How do I figure out what size generator I need for my home. I am counting my circuit brakers and fuses they are all adding up to a total of 550 amps between all of them. What size generator would I need to purchase to power my whole house. What is the conversion between amps and watts.

You need to contact one of the bigger companies that have whole house generators. They are expensive and will custom do a system for your home. And will hook it up properly so as not to fry your home wiring when it kicks on.

There are calculators available online, however, the best solution is to contact an expert for powering your whole house, as twinkiedooter says. Most people buy the smaller load generators to keep some lights and essential appliances running during outages.

Trying to sustain the power needs for your whole house is very different and demands more professional design and equipment.

To answer you calculation question, (not taking into account motor load times, peak power calculation, and other factors):

550 ampres single phase / 120 volts at a power factor of 1.0 = 66k kWh (66,000) - reactive load (amps x volts x load factor)

Adding the amp ratings of circuit breakers in a panel is an irrelevant value. Means absolutely nothing.


P=EI, or watts equals volts time amps
Amps = Watts divided by volts.

A 1000 watt toaster at 120 volts is 8.3 amps

One of many on line calculators to size generators:

https://www.ch.cutler-hammer.com/generatorCalc/wattshow.jsp

Best to contact a dealer to assist with sizing and installing the unit properly, with an automatic transfer switch to intercept the incoming utility service. Size will depend on the existing connected load and what exactly you will need to run at one time.

Cliff, please stay with admin tasks, as this is not a valid calculation:

550 ampres single phase / 120 volts at a power factor of 1.0 = 66k kWh (66,000) - reactive load (amps x volts x load factor)

You may want to consider deleting it, and editing my reference, as it illustrates a level of inexperience with electrical calculations.

Great (and relevant to my needs) thread!

I'm wondering about propane vs. diesel.. I don't want to meddle with the fuel tank to keep the gas stable when it's not getting used?

Do you have Ng available? Works great and much cheaper than both diesel or propane.