What’s the Difference Between Starting Watts vs. Running Watts?

When shopping for a portable solar generator, you'll likely come across specifications listing the unit's starting watts and running watts. These wattage ratings are important to understand, as they indicate the generator's power capabilities. But what exactly is the difference between starting watts and running watts?

In this comprehensive guide, we'll explain starting vs running watts and how they impact a solar generator's performance. By the end, you'll have a clear understanding of how to match a generator's wattage ratings to your power needs.

What Are Starting Watts?

Starting watts, sometimes called surge watts, refer to the initial power drawn by an appliance or tool when first turned on. This instantaneous surge of power occurs as the appliance starts up and gets running. Starting power demands tend to be brief but significantly higher than the appliance's normal continuous power draw.

For example, a common refrigerator may have starting watts of 1600 but run steadily at just 600 watts. The 1600 watts is only needed for a few seconds during start-up; then power needs to drop down to 600 watts.

The starting watts rating indicates the maximum power a solar generator can supply for short bursts when starting appliances. A 2000-watt solar generator can successfully start most fridges or other motor-driven appliances drawing up to 2000 watts at start-up.

Why Do the Starting Watts Matter?

You may be wondering why starting watts are so important for a solar generator. After all, the surge only lasts briefly.

If an appliance's starting watts exceed a generator's capacity, it simply won't start up. The generator won't have enough juice to get the motor going or power the initial kick needed for start-up.

For example, trying to start a 1600-watt fridge on a 1000-watt solar generator likely won't work. The 1000-watt unit doesn't have enough power output to meet that initial 1600-watt demand.

So when sizing a solar generator, it's critical to ensure the starting watts match or exceed the highest startup surge of your appliances. Otherwise, you'll have issues powering devices on the generator. Aim to give yourself a buffer between the maximum starting watts and your generator's capacity.

What Is Running Watts?

Running watts refer to the ongoing power draw of an appliance once it's up and running. For our refrigerator example, the running watts would be the steady 600 watts it pulls to run the compressor and internal circuitry.

The running watts specification indicates how much continuous power a solar generator can supply. A 1000-watt solar unit could continuously run a 600-watt fridge without issue. But running a 1600-watt appliance would overload the generator's capacity.

Running watts essentially defines the continuous power budget you have to work with on the generator. As long as appliances stay within the continuous wattage rating, they can run indefinitely. If power demands exceed the running watts, the generator will overload and likely shut down.

Running Watts in Daily Use

For most appliances, the running watts determine how much you can power at once from your solar generator.

Here are some examples to illustrate:

  • Running a CPAP machine that draws 300 watts - no problem for a 1000W generator.
  • Running a small dorm fridge that runs at 600 watts - easily doable on a 1000W unit.
  • Running a large refrigerator that runs at 1000 watts - would overload a 1000W generator.
  • Running a 300W CPAP machine and 600W fridge together - exceeds the 1000W running capacity and will overload the unit.
vtoman jump 1800 power station can run a CPAP machine

The generator's running watts constraint essentially limits you to powering smaller, individual appliances. Simultaneously running multiple high-draw devices may exceed the continuous power capacity of smaller generators. Larger solar generators above 2000 watts offer more continuous power flexibility. But running watts are still a limitation to be aware of. Doing the math on your appliance power needs versus a generator's capacity is important.

Starting Watts vs Running Watts: Key Takeaways

To recap the key differences between starting and running watts:

  • Starting watts indicate the surge power when first turning on appliances. This shows the generator's peak power capacity for brief durations.
  • Running watts indicate the continuous power output capacity once appliances are up and running. This constrains the continuous power budget you have available.
  • Starting watts must exceed appliance startup surges; otherwise, appliances won't turn on.
  • Running watts must exceed the combined continuous load you plan to run; otherwise, the generator will overload.
  • For most small generators, running watts are the main limitation for simultaneous powering of multiple appliances.

By carefully matching both wattage ratings to your expected power demands, you can size an appropriate solar generator for your needs. Keep these basics in mind while shopping and comparing specifications.

Matching a Generator to Your Appliances

Choosing the right portable solar generator for your needs requires carefully auditing the power demands of the appliances you want to run. Taking the time to make a detailed list of your expected appliance loads will pay dividends for sizing your generator appropriately.

Follow these steps to match a solar generator to your devices:

1. Create an Appliance Load List

First, make a comprehensive list of all the appliances and devices you want to power from your solar generator. This may include:

  • Refrigerator or freezer
  • Phone and laptop charging
  • Lighting such as table lamps or string lights
  • Electric cooking devices like induction cooktop or microwave
  • TV and other entertainment electronics
  • Power tools like drills, saws or sanders
  • Medical devices like CPAP machines or oxygen concentrators
  • Electric blankets or space heaters

For each appliance, you need to determine its starting and running wattages. Consult the device's user manual or online spec sheet to find these figures. If you don't have the exact numbers, look up averages for that type of appliance.

Jot down both the starting and running watts next to each device on your load list. Having these specifications is crucial for properly sizing your generator.

2.Consider Concurrent Loads

Also think about which appliances you'll need to run concurrently to determine combined power demands. For example, lights, phone charging and TV may need to operate simultaneously in an emergency.

Make notes on your load list indicating which devices will run together at the same time. This impacts the running wattage capacity required from your generator.

3.Add Up Total Wattages

With your list complete, add up the running watts for all devices that will operate concurrently. This provides your total expected power load.

As a simplified example:

  • Fridge (500 watts)
  • Phone charging (10 watts)
  • LED light (5 watts)
  • Total running watts needed = 515 watts

The combined running wattage for simultaneous operation is the minimum capacity your solar generator requires.

4.Choose a Generator with Adequate Wattages

With your expected loads defined, you can start comparing portable solar generators to find one that fits your needs. Follow these guidelines:

  • The generator's starting watts should exceed the highest startup surge of any appliance. Add some buffer if possible.
  • The running watts capacity must be greater than your expected total concurrent load. Again, allow some extra margin.
  • If you'll be powering high-draw devices together, choose a generator with more running wattage to give yourself power budget.
  • Optionally, consider sizing up to a unit with greater capacity than your current needs to allow for future expansion.

As an example, for the 515-watt load above, a 1000-watt solar generator would offer ample running watts. The 2000+ starting watts would cover appliance surges.

jump 1800 power station has strong wattage

5.Consider Physical Size and Weight

For portable generators, also factor in the physical dimensions and weight of the unit. Check whether the wattage you need comes in a size that's reasonably movable for your situations.

Prioritize matching watts first, then try to find the most appropriate physical form factor to suit your portability needs. Though with larger units, keep in mind that higher wattage often requires larger, heavier designs.

Investing in a solar generator matched to your expected loads will pay off with reliable power whenever you need it off-grid. Take the time to carefully audit your appliance power demands and map them against generator specifications. This will ensure you end up with the right solar generator to power your essential devices.

Getting the Right Solar Generator for You

Understanding starting vs. running watts is key to getting the right portable solar generator for your specific power needs. Pay close attention to the wattage specifications and match them against your expected appliance loads.

Size the starting and running watts to both startup and continuously run your devices. Also, factor in whether you'll power appliances concurrently to ensure adequate capacity.

With these basics covered, you're equipped to dive into solar generator sizing and specifications. Carefully matching wattages will help guarantee reliable, sufficient power for keeping devices running wherever you roam off-grid.

Common Questions about Starting and Running Watts

Some frequent questions arise when diving into solar generator wattage ratings. We'll address a few key ones here:

Q: How do I find out the starting and running watts for my appliance?
Consult the appliance nameplate or user manual for technical specifications listing its wattage demands. If unavailable, search the appliance model online to find starting and running wattages listed in product details or spec sheets.
Q: Why are some running watts higher than starting watts for appliances?
This is rare but can happen with certain types of heaters. In these instances, the appliance may have a lower initial current surge but draw more continuous power once the heating elements are warmed up. Check heater specs closely for any variance between starting vs running watts.
Q: What happens if I overload running watts on my solar generator?
If you exceed the continuous power capacity of the generator, it will likely overload and shut down automatically. This protective mechanism prevents damage to the inverter and battery from sustained overloads. Make sure to size the running watts appropriately to your typical appliance power needs.
Q: What size solar generator do I need for backup power?
For backup power during outages, first tally up running watts for critical appliances you want to power, like fridge, lights, and phone charging. Choose a generator with enough running watts to cover those items simultaneously. Also, consider sizing up for future power needs. A 2000+ watt unit gives flexibility and room to expand your powered appliances.

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