Dale Johnston opens the gate to his neat suburban garden on the western fringes of Newport in South Wales. There’s a trampoline and a slide on the lawn for his grandchildren, and chairs for him and his wife. He should be enjoying the light draining from the perfect autumnal sky – but almost his entire view is blotted out by a vast expanse of prefabricated panels.

The 23 metre-high grey hulk looming over him and his neighbours is a hyperscale datacentre. It is heralded by the area’s Labour politicians as a job creator, yet all Johnston can think about is what he has lost: “Before, the sun used to come around here and it was lovely.” The way residents have been treated is “disgusting”.

Johnston, who used to work for a chemical company in the city, worries what their lives will be like when the centre is switched on: the 36 sets of air blast coolers, needed to stop the chips inside overheating, most likely generate a constant drone, while regular testing of 60 back-up diesel generators, to prevent costly interruption to the flow of data, could produce harmful fumes. He already has to keep his bathroom window closed to stop the low hum from another facility on the rapidly expanding 46-acre datacentre campus that borders the small enclave of 27 houses.