> why not just use that energy directly in the things that need it That's a very important point. However, sometimes you can't use the energy - like we can't

> why not just use that energy directly in the things that need it That's a very important point. However, sometimes you can't use the energy - like we can't eat CO2 + sunlight, but plants can turn that into something usable. Methanol is useful for chemical processes. The US Navy was looking into fuel production in aircraft carriers, which involved CO2 sequestration. That's useful since they have the spare power. And so on. It may also indirectly avoid more emissions - the CO2 being used has to be transported from somewhere, be it coal, oil, or other sources.