A Canadian company called Pond Biofuels is capturing CO2 emissions from a cement plant in algae — algae the company ultimately plans on using to make biofuel.

It’s no secret that the process of manufacturing cement is both energy intensive and dirty. Global cement production alone emits roughly five percent of greenhouse gas emissions annually, both as a byproduct of limestone decarbonation (60%) and from the burning of fossil fuels in the cement kilns (40%). And as the demand for concrete-intensive infrastructure soars in developing countries like China and India, global emissions from cement plants–and other industrial sources–will continue to rise.

But a Canadian company called Pond Biofuels sees some real opportunity in all those industrial greenhouse gas emissions. At the St. Marys Cement plant in southwestern Ontario, Pond Biofuels has become the first to successfully use carbon dioxide emitted from a major industrial source to produce high value biomass from microalgae.