UCL is proud to say that all of ISD’s laptops, desktops and monitors are EPEAT Gold rated.
What is EPEAT?

Electronic waste is the fastest-growing waste stream in the UK, according to the Department for Environment, Food and Rural Affairs (Defra). Ten million tons of electronic products will be bought in the UK in the next six years alone. This amount will include 20 tons of gold, 400 tons of silver and seven tons of platinum-group metals – worth some £1.5bn!
UCL's hardware

Therefore UCL is getting maximum value from them, and helping reduce the impacts of otherwise mining for metals for new hardware.
That doesn’t mean you are excused from forgetting to switch your machine off though!