When hot days and you need to wait for it to cool down and add ice. All those Starbucks frappucinos with this tech will save the world.

"Although the researchers say their new system could be relatively easily developed into an automatic coffee machine for home users, the biggest opportunity is likely to be for large-scale commercial producers of coffee-based drink."

They say it in the article what it is for...

Cold brew

Except cold... Why would someone drink a cold expresso? It just seems kinda gross, then again, I'm not a fan of putting cheese in my coffee either (different strokes for different folks I guess).

Perfect for iced coffee though

They're talking about commercial scale coffee products and coffee flavoured products (bottled coffee drinks, instant coffee, etc.), where a reduction of 75% of the energy consumption could not only be very profitable, but also helpful in hitting environmental targets. Coffee is already a bit of an environmental nightmare when it comes to water usage in farming, so lessening the impact of commercial coffee is definitely a plus.

You can heat the water afterwards. A lot of the heat in the hot water is lost in the beans. This might never have an application at your local coffee shop, but for canned coffee it will make a dramatic difference in profitability.

I found one for sale that does 40k that has the same form factor as the one shown in the paper. I almost want to make a high-speed coldbrew system but I don't expect it'd be worthwhile for the coffee, only maybe for the fun of building it.