Two, it had to be a technology that was scalable, that it could deliver the same benefits on the same timetable as fossil fuels, so that they can enjoy the kind of life, again, that we take for granted.
Och som nummer två måste tekniken vara uppskalningsbar, så den kunde ge samma nytta under samma tidsrymd som fossilbränslen, så de kan njuta av livsstilen som vi tar för given.