(In a related estimate, 0.0003 kWh/search means 54 CPU-core-seconds of indexing per search, assuming (without any justification and probably wrongly) that (i) m

(In a related estimate, 0.0003 kWh/search means 54 CPU-core-seconds of indexing per search, assuming (without any justification and probably wrongly) that (i) most electricity consumption is by CPUs during indexing and (ii) they are using x86 machines with about 20W/core power consumption. I'm sure someone else here can fix/improve this estimate.)