While world leaders held a virtual climate emergency summit this past spring, members of another important international group were also busy reckoning with greenhouse gas emissions: beer manufacturers.

Heineken’s CEO announced the company’s commitment to achieve full carbon neutrality by 2040. Colorado craft beer maker New Belgium Brewing made a point by releasing a “specialty beer” brewed from smoke-tainted water, weedy dandelions and other ingredients one might find in an overheated dystopian future. As this ancient and massive industry scrambles to get greener fast, one possibility gaining ground is reducing the drink’s carbon footprint by temporarily removing much of its water—which makes up 90 to 95 percent of most beers.

In addition to farming and refrigeration, a lot of beer-related emissions result from hauling kegs and other bulky containers to market via the existing, not-so-green infrastructure. “We can’t go out there and change what transportation looks like,” says Katie Wallace, New Belgium’s director of social and environmental impact. So beer makers are exploring creative new packaging technologies to reduce shipping needs. One possibility involves concentrating the beverage.

A Colorado-based company called Sustainable Beverage Technologies (SBT) has developed BrewVo, a machine that produces a version of beer containing far less water than usual. The system uses what SBT calls a “nested fermentation” process to make this concentrate. First, it brews a standard beer. The machine then removes the alcohol and finally adds a new batch of wort (the sugary liquid extracted from grain mash) so additional fermentation can take place. This process is repeated several times, yielding a viscous concentrate that the company says is much more aromatic than a fully hydrated beverage. This concentrate and the removed alcohol can then be stored in separate bags and placed into recyclable boxes for shipping. After transportation, the alcohol is mixed back into the concentrate (or left out in the case of nonalcoholic beer), and the beer is rehydrated and carbonated before bottling or serving.

SBT says its bags can travel at one sixth the weight and volume of filled bottles, cans or kegs, eliminating much of the greenhouse gas emissions associated with packaging, shipping and refrigeration. The boxed concentrates also fit into a shipping container more efficiently because they have better pallet density than traditional cylindrical containers (which unavoidably have empty space between them). According to SBT’s founder and chief technology officer Pat Tatera, concentrates thus travel eight times more efficiently than kegs. SBT also claims its beer concentrates can be frozen to extend their shelf life, reducing waste.

Meanwhile the Revos beer- and beverage-concentration machine (designed at the Massachusetts Institute of Technology and manufactured by Swedish company Alfa Laval) uses reverse osmosis to concentrate already brewed beer, as well as wine or cider. This technique has long been used to filter out contaminants by forcing liquid through a membrane with extremely tiny pores. But in the Revos machine, the high-pressure, low-temperature process removes water from beer while leaving alcohol, flavors and aromas in the remaining concentrate. Its inventor, engineer and businessman Ronan McGovern, says such concentrates are approximately five times more efficient to transport.

Once a beer concentrate reaches its destination, it requires another specially designed machine to prepare it for consumption. SBT and Alfa Laval each sell their own proprietary tap systems that add filtered water and recarbonate the beverage. SBT’s system can adjust each individual drink’s alcohol by volume—this gives bar patrons more control over the amount of alcohol they consume over the course of an evening even if they down multiple pints. The concentrates can also be blended and finished, then stored in kegs, bottles or cans.

Though the idea of beer concentrates might sound startling to connoisseurs, a similar process has long been used to transport soda in syrup form. But beer is of course a more complex beverage with a lot of culture tied to it, from specialty magazines to major international competitions. So brewers have to prove that beers made from concentrates can taste as good as standard ones. To get started on this, nonalcoholic beer brewed with BrewVo technology was entered into the 2019 Best of Craft Beer Awards competition. Pitted against well-regarded session IPAs, the beer won gold—beating out entries from some established craft breweries. And Deschutes Brewery’s nonalcoholic Irish Style Dark, also produced using a BrewVo machine, recently won bronze at the Australian International Beer Competition. Both winning entries had been turned into concentrates through BrewVo’s technology before being blended, finished and served to judges.

“The beers that they’re putting out are the best I’ve tasted,” says Steve Indrehus, who owns the Colorado-based Tommyknocker Brewery and is using BrewVo to craft both full-strength and nonalcoholic versions of some of his products under a separate label.

Although competition results indicate BrewVo can produce quality nonalcoholic beer, the next hurdle is to show the removed alcohol can be mixed back in to consistently put out equally-appealing full-strength brews. Indrehus may be making full-strength beer with BrewVo, but some other brewers have only used it for their nonalcoholic products. Their hesitation could arise from worries that adding different quantities of alcohol will change a beer’s taste in unexpected ways. Or it could simply be because the beer-industry is notoriously slow to adopt innovations (for instance, it took craft brewers decades to start choosing cans over bottles even though the former is widely considered to be better for preserving beer).

Beer concentrators are now available to commercial producers. SBT is letting breweries use BrewVo machines at its Colorado location, and the company plans to eventually build and sell them for customers to purchase and keep on-site. And Revos machines became available for sale this summer. McGovern and SBT’s CEO Gary Tickle both estimate one- to three-year break-even points for breweries purchasing these devices. SBT and Alfa Laval suggest breweries will gain back their initial outlays through reduced shipping costs, and not having to own, wash or transport empty kegs.

These economic incentives do not always translate to obvious environmental benefits, however. For example, one BrewVo customer is based in the Pacific Northwest. Once that brewery receives its bagged concentrates from Colorado, it blends and cans its beer in its West Coast facility before shipping the now fully hydrated beverage to the East Coast. To avoid such situations, McGovern says, “we’ll need to work with the brewers to help them along the supply chain.”

Of course, there are other ways to make the transportation process more sustainable. Initiatives such as Conscious Container in Northern California and the Oregon Beverage Recycling Cooperative aim to establish systems that ensure glass bottles will actually get reused—instead of ending up in landfills, as nearly two thirds of glass products currently do. According to Caren McNamara, founder of Conscious Container, packaging, which contributes to more than a third of beer’s emissions, “is the last mile when it comes to sustainability.” Beer concentrators should be able to at least help address part of that problem.