On Thursday, Amazon announced that it would be making a program widely available to Amazon Prime members that would allow them to schedule all deliveries for a single day, once a week. The so-called "Amazon Day" service will be voluntary and targets customers who are concerned about their carbon footprint.

Grouping purchase deliveries will help Amazon cut down on emissions associated with sending a delivery truck to the same house multiple times a week, and the company says holding orders for a single day during the week will also allow it to group orders within a single package, thereby reducing packaging. Customers can select their preferred day of the week to receive shipments. According to CNN , customers can add items to their Amazon Day shipment up until two days in advance of the shipment.

Customers can also choose to remove an item from "Amazon Day" delivery, having it shipped more expeditiously if necessary. Select Prime members have already had access to the program, but it was made available to all Prime members as of today.

Maria Renz, vice president of delivery experience at Amazon, said in a statement that the Amazon Day pilot program "has already reduced packaging by tens of thousands of boxes."

The program is part of Amazon's plan to get 50 percent of its shipments to net-zero carbon emissions by 2030. The company has recently led a $700 million investment round for a company called Rivian, which promises to make an electric pickup truck and van by late 2020. In late 2017, Amazon tested out hydrogen fuel cell forklifts in its warehouses, as well.

Previous studies suggest that Amazon may have good luck getting Prime members to select Amazon Day. A 2016 paper using data from Amazon Prime showed that customers were likely to select slower shipping if Amazon offered to buy carbon offsets in lieu of two-day shipping.