How Does a Backup Generator Work?

If you own or operate a retail, commercial, or industrial facility, unexpected power outages are probably something you simply can't afford. While certain parts of the country may be less likely to experience power outages due to natural disasters, no power grid can guarantee 100% uptime. In order to keep the lights on, no matter what it may look like outside, buildings rely on backup generators to provide power when the local grid can't.

Investing in a backup generator can be a big step for some building owners due to technical complexity, the number of choices, and of course, the upfront costs. Keep reading to learn more about how backup generators work and what type of generator might work best for your property.

Generator in urban rooftop garden

What is a Backup Generator?

An emergency backup generator is a static structure connected to the main electrical system. It acts as a backup power solution that provides power to a building in the event of a power outage. These backup systems are intended to provide power for days during long stretches of power loss.

They come in an array of options, allowing a perfect fit for any building type need.

How Does a Backup Generator Work?

Generators work by converting mechanical and chemical energy into electricity. The combustion of fuels gets the motor going, then electrons from this motion are captured and forced through an electrical circuit. Once an established current is channeled through a copper wire, it’s used to power external devices.

Some systems require a manual power transfer, but many have an automatic transfer switching (ATS) system. In an automated system, these components ensure that a building can maintain constant electrical power during an outage.

An ATS is an electrical switch that helps the generator switch from one power source to another. For example, from city power to the backup generator system. When there’s a power outage, an automatic transfer switch engages within seconds to kick on the standby generator to provide an almost seamless power transfer. When the power grid kicks back on, the ATS will switch the generator off and revert the building back to the main power supply.

Having these generator systems professionally installed is the best way to protect against unexpected blackouts.

Types of Generators

Generators have different fuel sources, functions, uses, and load capacities. There isn’t a one-size-fits-all generator that meets the need of every building type. With a large variety of options, there’s a generator for any building type.

Diesel Generators

Diesel generators are one of the most common options on the market. Because diesel fuel is less explosive and flammable than gasoline, it can be stored on-site. Its lower burn temperature gives diesel generators a longer lifespan than their counterparts that run on more combustible fuels.

One of the most significant drawbacks of a diesel generator is that it is a high-emission fuel, which releases a lot of carbon and other particles into the atmosphere. With global warming being a growing concern, many municipalities have fuel ordinances in place. Check your city’s emissions regulations before investing in a diesel generator.

Natural Gas Generators

Natural gas is a highly efficient and clean-burning fuel that is piped in through city utilities. If you’re lucky enough to have a gas line, you can run a natural gas generator indefinitely without needing to refuel.

On the other hand, natural gas generators require maintenance more often than other generator options. Because natural gas is highly combustible, utility companies first shut down gas lines during natural disasters to prevent explosions. Natural gas generators aren’t viable if you live in an area highly susceptible to extreme natural disasters such as hurricanes, tornadoes, or earthquakes.

Propane Generators

Propane generators are a sought-after option due to propane having a long shelf life, and it also has little to no emissions, making it a great green alternative.

However, propane is highly combustible and more expensive than other fuel sources. Propane generators are much more complex, requiring professional repairs and high maintenance costs.

Dual Fuel Generators

Dual fuel generators are bi-fuel capable and can run on two different fuels. For example, many can use both gasoline and diesel. These generators are a great option if you want to optimize your backup generator abilities, allowing you to reap the benefits of two backup systems.

Parts of a Generator

Backup generators are complex systems that require professional installation, repairs, maintenance, and upgrades. They are comprised of several moving parts that all work together to provide an alternative method of powering a building. The main parts of a generator include:


The engine supplies energy to the generator, and its size determines the electrical output capacity. The engine’s motion is powered by combusting fuel, creating mechanical energy, which is then converted by the alternator and channeled via copper wires.


The alternator converts mechanical energy to electrical energy by creating an electromagnetic field that controls the movement of electrons. Their movement is what generates electricity.

Fuel System

The fuel system is like the digestive system of the generator. It includes a fuel tank, a fuel pump, a pipe that connects the tank to the engine, an injector that forces the fuel into the combustion chamber, and a return pipe. The fuel is filtered to remove debris before reaching the engine.

The Voltage Regulator

The voltage regulator is used to automatically regulate voltage, meaning it will convert fluctuating voltage levels into constant voltage levels. It can also convert the electrical current from AC to DC if necessary.

Cooling and Exhaust Systems

As energy is converted from chemical to electrical, some of it is lost as heat and exhaust. The cooling system ensures the engine doesn’t overheat, and the exhaust system exhales waste products.

Lubrication System

Like with any engine, there are many small moving parts within a generator, and they need a lubrication system to keep them moving smoothly and prevent them from grinding against one another and wearing down. A generator’s engine oil should be checked at least every eight hours during operation.

Battery Charger

A battery is what starts up the generator. The battery charger is an automatic component that supplies the battery with a constant low voltage level, so it can turn on when needed.

Control Panel

A generator control panel is a visual display that presents the different details and parameters regarding the generator while the generator is running. These include current, voltage, and frequency. The control panel is where you can access every aspect of generator operation.


The frame gives the generator structure. It’s the main body of the generator that holds all these key components together.

The Importance of Commercial Generators

If you feel like there are more blackouts than ever these days, you’re actually right. Blackouts caused by natural disasters have more than doubled since 2000, and these unpredictable events show no sign of slowing down.

There are wildfires and rolling blackouts every summer in California, winter snow storms that cripple places like Texas that aren’t used to such extreme weather, and hurricanes and flooding are also on the rise.


Investing in a commercial backup generator protects assets and can prevent injury and even death.

Safety During Blackouts

Without electricity, HVAC systems and building automated systems can’t function and remove the ability for people to stay warm or cool down. This lack of temperature control can result in hypothermia, heat stroke, or even death.

A backup generator allows critical systems to remain functioning even when the rest of the building is without power.

Allows for Work to Continue

Without a backup generator, blackouts are catastrophic to productivity. Power outages can mean a total shutdown in operations – factories can’t produce, retailers can’t make sales, and data can’t be accessed without a server connection.

Backup generators allow work to continue and critical files to be saved even when the utility grid is compromised unexpectedly.

Product Protection

Backup generators also prevent the loss of assets. Depending on the length of time the power is out, businesses like grocery stores or restaurants that require refrigeration could lose their perishable goods within a matter of hours without a backup generator.

Not only is food a significant concern during blackouts, but companies also run the risk of losing vital documents and data if servers shut down unexpectedly. Because commercial backup generators kick on immediately, there’s no service interruption, and processes can continue as usual without any losses.

Talk To The Pros At Suncoast Power About Your Backup Generator Needs

If you’re still not sure if investing in a backup generator is the right choice, our team is here to answer any additional questions you may have. Suncoast Power has provided commercial electrical services such as backup generator installation, emergency backup system design, and even solar panel installation in South Florida for over 30 years. Our team has the experience and expertise to get the job done right the first time.

Give us a call today at 754-200-5872 to speak with a member of our team. Our representatives are standing by to answer any questions you may have and get your site visit booked.