Amazon knows that the devices it sells run mostly on carbon-emitting power.

The Carbon Trust unveiled the effort last week.

So does creating devices with more efficient batteries.

They join the Echo Show 15, Fire TV Stick and Kindle Paperwhite, which already have the badge.

Still, the company found that paper was the most universally recyclable packaging currently available.

The methodology for doing this is still being developed.

The standard doesn’t take into account the carbon emissions involved in manufacturing or shipping devices.

Those are typically substantial.

Amazon is alsoworking to quantifyhow much durable devices can reduce carbon emissions.

The most Earth-friendly equipment, sustainability experts point out, is usually the one you’ve already got.