The bad news is the transformers used everyday to step down voltage from some high voltage I.E. 14500 to 240/120 work backward. some poor lineman, working in bad weather can get his last surprise. Have it installed by a competent electrician. Don't jury rig. I once did. I was in the sugar house, generator power failed briefly, utility power came on. A friend not knowing the sequence came along and wanted to be helpful. Nobody got hurt, but that was luck not good decisions.
As to voltage and frequency, we routinely save energy with inverter motor drives, or frequency drives. These convert single or three phase to DC single phase then convert it back to three phase at any voltage or frequency we choose. There is engineering involved. Then it is monitored to avoid heating, over speed, under speed, and stalling. Most motors are meant to run at a speed determined by frequency, the number of poles. Synchronous speed for a 60 cycle two pole motor would be 3600 RPM, A 4 pole 1800. At no load they will run close to this speed. At full load you will see considerable slip, hence the nameplate common of 1750 or 3450. Varying frequency wouldn't harm a motor at no load, does speeding it up mean more torque load? Will it slow it down and not produce enough torque to do the job. Any energy sent to a motor must do work or produce heat. I would strive to maintain design voltage and frequency
The above described warnings sould be heeded. The comments concerning energy savings are worth note. There has been a move toward load design engineering efficency as opposed to capacitor bank load switching to balance total plant load for efficiency. For more insight you may want to research reactive AC "tank circuit" explainations. Avoid the claims about perpetual energy conversation concerning tank circuits unless it is described as theoretical.
Tesla researched and found that 60Hz, 240VAC worked best from an electro-mechanical/efficiency perspective from what I have been told. I can only suggest that this has something to do with the natural emf generated by our planet being, basically, a massive generator and its basic frequency and a compromise voltage. I am certain that statement will generate additional comment/arguement.
However, for us who only want to power our homes for a short period of time during crisis, we have to remember a few things.
1. Electric lights are not necessary. You can easily have any sort of oil, gas, or wax lamp. Electric lights, if deemed necessary, do not care too much about voltage levels or voltage frequency.
2. Water is essentual - it does not have to be "pure" but you don't want it to make you sick. If you have a well, you want to power the pump if it is electric.
3. Refrigeration is only necessary if it is hot outside and you have stores of perishable food. You can live on canned food. Canned food manufacturers have best use dates on their goods. This is not, necessarily, "don't use beyond" dates. Use your brain based on the content and storage conditions.
4. You have to prepare to be able to heat your dwelling in some manner. I would suggest some manner other than electricity. Oil based heaters can be used with adequate ventilation if you do not have a fireplace and a supply of other wood based combustibles.
5. It is easier and safer to store a large quantity of #2 fuel or Kerosene than it is to store Gasoline. Therefore, it is better to have a diesel fueled generator than a gasoline generator. This was validated during Hurricane Sandy. Locals who had, or obtained, gasoline powered generators could not get gasoline to fuel them. Oil stores for long periods of time without significant degradation compared to gasoline and diesel engines are generally more tolerant of fuel quality variances.
Just my opinions.
