Is the proliferation of edge data centres counterproductive towards the goal of more sustainable software?

Proponents of edge computing (myself included) have argued that the edge can help us create more environmentally friendly software. While removing the use of a data centre for some operations by running them locally rather than on a remote server is a clear step in the right direction, what's less obvious is the use of edge data centres (EDCs).

On the surface, the addition and use of large numbers of EDCs globally don't appear to be contributing towards a reduced carbon footprint. So why would we argue that it's a 'greener' option?

There's a major characteristic to highlight where EDCs differ from AZs and that's that EDCs can be incorporated into existing infrastructure in cities and towns.

An example of this is what Walmart and FedEx did by repurposing their stores and warehouses to house data centres to enable edge computing capabilities.

Because they can be incorporated into existing infrastructure, opportunities exist to leverage the data centre in other ways. One example is to use the heat emitted from the EDCs to heat buildings.

This would have a significant impact on energy consumption, particularly in places that experience cooler temperatures. The International Energy Agency puts the energy consumed by the operations of buildings (cooling, heating, lighting, etc.) at 26% of global energy-related emissions with heating accounting for half of that energy demand.

The combination of reduced emissions related to the handling of the request that using the edge provides as well as a reduction in emissions through the reuse of the emitted heat from the EDCs means that the use of EDCs can be a much more environmentally friendly option compared to the sole use of AZ data centres in our software.