Climate Change, Sustainable Energy & Environment G20 2020 A cost-effective low-carbon framework to manage emissions from water desalination Malak Al-Nory , Mohammed Antar , Alexander Brodsky , Stephen Graves , Hussameldin Khonkar , John Lienhard , Khulood A. Rambo (MIT Effat University) , Sa'd Shannak November 23, 2020 | Last updated: December 10, 2020 Tags: Climate change and environmental sustainability The commitment undertaken by G20 countries to lower their carbon emissions levels makes renewable energy-powered water desalination especially valuable, given that almost half the global water desalination capacity is installed in these countries. Recent installations have shown that Reverse Osmosis (RO) operated by Solar PV is extremely suitable for green desalination. G20 countries should adopt Photovoltaic Reverse Osmosis (PVRO) with water storage for cost-effective and low-carbon water desalination. They should include PVRO projects within the structured financing available for renewable energy projects. The G20 countries with the largest desalination and renewable energy capacities may sign a Cooperative Framework Agreement to establish a global cooperation platform. Challenge This policy brief promotes renewable energy-powered water desalination with PVRO technology as a mechanism for creating an integrated and sustainable solution for both clean water production and energy storage. It presents the key technology, implementation, and replication-related interventions required to enable a costeffective low-carbon framework to manage emissions with water desalination. It aims to enable the G20 countries to realize higher levels of renewable energy integration in the energy mix and to realize major aspects of a circular economy. G20 countries contribute to about 48% of the total water desalination capacity in the world with about 52,264.5 mm3/day. The minimum energy required to produce this amount of fresh water using best large-scale commercial technology available today is 209,057.9 MWh/day, which will result in about 93,030.8 tons/day of CO2 emissions. The G20 can reduce total emissions by 209,057 tons/day after committing to PVRO. This can lead to an emission reduction of 428,000 tons/day globally, if other countries also learn from the experience of the G20 countries. If the G20 countries switch to water storage in place of the currently expensive energy storage mechanism as per the proposed framework, it will result in huge cost reductions (approx. 722,817 mn$) in desalination projects (See Appendix [I] for analysis and assumptions). Clean energy can power global recovery from COVID-19, especially because the pandemic hit the world’s poorest regions and the elderly (with respiratory and cardiovascular diseases and diabetes, and in countries with high levels of pollution) the hardest, and also affected the