxide during their production and require a lot of electricity to run. The winemaking process is hugely influenced by temperatures, with significant amounts of energy being used to cool/heat tanks and maintain ambient storage. Most wineries will be pulling their energy from the national grid which is made up of over 50% fossil fuels. Even when applying biodynamic methods, you use a lot of energy, for example dynamisation can last over an hour and there is no chance that I could continually stir a pot of tea for that long!

On top of the energy use, tanks and barrels aren’t like that omelette pan that you never clean (which is why my omelettes taste so good!), you need about 3l of water to make every 1l of wine. This waste water is then very acidic and is illegal to dispose of in waterways, so it’s often tanked out at great cost. You also have pomace – seeds, skins, yeast left over that can head straight to landfill.


"Surely that's it in the winery?" Guess again...

Many people think that if I just crush some grapes I get wine but it’s so much more than that. Fermentation is the process where yeasts turn the sugars in the grapes to ethanol and carbon dioxide. Both are natural by-products of the reaction that takes place. This C02 is incredibly concentrated (one of the most known) yet wineries allow it to escape freely to pollute our atmosphere. I’m sure you have all heard of the term low-intervention or natural wine, words that are buzzing around the industry but make up a tiny amount of production overall. Most wines you see on the shelf have probably had something manufactured added to it. Whether it be cultured yeasts, sugar, sulphur or many of the ingredients permitted for fining and clarification (think egg whites or clay) these all need to be produced and shipped to the winery.


What can be done in the winery?

Energy use and its cost to both our wallets and the environment is a concern for us all, with many looking to cleaner sources and ways to consume less. Options like wind turbines or solar panels are both lower in carbon and are also a renewable source of energy. Even the smallest of changes like LED bulbs can offer efficiency and longer life spans, with rounded tanks even saving 5 degrees. Better insulation and winery design will also decrease energy use, as well as installing underground cellars, and ground-fridges. An alternate system for newer wineries is using gravity flow – where either levels or hillside can replace the need for a pumping system. This leads to lower electricity and water usage, and in some schools of thought is potentially better for the wine as the process can be less aggressive and is not as unsettling to the grape juice.

Around 20% of a grapes weight is waste, now that’s a lot of leftover sludge to get rid of! This pomace however, is rich in varies nutrients like sugar and amino acids which can be used for animal feed, distilled to make grappa, or even used as fertiliser for the vines. Water waste is also a huge issue for wineries. Using recycled water and even steam to clean equipment will lower usage. The best option for waste water include on-site treatment instead of tanking it off to an outside facility. The solids can be filtered to be put on the compost heap, and water can be recycled for irrigation, services (heat/cool) and cleaning.

With regards to the carbon dioxide lost via fermentation, modern (though expensive) systems are available which capture, clean and compress the gas so it can be reused, or sold. It can even be used to enhance algae production, which in turn produces biofuel that could be used for tractors in the vineyard.


Packaging & distribution

It’s Friday night and your relaxing with your natural wine feeling pretty stoked that you’re doing your part for sustainable living. Did you ever think what happens outside the winery walls though? Packaging and distribution account for a whopping 68% of a bottle of a wine’s carbon footprint, making both the vineyards 15% and wineries 17% slight in comparison.

Glass bottles get all wine lovers’ palate’s salivating; however, it is the biggest single contribution to carbon emissions from 75cl of wine. From the furnaces burning fossil fuels to produce them (the same temperature to a shuttle re-entering earth!) to the carbon cost of transporting that glass, I mean if you think about it how does it make sense to ship half a kilo of glass per bottle all the way from New Zealand? Although 70% can be recycled, you still need 30% extra sand to make a new bottle and the heat to recycle them is also high. It often seems crazy that glass is still top dog in today’s world, and with 99% of wine consumed in the UK imported it’s a huge cost to the climate. Once your mind starts rolling it’s hard to stop – roads wear quicker, tires need replacing on trucks more! Yes, you can invest in lighter bottles but you still have the space issue, as they take up 2.5x more space than if the wine was shipped in bulk.  

Cans of wine has seen a huge increase in the last few years and they are the most recycled drinks container in the world. They are stackable, lighter in weight compared to glass bottles but the carbon emitted through production is sky high (1-ton aluminium – 20-ton carbon). It's estimated that 80% is still in circulation but with an ever-growing population will we need to constantly mine more?


What about bottle closures?

Closures are another thought. Screw caps make up around 34% of marketed wine (90% of NZ wine and 70% of AUS wine) with many seeing them as eco-friendly due to the threat of cork trees. However, cork is harvested from the bark, the trees regenerate themselves so aren’t cut down. Yes, caps and synthetic corks can be recycled and natural corks cannot, but there are many companies that you can donate your cork to (recork UK) or you can even chuck them on your compost. Portugal is the leading producer of corks and a study carried out by Ernst & Young showed that a single cork captures 309g of carbon (562g Sparkling) enough to offset the whole process - even transport to the UK. It even showed that a glass bottle sealed with a cork has half the carbon footprint compared to one secured with a screwcap.

If cork closures decline, what will happen to the forests and the 4.8millon tons of carbon they sink? Will housing developments take up this space? The flip side is cork taint - another reason for the change. It’s hard to measure but this affects around 1-7% of wines today. Nobody wants this, wine down the drain, completely wasted and perhaps even a lost customer.

You may have also seen a rise in crown caps, mostly on Pet Nats. These caps, like beer can be recycled but often fall through the gaps at plants due to their size. Like cans they are also a manufactured metal, if more producers made the switch, and with the continued popularity of natural wines, increased mining would occur along with carbon emissions.

Buying wine online has been a continuous trend. It’s how I buy a lot of my wine, though I sometimes find myself filling up the hallway with bubble wrap and packing peanuts. Not ideal when 91% of packing materials end up in landfill. We have all been encouraged to eat and drink locally, but even buying English wine you have the issue of bottles going via road transportation, and compared to sea and rail it produces more emissions. It seems crazy that your bottle of Provence Rosé driven from the Rivera will probably contribute more emissions than your shipped Sauvignon Blanc from Marlborough.


What a minefield - so what should you do?

I’ve gone through the endless amounts of facts and figures on materials and transport, with everyone having different opinions on the most environmentally conscious way, and this is mine.

Here in the UK we consume more wine than we produce. In 2020 the OVI reported that bottled wine made up 53% of trade volumes around the world. Not ideal when you know the carbon footprints stats. By importing wine in bulk using methods like flexi-tanks (are recyclable or reused) we can cut C02 emission by 40% and lower fuel costs. Luckily many supermarkets do this already, primarily due to the fact that it’s cheaper, with the sustainability benefits coming second. Tests have been carried out on the wines stability and they don’t alter quality during transit, they even provide better temperature control compared to glass. How do I know if my wine has been bottled in the UK? Look for the W fronted code on the back. Now, this is looking at primarily climate benefits, bulk shipping has costs which include the loss of work at origin and sulphur is often used for protection during transport.

Even with their huge carbon footprint, bottles aren’t going to disappear anytime soon. They are the best containers for preserving fine wines and are even stipulated by some laws like Rioja and Champagne. Many people still have the mentality though of heavy bottles – better wine, with some producers not wanting to shift these monster bottles due to consumer views. Nevertheless, if we start to implement alternative packaging for everyday wine (95% of wine sold globally) which doesn’t require a long further age, it will create a huge impact to carbon emissions and help research towards even more sustainable options. Just think how many people buy their wine during the week only to drink it that weekend, is a glass bottled really needed?

PET (polyethylene terephthalate) bottles have come a long way with lower amounts of sulphur protection required, and an increased shelf life of around 24 months. They are durable, light, fully recyclable, and produce less carbon to manufacture compared to glass. Developers have even made flat bottles which allow for better stacking. It’s incredibly hard though to alter consumer views, with most seeing PET as an inferior product. They would however not be an option for age worthy wines or winemakers limiting/not using S02 use.

BIB (bag-in-box) wines have also seen huge improvements over last few years with increased uptake in supermarkets, but still have a lot to do with their perceived imagine. Many producers are also ditching the box leaving just the pouch in an effort to reduce unnecessary packaging. An un-opened 1.5l pouch has around 6 months life span, and once open can sit for about a month, saving any oxidation issues and a thrown half bottle of wine. They are durable, transportable and lightweight - hello beach wine! Compared to their glass counterparts they produce 60% less carbon, which does not include more deliveries or trips to the shops due to running dry…it happens to the best of us.  

Both PET bottles and bags are recyclable (as long as the cap on the bag is clear and not black which blends into sorting belts) but end of life disposing is still an issue. However, when weighing up the total process they have a lower carbon footprint compared to a 75cl glass bottle.


Great! What else?

Sparkling wine sales in the UK have continued to increase year on year, but certain regulations like Crémant and Champagne, require you to sell these bubbles in glass bottles. Prosecco is also obligated to be sold in glass, and as a nation we drink 36% of the world’s supply! That’s a lot of glass and emissions.

Using lighter bottles is the only option for certain wines until regulations are amended, with many already 7% lighter than they were 10yrs ago. Yes, it’s to do with history, but if we continue on track then there won’t be fine wine in our future, so is the pop really worth it?

There are some similar options though, for example Glera Frizzante (the grape of Prosecco) can be transported in bulk and sold in keg. In fact, these lightly sparkling styles are great suitors for bulk transport as the bubbles provide added protection from spoilage.

Sweet wines also throw a spanner in the works and carry a risk of re-fermenting in bulk transit due to the residual sugar. However, success has been shown in pouch format, with transport directly from winery.

If you're grabbing a wine on the go, then can is the way forward when it comes to convenience and carbon. Airlines are hubs for the single use mini wine bottles which go straight to landfill. Introducing cans would limit waste and see the aluminium be recycled and reused.

When going out for dinner it's often part of the ritual, ordering a bottle wine with your meal, or perhaps hearing the pop of champagne makes your Friday night. It’s going to be hard changing consumer habits, but even if bars and restaurants switch to a few keg wines, their carbon footprint would decrease.


Is buying wine online better?

Buying wine online is here to stay, it’s convenient, quick and the options are never ending. As consumers we hold a significant amount of power as we are the ones buying! Our consumption is a key driver to wine markets and its packaging. By buying cans, pouch, or PET bottled wine where we can, we are saving on fuel used in transport to our door. Companies can also assist by providing more sustainable options through plastic free, recycled cupboard boxes, electric deliveries and even offsetting their carbon footprint.


A few closing thoughts...

While the industry's carbon output isn’t as high as dairy farming, it is still a notable source. Current predictions indicate that due to the increase in temperatures, there will be a decrease of land by 50% which is able to grow premium grapes. Part of why wine is soooo awesome is that it represents the land and climate that it comes from. Are we on track for generic wines with the only difference being red or white? Do we really want to destroy this for our future generations?

Going to the supermarket you will see an unbelievable amount of wines to choose from, many under 5 quid. This in my view, fuels over-consumption, and a lack of connection with what you’re drinking. Yes, drinking wine produced from sustainable methods will often require more labour and lower yields resulting in higher prices. Consumers seem willing to spend some extra cash on their Fairtrade coffee beans, so why not wine? We cannot be ignoring the fact of what it will cost if we don’t invest in sustainability.

The Earth Beneath Our Feet Syrah 2017 is like a modern day message in a bottle, that showcases a hand written note on each label. All the wines are produced from the shared vineyard, where each grower manages their own patch of vines. This makes it possible for the site to be worked by hand and promotes a connection to the land so they limit industrial inputs in favour of natural resources like home-grown manure. Each grower is paid based on quality not quantity, building the incentive to produce healthy, full of flavour fruit. The production is small-batch with only 12 barrels of this wine produced. The growers' message on each bottle reminds you that someone has poured their heart and soul into creating this wine. This is someone’s art, their livelihood, and as consumers we have the duty to support originality and a sustainable industry. With this Syrah already at 15% ABV it makes me think about the future of my bottle and the people behind it.


Words by 'The Demeter Diaries'.


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