All staff at the paper merchant were invited to take part in the WWF's Earth Hour.

Veronica Heaven, corporate responsibility director at PaperCo, said: "Saving energy is one of our key goals. We have ambitious targets to cut CO2 emissions by almost 30% against the company's benchmark 2007 figure."

In 2007, PaperCo's CO2 emissions were 14,791 tonnes per annum, and the group has said it is committed to lowering that figure to 10,410 tonnes by 2020.

According to Heaven, the company had focused on its company car policy over the past year, encouraging the use of hybrid and lower CO2 emission vehicles.

DeliveryCo, the UK logistics arm for PaperCo's parent Paperlinx, introduced teardrop shaped vehicles in March in order to reduce its carbon output.

Earth Hour is organised by WWF and has almost 5m supporters in more than 100 countries.