Huge Industry; Huge Effect
Wineries are one of the largest agro-industrial activities worldwide, being also one of the main sectors responsible for producing industrial by-products and waste. In 2020, the global wine market size was valued at USD 417.85 billion, and is forecast to reach USD 825.5 billion by 2030. In 2020, the world wine production (excluding pomace and juices) was estimated to be 6.9 trillion gallons.
Due to the size of this sector in the worldwide industry, one of the principal environmental concerns is that the winemaking method produces, from top to bottom, an abundant diversity of remnants and waste, like vine shoots, grape pomace (about 14 million tons are produced every year), wine lees, spent filter cakes, vinasses, and winery wastewater. Many of these materials can be extremely damaging to the environment if released or disposed of without proper treatment, and the pure volumes deposited in landfills exacerbates serious problems. In fact, most landfills in the US are already nearing capacity.
Carbon Footprint
All agriculture and human activity, has some effect on the environment and winemaking is no exception. The wine industry at large is generally aware of its carbon footprint, but current practices still contribute to environmental impacts. The vineyards represent a relatively small share in these effects; it’s what happens after grapes leave the vineyard that constitutes nearly 80% of the industry’s emissions of greenhouse gasses.
The practice of producing and packaging wines in glass bottles contributes, directly or indirectly, to the lion’s share of carbon emissions within the industry. Transportation and distribution of wine, another significant element of the industry’s carbon footprint, is made less efficient when heavy glass bottles that cannot be efficiently packed are shipped around the world, traveling from the winery to cargo ships that cross the oceans, to distribution centers, individual retailers, and on to the consumer.
Prodigious Waste
An important corollary to the principles of sustainability is the need to view waste products as a valuable resource that can be managed to provide benefits for a range of activities, rather than a problem and a burden. Industrial wine production generates millions of tons of waste that should be managed and reused to reduce environmental damage and provide important resources that would otherwise need to be obtained through means that may also damage the environment.
Solid waste:
Grape pomace is the primary waste, or by-product, leftover from the winemaking process. It typically represents 20-25% of the original grape weight. In fact, 2.2 pounds of grape pomace is produced, on average, for every gallon of wine.
Grape pomace is primarily composed of grape stems, skins, pulp, and seeds, and many common disposal methods, like dumping in landfills, can trigger a wide range of effects. Those effects include contributing to climate change damaging the environment by polluting soils, disrupting vital ecosystems, and degrading fresh water sources.
Many wineries recycle it for use as a fertilizer or converted to silage as a nutrient-rich animal feed for ruminants, horses, rabbits, and poultry. Grape pomace is even safe for use in dog food, but even with all these established uses, the annual supply of wine grape pomace consistently outstrips the demand.
Liquid waste
The process of producing wine can use as much as 7 times the water as the final product, of which 70% or more ends up as wastewater. For example, a single 750 ml bottle of wine uses between 9.6 to 12.7 L of water (2.5 to 3.3 gal), generating 1.75 to 2.3 gal, or more, of wastewater.
Winery wastewater is acidic and contains large loads of organic matter, including lipids, polyphenols, sugars and tannins. When it’s released in concentrated forms, it can quickly damage soil and water sources - including surface and groundwater. Some wineries may perform some limited initial treatment on their wastewater before diverting it to municipal sewage systems, increasing the loads on their capacity and the overall cost of recovering water to a usable quality.
How Wineries are Responding
In response to rising customer concerns about environmental health and climate change, many wineries are looking into management techniques, new markets, and sustainable options for treating their own wastewater and handling solid waste.
Wineries may focus on minimizing their use of valuable resources, such as water, at the outset by adopting water conservation practices that range from increasing efficiencies in cleaning processes to minimizing spills during racking. Others seek innovative methods to reuse and recycle grape pomace and wastewater, viewing them as potentially valuable by-products rather than trash to be quickly disposed of.
Some wineries have sought to reduce their carbon footprint by adopting energy-efficient practices, such as setting up solar panels or wind turbines to power their operations. A few wineries, recognizing the enormous carbon emissions produced by transportation, have sought to move to thinner, lighter glass bottles and even alternative packaging.
