Your discussion on developments in graphene research might give the erroneous impression that we are decades away from a commercially viable method of graphene production on an industrial scale (see Nature 503, 327–329; 2013).

In fact, over the past few years the ability to grow large tracts of graphene and transfer it to multiple substrates, as well as doping, patterning and other techniques, have been developed to a point at which industrial production is progressing rapidly. You mention that the company Graphenea produces 15 square metres of graphene per year. But other companies have superior production capabilities: US-based Bluestone Global Tech, for example, has the capacity to produce 20–200 square metres of graphene per day (see go.nature.com/gja2bo).

The production cost you quote of up to US$100,000 per square metre is actually a retail price for just a few square centimetres of material. The cost of producing it is in fact much lower. Production costs have fallen rapidly in the past few months at Bluestone Global Tech, thanks to an increase in production volumes and new transfer techniques.