The London School Of Economics and Political Science (LSE) has become the first UK university to be independently verified as carbon neutral.
The university has reduced direct emissions by 44% since 2005 following a £4.8m investment in energy efficiency.
To gain carbon-neutral PAS 2060 status for the year 2020-21 the university also funded 80,090 sq m of rainforest to offset carbon emissions.
A spokesman said LSE hoped to be "an inspiration for others".
Prof Nicholas Stern, chair of LSE's climate change and the environment institute, said: "Higher education institutions have a duty to show leadership and advocate for decisive action in tackling climate change, the challenge of our times."
The university's carbon-neutral status was verified by the British Standards Institution (BSI). The LSE now has PAS 2060 status, a carbon-neutrality certification created by the government, for the academic year 2020-21.
LSE began updating campus and residential buildings in 2015. Solar panels, pipe insulation and LED lights were fitted, while more energy-efficient boilers and chillers were installed.
The university has procured all the electricity it uses from 100% renewable sources such as solar and wind since 2009.
About a third of the university's carbon emissions have been offset through funding 176,200 trees in rainforest across three continents.
The carbon offset is the equivalent of 20 million kilometres driven in a petrol vehicle, according to the Compensate Foundation, LSE's partner in carbon-reduction projects.
The university is working to become net-zero carbon by 2030.