Do transformers generate ELF waves?
1) Are transformers generators? NO.

2) Do transformers radiate E/M waves? Generally, transformers are very poor at radiating E/M waves.

3) Do transforms have an E/M near field? Typically transformers have a very small near-field considering the amount of power they transform. All transformers are designed to have a very small near-field because it would be ineffecient: field outside the transformer coils is field that is not being used.

4) Is there a detectible near-field? Yes, if you have the correct equipment.

5) Is there a detectible radiated field? No, not unless you are doing something weird.

6) Is the near-field or the radiated field as detectable as that from a HV transmission line? No, normally not.