Will a switch to light speed cut power use at data centres?

Chris Sharp, chief technology officer at Digital Reality, believes the era of copper is nearing its end. The data centre operator estimates around 400 tonnes of copper will be used in a typical 100MW facility, with most of it employed in the electrical infrastructure and cooling systems. Approximately 20 tonnes is used for connecting computer servers. To replace these wires, Sharp and many others are betting on photonics, which involves using light instead of electricity to transmit data.

Photonics, a technology that has been used for decades in long-distance communications, is now being considered for use within data centres. This innovation could potentially reduce energy consumption, as light does not generate the same heat as electricity. Researchers and companies are working on integrating optical components with electrical ones, sometimes directly on computer chips. The technology, called photonics, could provide multiple data streams in a single channel, increasing capacity.

Despite its potential benefits, photonics presents several challenges. Manufacturing and scaling up the technology is difficult due to the need to combine different engineering traditions and supply chains. Optical networking devices are more energy-efficient, but other data centre components still generate heat, creating reliability concerns for optical components. Moreover, optical networks operate at nearly the speed of light, but installing and maintaining them requires human intervention and new skills.

While optical networking is unlikely to make data centres more popular with the public, it could make them significantly less energy-hungry. Companies are still working on scaling up photonics manufacturing, and one of the advantages of this technology is that it can be produced on an industrial scale, similar to existing electronics manufacturing processes. This scalability could help lower the cost of photonics and make it more widely applicable across various industries.