The absolute most efficient light source is the deep yellow/orange Low Pressure Sodium. HPS and Halide come next (one is a bit better than the other, I forget which) and flourescent last.
But:
Low pressure sodium is highly monochromatic. Everything looks kinda like the Torch Reviews site, ie, orange and brown
, no other colours to speak of. And it can take 8-9 minutes to run up.
High pressure sodium does better on the colour side and the run-up side, but it is still predominantly orange ("Golden White") and takes about 4-5 minutes to run up.
Halide lighting runs up in a similar time to high pressure sodium. The colour can be pretty good, usually a colder white but some are avaliable in warmer tones. It is the most expensive, or at least, used to be.
Hot cathode flourescent lighting can be obtained in almost any colour-temperature including pure daylight white, runs up virtually in seconds (though can take a minute or 2 to hit its peak) and is the cheapest and most avaliable of them all.
So, it`s up to you. The deciding factor would be whether you need instant illumination or not. If you do, you have no choice. If not, then decide whether you need full colour rendering or just to be able to see where stuff is.