Direct air capture is the holy grail of climate solutions. Its success would offer us a way to put the cat back in the bag, and see CO2 levels decrease. The pr

Direct air capture is the holy grail of climate solutions. Its success would offer us a way to put the cat back in the bag, and see CO2 levels decrease. The problem is how absurdly expensive these things are. In the next couple decades, even being optimistic, it's hard to forsee a scenario where we've plugged enough holes in our infrastructure that direct air capture will be better or cheaper than doing more capture inside some existing pollution site, or replacing more fossil fuels with clean energy. But one day we will reach that point. And when we reach that point, anything to reduce the cost of carbon capture a little bit will help a lot. So yes, regenerative breaking connection is sort of a distraction. But improvements to DAC efficiency are very welcome, and improving airflow by mounting the mechanism on a high-speed train seems like it offers a big improvement.