Clean and green Australian universities are leading the world, a new ranking suggests. 

The Times Higher Education Impact Rankings for 2021 lists four Australian unis in the top 10 on a rating of their work towards the United Nations’ Sustainable Development Goals (SDGs).

Twenty-four Australia universities are among the top 200 globally, out of 1,240 universities rated. 

The University of Sydney has been ranked the world’s second-best in terms of sustainability, behind the University of Manchester.

RMIT University came third, La Trobe University fourth, and the University of Wollongong equal sixth with Aalborg University in Denmark.

Sydney Uni topped the class for clean water and sanitation, which is rated according to the university’s own water use and research outcomes. The university has targets of net zero carbon emissions, zero waste to landfill, and a 30 per cent reduction in potable water use by 2030. It also has 174 researchers working on clean water and sanitation projects.

The green rankings are based on the United Nations’ 17 sustainable development goals, from conservation research to energy-efficient buildings, recycling and policies on academic freedom.

Ratings were also affected by the level of financial assistance to students, gender equality, clean energy, income from patented research and plans to reduce the use of plastic on campus.

The University of Canberra was ranked number one in the category of “reduced inequalities’’, covering the percentage of students and staff with disabilities, and the number of international students from poorer countries the receive financial aid.

La Trobe University followed by the University of Sydney were recognised as world leaders in supporting the sustainability of “life on land’’, including research and direct action to protect ecosystems.

The University of Newcastle topped the table for government and international collaboration to achieve the UN’s sustainable development goals.

The University of Canberra ranked fifth, and the University of South Australia 19th, for the UN’s target of quality education. This ranking is based on the number of graduates with primary school teaching qualifications, and thow many are the first in their family to attend university.

La Trobe University ranked second worldwide for “decent work and economic growth’’, which is based on pay rates, discrimination policies and the number of staff on long-term contracts.

La Trobe ranked second for gender equality, which is measured on both research outcomes and the proportion of female graduates and women in senior staff positions.