From a science pov it makes sense that it’s something to pursue, even as just a renewable biofuel. Algae grows fast, it’s where oil comes from, it’s a biological “fix”. It’s perfect. Except it didn’t work nearly as well as hoped.

I looked into it a long time ago as a “solution” to how to best pull carbon of out the air and sequester it. Algae farms over deep water areas, grown and culled and the dead carbon sunk deep to stay out of the loop. Sounds perfect, doesn’t it?

But in both scenarios there are so many costs and variables to consider that are left out when proponents are selling it. Some are just the “forgotten” costs of running a process that pollutes on their own and take energy (that requires emissions too). Some are effects outside the process that damage the environment in other ways. And the costs and effects of feeding the algae itself, it just won’t grow in a vat of water alone. So many things that change the net result. And with the case for fuel (which doesn’t lock the carbon away so it’s not a help to existing carbon in the air) assuming the fuel percentage per weight would be high enough to justify the rest of the costs. Which Exxon figured out it was not, while selling it as a miracle.