Picture the aftermath of a festival: A sea of fans depart, leaving behind any number of empty water bottles, disposable cups, wristbands, lost IDs and maybe even some used-up whipped cream chargers.

For all the environmental lip service we hear from megastars, the carbon footprint of live entertainment has only recently received the attention it deserves. Trash is just one piece of that puzzle, and it's currently in Live Nation's spotlight as the events giant pumps $5 million into Turn Systems.

Turn aims to help venues do away with single-use cups, and so far a series of trials show that the system is working, Live Nation claims. For venues, Turn provides reusable cups and collection bins, and operates its own dishwashers, which the company says are "700% faster than traditional dishwashers." For fans, the reusable cups don't require a deposit and are handed out by default. Once their drink's all gone, a scannable code at the bottom of the cup opens a slot at the top of a fancy, custom-branded collection bin.

Turn System's collection bin. It seems a tad slow, judging solely by this animated gif, but apparently it works. Image Credits: Turn Systems

For many folks, that's all they'll see, but as an extra return incentive, fans can also sign up via an app to be entered into giveaways for things like free merch and "VIP upgrades," said Live Nation sustainability director Lucy August-Perna in a call with TechCrunch. Behind the scenes, San Francisco-based Turn's software tracks how many cups wind up back into its system and the company shares that data with venues.

Live Nation says it trialed the tech at several events this year, including Lollapalooza, which saw a 93% return rate. It's not always so high; at the Sueños music festival in Chicago, fans returned just 58% of the cups. "We've piloted [Turn] now at several venues and across major festivals and hoped we would get the results we did," said August-Perna. Overall, "we've seen over a 90% return rate of cups," she added.