Pros / It has a very efficient engine with a long running time.

Cons / The surge wattage is only 1,000 watts more than the running wattage.

 Verdict / The Yamaha EF series has some of the most reliable and efficient portable generators available for everyday and emergency use.

Many portable generators are cheaply made and unreliable – generators that provide power in a pinch but don't stand up to everyday usage. The Yamaha EF series of portable generators is not that type of generator. The fuel-efficient and reliable Yamaha motor combine with comprehensive safety and control panel features to make a generator that can handle an emergency power outage as well as powering a construction site. For these reasons, it easily earns the Top Ten Reviews Silver Award for best portable generator.

Yamaha EF5500DE Visit Site
  • Surge Wattage Increase
  • Fuel Efficiency
  • Running Time
  • Fuel Tank Capacity
  • Weight
  1. The increase of power that the generator can produce for short periods.
    Watts (Higher is Better)
  2. 2  Yamaha
    1000.0 Watts
  3. 1  Honda
    2000.0 Watts
  4. 1500.0 Watts
  5. Category Average
    1225.0 Watts

Power & Fuel Performance

Yamaha's EF series has portable generators that range from 1,000 running watts, which is good for camping, to 12,000 running watts, which is ideal for industrial construction sites where many heavy-duty power tools are used. Since 5,000-watt generators are the most common power range for families that need to power essential appliances during an emergency, we reviewed the Yamaha EF5500DE portable generator.

One of the best features of this gas generator is the efficient engine, which is essential in an emergency because gasoline can be difficult to acquire during a power outage or natural disaster. It can run for nine hours with a full load and 12 hours with a half load. The automatic idle allows the engine to wind down when power isn't being used, saving fuel and making it even more efficient when you're running different loads throughout the day.

A flaw with the EF5500DE is the low surge power rating. The running power is 4,500 watts, but it can only handle an extra 1,000 watts for surges, which occur when appliances with electric motors start up. Electric motors often require two to four times as much wattage at startup as when they're operating. For example, a 500-watt appliance could require 1,000 to 2,000 watts at startup. For comparison, the best portable generator has a surge increase of 2,000 watts. The average surge increase is 1,250 watts.

Safety Features

The best safety feature is the ground-fault circuit interrupter (GFCI) protection for the outlets. All the best generators have circuit breakers to protect the generator and your appliances from overloads, but few also have GFCI protection. GFCI is a type of circuit breaker that measures the alternating current going back and forth between the generator and the powered appliances. If the returning current diminishes, then that means the current has found an alternate path to the earth, which puts you at risk for electrocution. When this occurs, the GFCI shuts off the power.

Another good safety feature is the low-oil shutdown – a sensor that shuts down the engine when the oil levels are too low. It's important because it saves the generator from damage, so you'll still have a reliable source of power during an outage.

The operating noise is 74.1dB, which is average. It's not overwhelmingly loud, but it's also not so quiet that you can carry conversations near it. For comparison, the best gas generators operate at 71dB, which is about the volume of a vacuum. The inverter generators in the Yamaha EF series are much quieter, but that convenience comes at a much higher price. Also, the muffler is equipped with a spark arrestor to catch any sparks exiting the engine. This is a requirement if you want to use it while camping in national parks and most state parks, where forest fires are always a concern.

Control Panel Features

The Yamaha EF5500DE has comprehensive control panel features. Like most portable generators, it has four household outlets, but it also has two 120/240-volt outlets, though only one is a twist-locking outlet – an outlet that locks the plug in place so that it doesn't disconnect from the generator from vibrations or movement. Unlike most portable generators, it has a voltage selector switch that allows you to isolate the required voltage for your use. For example, if you're only using the household outlets, you can switch the generator to 120 volts only. This produces a more accurate electrical current that's less likely to damage your appliances.

It also has an electric push-button ignition, a fuel gauge, a digital voltage meter and an hours meter. The hours meter keeps track of the hours spent in operation, much like the odometer in your car, helping you gauge when the generator needs servicing.

Help & Support

Each Yamaha EF generator comes with a three-year warranty. You can also get excellent help through phone and email. In case you want to learn all the ways you can use your generator, there are videos, maintenance tutorials and product manual downloads. The only missing support feature is a FAQs page. Yamaha also has an extensive network of service centers and dealers capable of servicing your generator.


The Yamaha EF5500DE generator is among the best portable generators because it provides efficient and reliable power to your essential appliances. With a running time of 12 hours, it burns fuel very efficiently while also producing clean power, even though the additional surge power is less than that of most generators.

Yamaha EF5500DE Visit Site

Specifications and Benchmarks

Power Ratings

Rated Watts
Surge Watts

Power & Fuel Performance

Fuel Type
Surge Wattage Increase
Fuel Efficiency (gallons per hour)
Running Time (hours)
Fuel Capacity (gallons)
Engine Displacement (cc)
Automatic Idle

Safety Features

Ground-Fault Circuit Interruption
Low Oil Shutdown
Spark Arrestor
Never-Flat Tires
Automatic Voltage Regulator
Ground Terminal or Neutral Bonded
Outlet Circuit Breakers
Operating Noise (dB)
Weight (lb)

Control Panel Features

Household Outlets (120 volt AC)
Industrial Locking Outlets (120/240 volt AC)
Electric Ignition
Fuel Gauge
Voltage Selector Switch
Voltage and Hours Meter

Help & Support

3 Years
Phone Support
Email Support
Service Center Network
Maintenance Tutorials