The article addresses some of this, though there is a difference between 1 of these and 100 of them in any space.

"The biggest environmental concern with a system like this is the heat it produces as the byproduct of computing. Microsoft researchers claim that the heat it puts out doesn’t make enough of a difference to be concerned. Results from the first phase of Project Natick showed that the heat from the pod quickly mixed with cold water and dissipated due to currents.

“The water just meters downstream of a Natick vessel would get a few thousandths of a degree warmer at most,†the researchers wrote in an article for IEEE Spectrum. “So the environmental impact would be very modest.â€

"