What can you power with a 7500-watt generator?
In order to determine what you can power with a 7500-watt generator, you need to find out how much wattage all of the appliances in your home use. Importantly, appliances like refrigerators and air conditioners – anything with a motor – will have two different wattage ratings: running wattage and surge wattage. Running wattage describes how many watts the appliance uses to keep running once it has already started. However, motor-driven appliances have a higher power draw when they are first starting up, which is described by the surge wattage.
You need to make sure that the sum of all the running wattages of the appliances you want to power with your 7500-watt generator is less than 7500 watts, while the sum of all the surge wattages plus the running wattages of non-motorized appliances is less than the surge wattage that your generator is rated for.
Let’s look at an example of what a 7500-watt generator can power in the standard home. A 1000-watt microwave, a standard refrigerator and freezer, and a hot water heater together use about 6,500 watts. This leaves you enough leftover power to run the lights in a few rooms as well as to power small electronics like cell phones and laptops. Note, however, that the starting wattage on a refrigerator and freezer can be quite high – over 1,000 watts in many cases – so you’ll need to make sure to plug this in first so you don’t exceed the surge wattage of your generator with all of the other appliances already drawing power from it.
Important features to consider before you buy a 7500-watt generator
There are a lot of generators that offer 7500 watts of power, particularly because this power rating is so adaptable for use in your home during a power outage or for outdoor use like in an RV. In order to help you understand what differentiates these many generators, we’ll explain some of the most important features of generators and how they can affect your buying choice.
Rated and maximum power output
Any generator on the market, regardless of its power class, will have both a rated and maximum output power. The rated power describes the amount of wattage that a generator is capable of producing consistently for as long as it is running. For all of the 7500-watt generators that we reviewed, 7500 watts is the rated power. To calculate the running power you need, simply add up the running wattages of all the different appliances that you plan to plug into the generator.
Note that for dual fuel generators like the models from Champion
, the rated and surge wattages when running on propane are lower than those when running on gasoline.
However, any appliances that have motors, such as air conditioning units, refrigerators, and freezers, will have an additional power draw when they are first started. This is where the maximum output wattage, also known as surge wattage, comes into play. Your generator will only be able to support this maximum power for a few seconds, long enough to start these appliances without stalling as the power requirement surges. If you have left yourself leeway when calculating your running power requirement, your generator will likely provide enough surge power to get all your appliances started as well.
The engine is the component of the generator that converts fuel – either gasoline or propane – into electrical energy. For this reason, the engine is truly the heart of your generator. In general, a more powerful engine will produce more power – which is why the engine sizes on most 7500-watt generators are comparable, in the vicinity of 420cc.
Fuel tank capacity
All of the generators we reviewed, with the notable exception of the dual fuel Champion and Firman generators, run only on gasoline. That means they are constructed with a built-in fuel tank to hold a reservoir of gasoline as they run, and that the size of this tank is correlated with the runtime. Fuel tank capacities are typically in the six- to seven-gallon range since this size of tank does not require a huge generator to contain, although the larger Cat generator is capable of holding nearly eight gallons of gasoline.
Note that while a larger tank will correlate with a longer runtime since the generator has more fuel to burn, runtime also depends on the fuel efficiency of the generator.
The runtime is a measurement of how long the generator can run on a single tank of fuel and depends on both the size of the fuel tank and the efficiency of the generator’s motor. Note that the generator’s efficiency depends in large part on how much wattage is being drawn from it – thus, for the same generator, the runtime will be shorter when running it at maximum capacity compared to running it with only a single appliance plugged in. In addition, for dual fuel generators like the models from Champion and Firman, runtime is typically reduced on propane compared to gasoline.
Runtimes are typically measured at half-load (i.e. half of the rated wattage) and range from eight hours on the Simpson generator to up to 11 hours on the Westinghouse and Cat generators.
The number and types of outlets on a generator are important since they can present a limit on how many and what types of appliances you can run. All of the generators that we reviewed offer at least four 12A/120V standard household outlets, and it is possible to plug a surge protector strip into these outlets to produce more outlet space. If you plan to use your generator for an RV as well as at home, look for generators like the Champion that offer RV-ready twist-lock outlets.
In addition, a 12V DC outlet can be extremely useful for charging small devices or charging batteries, which can be especially important if you are carrying your generator in an RV.
Although your generator will be outside, many generators produce enough noise to not only keep your whole house awake at night but also your neighbors. If you’re using your generator in an RV, the noise can also take away from the peacefulness of being outdoors.
Generator noise levels typically depend foremost on the size of the motor – therefore, noise levels don’t range hugely among 7500-watt generators. The Westinghouse generator is the quietest generator we reviewed at 73 dB, although the Champion generator is just behind it at 74 dB.
Size, weight, and portability
The size, weight, and portability of different generator models can matter more or less depending on where you plan to keep it and how you plan to use it. For occasional household use where the generator sits in the same place where you expect to use it, portability may be a non-issue. On the other hand, if you plan to use your generator with an RV or even for the occasional trip to a worksite, having an enormous and heavy generator can be problematic.
Generator size and weight typically vary with the output wattage and motor size, so there is not much difference in the dimensions or weight of the generators we reviewed. Many generators, including all of the 7500-watt generators we reviewed, come mounted on frames with wheels to make portability easier. However, note that these frames do add weight of their own if you expect to carry your generator up and down stairs or lift it into a truck bed frequently.
A 7500-watt generator is a significant investment, so you want to be sure that your generator will work like new for many years to come. The best way to ensure this is with a lengthy manufacturer’s warranty, which protects you if anything goes wrong with your generator. All the generators we reviewed come with a 3-year warranty.