In Chile, the path from vine to wine is easy to trace: Grapes are grown, harvested, fermented and then bottled and shipped around the world.

The environmental cost of that undertaking is harder to measure. But Chilean winemakers have little choice than to embrace the challenge.

If they don’t, there could be no place for their merlots and cabernets on international shelves.

Major retail stores and governments want to know just how much fine wines contribute to climate change. And they want consumers to know too.

That means offering a calculation of just how much greenhouse gas is emitted per glass of wine.

Chile was the fifth-largest wine exporter in the world last year and is rapidly expanding. The United States and the United Kingdom are by far the main destinations for its wine, followed by the Netherlands, Canada, Brazil and Japan.

In 2012, the European Union will require all products to carry eco-labels, and next year France will attempt a yearlong trial with carbon footprint labeling. Japan is also experimenting with a carbon footprint label for dozens of beverage and food companies.

In December 2007, the government export promotion agency ProChile saw a story from the BBC urging consumers not to buy Chilean cherries because they come from far away and contain a great deal of CO₂. That sounded the alarm that Chilean exporters needed to start paying attention to this issue, said Paola Conca, head of the Sustainable Trade Department at ProChile.

And Chilean wine producers are now onboard, working to measure the carbon footprint of their operations and reduce, or offset, their emissions.

After doing measurements, they realized they needed to focus most of their efforts on the energy-intensive post-harvest stages. A study commissioned last year by the governmental Foundation for Agrarian Innovation found that bottling and storage were the biggest causes of emissions in the wine industry. Several vineyards also found that sea freight contributed significantly.

So far no Chilean wine has yet to boast a carbon footprint label, but many vineyards have been certified carbon neutral, meaning they have offset their greenhouse gas emissions by investing in sustainable energy projects around the world.

Vina De Martino, one of Chile’s leading organic wine producers, measured all of its carbon emissions in 2007. Two years later, it launched the first carbon-neutral wine in Latin America and became the first carbon-neutral winery in South America. It reduced its emissions by building a wastewater treatment plant and by buying carbon credits.

Cono Sur, also an organic producer, invested in waste gas power in Germany and wind power plants in Turkey and India to compensate for its greenhouse gas emissions during product delivery.

As Chilean wine companies examine their environmental impact, they’re realizing the most urgent target is energy efficiency.

Vina Errazuriz, for instance, built two storage facilities with skylights and large windows to save energy; one of them has a geothermal warming system. Vina Los Vascos installed thermosolar panels and Solatubes on the ceiling of its storage rooms, saving 50 percent of energy costs during the winter and 100 percent during the rest of the year.

And many vineyards, like De Martino, Emiliana,  Cono Sur and Concho y Toro — Chile’s main wine producer and exporter — have switched to lighter bottles that use recycled glass and labels.

“It isn’t cheap, but it’s an investment priority. It will be ultimately compensated, because consumers, especially in Europe, care about which producers are neutral or are working to reduce their emissions,” said Alejandra Lapostol, head of the sustainable development committee at Cono Sur.

“The industry is fully aware that if we don’t measure our carbon footprint and do not shift to sustainable production, we aren’t going to be able to sell our wines,” she said.

But Chile is facing a predicament that is beyond the control of any exporter: A considerable proportion of the country’s energy sources are heavy contaminants. About 18 percent of the country’s energy comes from oil and about 9 percent from coal, and those numbers are only trending upward. From 2000 to 2010, the use of geothermal energy rose about 15 percent, at the expense of hydroelectricity.

Moreover, a controversial thermoelectric plant project, now in the last stages of environmental assessment, will practically double the amount of coal-based energy in the future. The coal- and petcoke-based Castilla plant to be built about 500 miles north of the capital will supply energy to two-thirds of the country, right through wine-producing lands, weighing on the carbon footprint of every bottle produced.

“It’s easy to talk about diversifying energy sources, but renewable energies are expensive. So the country has to decide: Do we want to produce with a lower carbon footprint or do we want products that are more price-competitive?” asked Rodrigo Valenzuela, who consults for nearly 10 Chilean vineyards and works for the consulting firm Deuman, which specializes in climate change and energy.

Major supermarkets and retail stores around the world, such as Tesco in the U.K., Casino in France and Wal-Mart in the United States, are already using voluntary carbon-labeling schemes, pressuring suppliers to adopt more sustainable production practices.

“Wal-Mart is saying that if their suppliers are not sustainable, they won’t place their products on their shelves. Wal-Mart has pledged to diminish its emissions and to achieve it, has to make its suppliers do the same,” said Lapostol.

Chilean wine producers know they need to invest more, and “Innovate or Die” seems to be their motto.

“We need to be proactive and not wait for these regulations to be mandatory and turn into market barriers,” said Juan Somavia, managing director of Wines of Chile, an industry association representing about 95 percent of producers. “When these demands come into effect, we are going to be prepared.” Copyright 2010 GlobalPost. To see more, visit .