How Do Whole House Generators Work?

While many of the products we review here are readily available to purchase and operate without a license, we always recommend hiring a qualified electrician to install and demonstrate their use.

In some cases, improper use and installation may result in a breach of insurance. Even worse, you could be putting yourself or your family at risk as an incorrectly installed electrical device could start a fire. So, don’t risk it - seek the services of a fully licensed electrician instead.

When grid power leaves you high and dry, you can count on your whole house generator to pick up the slack and keep your lights on (amongst other things), a crucial lifeline as geriatric grid infrastructure becomes flakier with each passing year.

However, with great power comes great responsibility (and price tags), so you may not be willing to just take it as a given that this fancy bit of machinery is going to swoop in, work its magic, and save the day in an emergency. 

How Do Whole House Generators Work?

We all have a very basic understanding of what these things do, but as you’ll be fully reliant on your generator to save your bacon in an emergency situation, it makes sense to learn more about how whole house generators keep your little world turning when the world at large grinds to a halt.

What Fuels Whole House Generators?

When grid power gives up the ghost and a whole house generator sparks to life and shoulders the electrical burden of a home, where exactly is it getting its energy from?

Well, portable generators rely on the user topping up their fuel reservoir with the appropriate fuel to keep them running, but you can’t just keep your whole house generator juiced in preparation for a blackout that might not arrive for months or years — It’s just not good for the generator.

What’s more, fuel expires, especially when held in a suboptimal environment such as a generator, so manually replenishing fuel isn’t really an option for standbys.

Besides, one of the main benefits of a whole house generator is that it shoulders the load immediately and automatically, and it couldn’t do so if you had to manually top it up first.

There are a couple of solutions to this problem:

  1. Natural gas lines — If you have access to natural gas lines, a professional installer can plumb your whole house generator directly into the existing infrastructure. If this is the case, you won’t have to do a thing to keep your generator running.

  1. Fuel tank installation — No natural gas lines near your property? Then you’re going to have to develop your own resources by having fuel tanks installed on your property. As these fuel reserves are finite, you’ll have to have them replenished semi-frequently.

The fuel you’ll use to power your generator depends on what your model calls for. It will either use propane, gas, or diesel (some are dual fuel designs).

How Does The Power From The Generator Reach Your Home?

So, we’ve established that a standby generator will be linked up to either a natural gas line or a fuel tank installation, thus giving it the energy to run, but how does the power it generates reach your property?

You’ll be happy to hear there are no dubious daisy chains of power strips involved.

In fact, you won’t have to make any manual connections at all, as whole house generators are wired directly into your breaker box. 

When their services are required, they get to work, produce energy, and channel it straight into the main distribution panel of your home, just as the grid would.

From there, the breaker panel does what it does best and sends power to your wall outlets so you can plug in some appliances and live a relatively normal life throughout a blackout.

How Do Whole House Generators Work?

How Does A Whole House Generator Know When It’s Needed?

The hookup to either a natural gas line or fuel tank installation keeps whole house generators primed and ready for action, but how do they know when “action” is?

This quasi-psychic power is pretty mystifying to generator novices, but it’s actually quite simple (yet genius!).

Remember, the generator is always connected to the breaker panel, and although it’s not supposed to be doing anything when there’s grid power available, it’s not exactly a completely passive installation either.

Whole house generators are fitted with sensors that constantly monitor the power levels arriving to and being distributed from the circuit panel.

When these sensors register a complete drop in power, they give the grid a few seconds’ grace to reestablish voltage.

If the power doesn’t return, something known as an automatic transfer switch fires up the generator motor, and backup power surges into the breaker panel.

How Does The Generator Itself Function?

You have a basic understanding of the motor in your car, right? And have you ever used one of those hand-cranked camping flashlights?

Well, by and large, a whole house generator combines these principles when the automatic transfers switch flips, but on a much larger scale. 

The fuel is channeled into a combustion chamber where chemical energy is converted into mechanical force via combustion.

This rotates an alternator that, in turn, spins an armature stationed between two magnets.

As the armature rotates through the magnetic field, the electrical signal oscillates between positive and negative values, producing a typical AC sine wave.

The electrical current is passed through copper wiring to the breaker box where it is distributed according to your present power needs.

Can I Install My Own Whole House Generator?

Now that you know how a whole house generator works, you might be wondering if you can handle installation yourself and save a few bucks.

While this is perfectly possible if you have some experience in the area, at the very least, you should pay a professional to come and give your work a once over, just to be sure you’re not caught out by any silly mistakes when the next outage rolls around.

If you’re not comfortable setting up fuel and electrical lines, you can still take care of basic site preparation to trim a few bucks off your installation bill.

Once complete, you can leave all the technical stuff to the professional.

Final Thoughts

If you live in an area that’s prone to power outages, investing in a whole house generator is always a wise move, and now that you know how they work, you might feel a little more comfortable doing so.

One thing we haven’t covered here is the importance of regular maintenance.

That standby generator of yours is going to be doing a lot of waiting around, and a surprising number of things can go wrong with static machinery, so to make sure it’s ready to help you out when the power goes down, be sure to carry out monthly and annual maintenance.