The construction of a viticultural building or wine cellar and the choice of machinery associated with the design of facilities imply in-depth reflection, particularly with regard to the economic and qualitative aspects as well as the safety of those using the machines. As well as the practical side, taking sustainable development into account requires a reflexion about impact of the cellar’s design and operation on the greenhouse effect.
In the past, natural means were always used to take advantage of coolness and warmth.
Building design, involving efficient insulation and sometimes completed with original solutions (green roofs or walls, underground heat exchangers, etc.) And alternative energies (solar, geothermal, biomass…) Is part of this eco-design process for wine cellars.
While the various traditional methods cannot be used in every situation, eco-technological progress, besides economic measures, means that it is possible to envisage developing.
These aspects, together with landscape integration, contribute to promoting the cellar’s environmental image. It is possible to incorporate an original and pioneering approach, besides architectural choices, in communications and wine promotion measures.
At the same time, experts are predicting a significant rise in the price of water and energy, which will contribute to raising wine production costs.
The aim the communication is to establish an overview of available solutions illustrated with examples from different wine-producing regions of the world.
Energy and the greenhouse effect
As far as energy is concerned, the stakes for future generations are multiple. From an environmental point of view, the combustion of fossil fuels (petrol, coal, gas) increases the amount of carbon dioxide in the atmosphere, accentuating the greenhouse effect. Sustainability also takes into account the availability, over the next few decades, of these non-renewable fossil energies.
Mechanisation in viticulture, as in farming generally, developed during the middle of the 20th century. Quite apart from the direct consumption of energy (tractors, grape harvesting machines, transport), intermediate viticultural products (fertilisers, plant protection products) are also responsible for increased energy consumption.
In the cellars, wine growers often had empirical knowledge of the importance of thermal conditions for wine production. They adopted every possible means of benefiting from natural cold or heat (underground cellars, open during the winter, air vents orientated in relation to exposure or dominant winds). Low winter temperatures were exploited to ensure the tartaric stabilisation of wines. However, wine-making remained very dependent on the immutable cycle of the seasons and on the year’s weather conditions. Recently, qualitative imperatives, the need to ensure the perfect biological and physico-chemical stability of the wines, the shortening in cycles of vinification and the building of cellars at ground level have all contributed to the widespread adoption of thermal applications throughout the wine-making process.
The use of energy and additives, the energy recycling of by-products and waste, the design of buildings and equipment all form part of the environmental and sustainable imperatives of grape production and processing systems.
The environmental impact of oenological processes is primarily linked to waste effluents from cellars that may endanger the biological balance of rivers, particularly during the harvesting period. The organic elements produced by wine-making activities favour the development of micro-organisms that use up the oxygen dissolved in the water, to the detriment of the ichthyofauna. The effects of the concentration of production units and, paradoxically, the development of wastewater treatment plants in viticultural districts, often saturated at harvest-time, have highlighted the environmental risks of cellar activities.
The fight against pollution in wineries depends on two complementary approaches. Upstream, the production processes need to be adapted to reduce the waste load and ensure the optimal management of water. This approach can be summed up by the phrase “the easiest effluent to eliminate is the one that is never produced”. It is based on an optimisation not only of technological design, but also of organisation and training.
Downstream, the treatment of cellar effluents, carried out individually or collectively, can be considered with the use of various individual or collective systems: evaporation, spreading, aerobic or anaerobic biological treatment..
By-products and waste
The management of waste is a central theme of reflection in sustainable development, both in terms of its actual management and of the depletion of resources linked to their production.
Historically, the proportion of waste produced by the vitivinicultural sector has regularly increased. In addition to bottles and their packaging, the packing used for oenological and plant protection products and the waste related to vinification processes (descaling solutions, filtering media, etc.) Are also part of the environmental challenge facing wineries.
As far as by-products are concerned (marc, must deposit and dregs), there is a long-established system of valorization through distillation. The same is true for tartar crystals, transformed into tartaric acid. Similarly, composting is a means of returning organic matter to the soil, part of a sustainable ecological cycle that limits the greenhouse effect. Indeed, composting is one of the foundations of organic farming.
The optimal management of these by-products and waste depends on several techniques: quantitative and qualitative inventories, reduction at the source, selective collection and recycling.
Water is indispensable to life on earth. It dissolves and transfers oxygen, carbon dioxide and the mineral salts that are vital to living organisms. The level of precipitation, combined with the temperature, define the characteristics of terrestrial ecosystems. The total quantity on the planet is estimated to be about 1.4 thousand million cubic kilometres. Most of this (97.4 %) is salt water. In parallel, most of the fresh water exists in the form of ice or snow.
As far as irrigation is concerned, the use of irrigation control systems combined with estimates of hydric stress and relative evaporation make it possible to limit water consumption while reducing the risk of increasing soil salinity.
Water is also used in viticulture for washing sprayers and vinification equipment. Training and raising the awareness of personnel and optimising washing systems and procedures can help to limit consumption.
Methods of recycling or re-use (rainwater, cellar or spray effluents) can also be incorporated into the sustainable management of water resources.
The aim of spraying is to cover a zone of vegetation, a soil or a weed with a given mixture, under the most suitable conditions for protection or destruction. In addition to the agronomic considerations, spraying must take into account, to an ever greater degree, environmental constraints and safety of use.
The final objective of spraying includes optimization of the dose, in proportion to the plant cover, and limitation of drift (the quantity of spray mixture that misses its target). The loss of product may result in a transfer into the air and the soil.
Generally, targeted application (one side at a time) adapted to the stage of development of the vine limits the risk of drift, compared with “open” spraying (oscillating cannons or helicopters). Antidrip devices can also prevent the loss of mixture when the pressurised circuit is turned off.
In parallel, the need to protect users and avoid one-off pollution incidents calls for the training of personnel, an adaptation of practices and equipment (product storage, filling area, management of wash water). And food safety considerations also justify the traceability of treatments.
Protection of the vineyard
The introduction of the plagues came from America (powdery mildew, downy mildew and phylloxera) during the second half of the 19th century contributed to profoundly change the habits of the campaigns. Some vineyards will disappear temporarily or permanently. Sometimes these scourges dived winemakers in deep disarray that only prayers and local superstitions have attempted to mitigate. In the middle of the twentieth century advances in chemistry have helped an important development of the synthetic products in the protection of the vineyard. If at first, these new molecules translated into spectacular results about the diseases and parasites, the phenomena of resistance and the risk of residues have highlighted the interests of reasonable protection.
In addition to the phenomena of resistance, the use of plant protection products could drive by changing the biological balance and destruction of the auxiliary, to the emergence of new pests. Such was the case for weeding with the outbreak of weeds immune to new herbicides. Similarly, the use of insecticides, led to a decrease in the population of the typhlodromes, leading to the development of dust mites.
Built-in protection relies on the use of alternatives to chemical control methods and tools of decision (observation, counting, disease modeling). Different research focuses particularly on the understanding of the mechanisms of defence of the vine.
Runoff and erosion
Most hillside vineyards are confronted with problems of runoff and erosion. Over the last few decades, these phenomena have been exacerbated by developments in viticulture: longer rows, weeding, restructuring of the hillsides (destruction of hedges, shrubs, walls, etc.).
In the past, vine growers had, often empirically, developed solutions to limit the source of erosion risks. Unfortunately, the imperatives of productivity and the introduction of mechanisation have, under certain conditions, overridden these ancestral practices. In keeping with the specific situation, a compromise must be found between the need to adapt the planting and layout of vineyard plots to the constraints of mechanisation and the concern to regulate surface runoff as close to the source as possible. For vines on steep slopes, these imperatives often justify the introduction of plant cover or a surface layer of mulch (reducing runoff and improving the soil structure). As a complement, hydraulic works (ditches, stoned or concrete tracks, settling basins) facilitate the outflow of rainwater. All these measures need to be incorporated into a policy of harmonious landscaping.
Men have been exploiting the soil, the “skin of the earth”, for thousands of years, without always knowing its diversity and functions. It is widely defined as “the superficial part of the earth’s surface created from a combination of mineral products from the continental disintegration of rocks and organic molecules from the decomposition of living matter (microbial, vegetal and animal)”. If its traditional dimension as physical support and reservoir of water and mineral elements can be perceived intuitively, its microbiological diversity and its role in the cycles of water and matter are still often unrecognised, notably in strategies of cultivation.
Soil-related factors limiting agricultural productivity have been mastered with the use of enrichment, fertilisation, mechanisation or land improvement (drainage, irrigation). But this success of modern techniques has its own limits; soil compression and erosion, the reduction in biological activity and the transfer of pollutants are some of the new preoccupations of agronomists.
The soil constitutes a heritage that needs protection, and this was recognised by the council of europe in the european soil charter (resolution 72/19 of 26 may 1972), which specifies that “soil is one of humanity’s most precious assets. It enables plants, animals and humans to live on the surface of the earth”.