Renewable CO 2 recycling and synthetic fuel production in a marine environment

Significance Humankind must cease CO 2 emissions from fossil fuel burning if dangerous climate change is to be avoided. However, liquid carbon-based energy carriers are often without practical alternatives for vital mobility applications. The recycling of atmospheric CO 2 into synthetic fuels, using renewable energy, offers an energy concept with no net CO 2 emission. We propose to implement, on a large scale, marine-based artificial islands, on which solar or wind energy powers the production of hydrogen and the extraction of CO 2 from seawater and where these gases are catalytically reacted to yield liquid methanol fuel. The present work proposes specifications for such facilities and highlights essential challenges in physics, chemistry, and engineering which must be met to realize this ambitious proposal.