Any large industrial motor will also be three phase AC, not DC.
To run from batteries / solar panels it will need inverters to produce the AC for the pumps, rated at something higher than the motor power; the 1.8MW you mention is not unreasonable.
Even if you use batteries series up to eg. 1200V (600 cells), one set of 500AH cells would last just twenty minutes at 1.8MW load, with a discharge current of around 1500 Amps - far too high for any conventional batteries.
It would need 1,800 cells minimum for each hour of run time required & probably far more, to get the battery discharge current down to an acceptable level, if you want the batteries to have anything like a reasonable life.
The as Nigel says, fields full solar panels with an output rating of probably 8 - 12 MW or more to be able to recharge the batteries within "sunlight hours", if it's a continuously running system.