I cannot see a way you are going to be able to achieve an ME2 lighting class without either columns or floodlights. A low height solution is never going to be acceptable for ME2, as there will be too much glare and a relatively poor spread of light. In essence ME lighting schemes involve relatively tall columns that throw light down on the road and put objects into silhouette (a luminance class of lighting). Low level lighting is typically an illuminance class of lighting, CE, S or A.
If you want to avoid generator powered floodlights I would propose temporary columns. Obviously you would want as few columns as possible, so I would opt for 12 metre tall columns. To further improve light distribution the luminaire chosen should have a 'bowl', by which I mean a clear bowl-shaped cover beneath the lamp through which light shines and is partially refracted and spread. If I were specifying a lamp I would opt for a 250W SON-T lamp. Whilst I am not a street lighting designer, I reckon it would probably be acceptable for columns to be spaced up to 48 metres apart. The column height to road width ratio is 1:1, which is acceptable, and the column height to column spacing ratio is 1:4, which is acceptable. Depends how, ahem, particular you want to be about things.
There is then the matter of the power supply. I have seen some temporary columns fitted with an overhead power supply, whereby the power supply has been strung between the columns. The dodgy way of doing it is to just string the cable up, a better way is to fix eyelets to the columns, string a steel cable between the eyelets and securely tie the power cable to the steel cable. Doing things this way means the only excavation required would be for the column bases. Of course, there will be an element of working at height and traffic management.
If I were designing a permanent solution it wouldn't be like this, but with temporary solutions you really want to minimise numbers of columns through tall column heights, higher wattage lamps and reflector/refractor systems that spread light the best. You do not want short columns or full cut off luminaires.
The solution I have proposed would require about four columns. When a contractor installs street lighting it costs about £1500 per column nowadays, but most of this cost is in the connection to the power supply element, rather than the cost of the column. Certainly, in my opinion you would be getting ripped off if the necessary materials cost you any more than £4000, but you would have to look into costs as I am not the most familiar with them.
I hope this helps.
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