Compressor jet engines work best at altitude, but you cannot get around being on the ground. Here's my numbers for fuel burn during taxi taken with a stopwatch from single-engine start to runway-hold. 10gal/min is a rule of thumb for taxi, but the carriers keep the actual numbers close to their chest. I have much more detailed information, but you get the gist of it.

FLT	Origin	Dest.	Min	sec	gal/min	total
DL1412	ATL	DTW	21	23	10	213.83
NW1730	DTW	BOS	10	30	10	105.00
DL1857	ATL	BOS	28	55	10	289.17
DL63	ATL	LAX	7	30	10	75.00
DL9010	LAX	SFO	6	0	10	60.00
DL1074	SFO	ATL	12	25	10	124.17
DL1852	ATL	BOS	32	20	10	323.33
DL1855	BOS	ATL	20	12	10	202.00
DL1516	ATL	DTW	12	40	10	126.67
NW25	DTW	NRT	30	30	10	305.00
DL500	NRT	ATL	5	15	10	52.50
DL372	ATL	BOS	10	45	10	107.50
DL1855	BOS	ATL	19	27	10	194.50