India, Sept. 21 -- 376.4 billion. That's how many emails we're sending every day, in 2025, according to a recent study by technology market research company Radicati. If that seems high, just scroll through the junk mail and newsletters in the rarely accessed folders of your inbox. Every email has a complex carbon footprint. There is the energy use on the client device: the personal phone, PC or tablet. The energy required for transmission: via ethernet, wifi or mobile networks. And there's everything that happens at the data centres, where servers process each message. This involves storage, checking for spam, relays from the sender's server to that of the recipient. Energy is consumed when the message is read too. Add to that the energy i...