Can you run a Welder on Solar Power?

You can operate your welder on solar power as long as your PV solar system can deliver enough electricity to power it.

A welding machine is not the most energy-intensive equipment. However, if you do a lot of welding, relying on the grid to power your welder can cost you a ton.

With solar panels, a charge controller, batteries, and an inverter, you can harness the sun's energy, store it and transform it to electricity that you can use to potentially power your welder.

This post will teach you everything you need to know about powering your welder with solar power and off-grid welding in general.

What is Solar Welding?

Simply put, solar welding is using solar to run a welding machine. A welder can also run off a generator or the grid, but solar is exceptional for being cost-effective and environment-safe.

As solar becomes more integrated into critical processes like welding, we have hope that it’ll eventually power most of our everyday activities.

The topic of solar welding is vast, but let's start by examining the effectiveness of using solar power to run a welder.

A Welder can be Powered by Solar Power for Light Fabrication Works

Under average solar conditions, the power produced by solar panels is only enough for light welding tasks.

To better understand this, let's briefly look at what the power consumption of a welder is like.

Welding uses high intensity regulated arc, which simply means a huge current for a short period.

At the start of every weld, there're significant current surges, also known as surging watts that most solar PV systems aren't made to handle.

Surging watts are always higher (usually 25-30% higher) than running watts; the power needed to continue running the welder. Your solar PV system should be able to handle both surging and running power.

Example:

If you have a welder with a surge watt rating of 2500W and a running watt rating of 2000W, then you’ll need a PV setup that produces at least 2500W even at the lowest operating efficiency.

A 2000W setup may not work in this situation as it’ll not handle the 2500W surge power.

A conventional welder consumes around 10 kilowatts per hour.

The overall power consumed depends on these basic factors:

Size of the welder- Larger welders have more powerful transformers hence consume more power than their smaller counterparts.
The heat dissipated by the welding machine- The more heat a welder produces, the more power it consumes. Note that a lot of heat dissipation could translate to poor performance.
Efficiency- The higher the efficiency, the less power a welding machine will consume for a given running time.
Welding time- Welding is never a long process. Even so, the time you take joining your metals is directly proportional to the power consumed.
Output Voltage and Output Current- When welding, you adjust the output current and output voltage depending on how heavy the material you're welding is. The welder will definitely need more power when working on heavy metals.

Determine the power consumption of your welder

To calculate the specific power consumption of your welder, use this formula:

Power in kW = (Output Voltage × Output Current)/ Efficiency

Example:

Let say your welder operates at these conditions:

Output voltage- 24V
Output Current- 160A
Efficiency- 90%

Power in W= (24*160)/.9 = 4266W

4266W or 4.27kW is the power consumption of your welder per hour.

If the welder was to run for 20 minutes, then its power consumption should be (20/60) *4.27 = 1.42kW.

It may seem like an unnecessary expense to turn your welding machine to solar, but you should know that even the smallest amount of welding time you have off batteries is far more economical than depending on the grid.

And I have some good news for you. You can use the strategies discussed below to leverage solar power optimally in welding.

How to Get the Most out of Solar Welding?

Pick noontime as your best welding time

The sun shines best at noon, so this should be your go-to welding time. You can do the marking and cutting in the morning, then tap into the free energy when it's available in abundance at midday.

Improve your rod technique

When you have insufficient solar power to run your welder, you need to improve rod technique so that you can work around your welding and base metals in the shortest time possible.

Prepare your metals before you switch on your welder

From marking and cutting to weld cleaning, do all that’s needed to get the materials ready for welding before you switch on the welder.

By doing this, you’ll eliminate time wastage when you start working on your metals.

Have a dedicated PV setup for the welder

Instead of putting extra power demand on your main PV system, build a separate solar power setup for your welding machine.

Invest in a large battery bank

A running solar welding machine gets its power from the solar battery. It's only with a large battery that you'll keep your welder running for an extended period.

Large batteries are also less prone to over-draining, which can easily happen if you use a low-capacity battery.

Don’t even think of running your welder directly from solar panels, as this will translate to totally relying on the unpredictable sun on.

Build your solar PV system with the surge watt in mind

To operate in full capability, you need to ensure that your solar PV system can provide the highest operating power the welder needs.

Most welders will have a wattage value on their model name. Confirm if this is surging or running watt, so you can know what size of a solar PV setup you need for your welder.

Get a pure sine inverter

A pure sine inverter produces clean and quiet electricity, not to mention that it avails extended power backup. These features make running a welder off a pure sine inverter one of the best tricks for efficient solar welding.

With these critical insights, we can now comfortably proceed to setting up the PV setup and hooking up the welder.

How to run a Welder on Solar?

To run a welder on solar, you'll need solar panels, a charge controller, batteries, and an inverter as the main basic components.

Following are the roles of each of these components:

Solar panels- The role of solar panels is to collect the sun's rays and convert them to DC power.
Charge controller- This is the heart of any solar PV system setup. It regulates the power from the solar panels and delivers only what is enough to charge the batteries in the system.
Batteries- The batteries store the power produced by the solar panels. You can tap into this power to run your welding machine.
Inverter- This crucial component makes the vital DC to AC transformation of the power stored in the batteries. With AC power, you can run any electrical machine, including your welder.

For steady and occasional welding, I would recommend this combination:

4 * 100W, 12V solar panels
2* 200 AH, 24V batteries
1800W pure sine wave inverter

Here's the procedure you should follow to run a welder on solar panels using the above components:

1. Connect the solar panels in series

To do this, snap the positive terminal of the first solar panel to the negative of the second. Repeat this for all the solar panels.

Before connecting solar panels in series, always ensure that the total voltage of the modules conforms to the total voltage of your batteries.

Our 4* 12V solar panels will produce 12*4= 48V when connected in series.

2. Wire the batteries in series

Connect the batteries from the positive terminal of one to the negative of the other.

Like in the above connection, a series connection of two 24V batteries will yield a total voltage of 24*2= 48V.

3. Fix the inverter between the solar panels and the batteries

Use DC wires with gauges and a battery connector wire to make an inverter connected between the solar panels and the batteries.

4. Follow the pure sine inverter’s manual to wire it to the battery setup

Pro tip: Keep the wires as short as possible to eliminate any potential power losses. Also, don’t forget to add a DC safety disconnect at some point in the battery bank-inverter connection for troubleshooting and maintenance purposes.

5. Lastly, connect the welder to the inverter

You can use a power adapter to hook up the welder to the socket output of the inverter. With this, you just need to connect your torch (electrode holder) and earthing clamp to the welder and get rolling with beading.

Now that you know how to power a solar welder with solar power, you should ask yourself this question:

What Welder Should I use with my Solar PV Setup?

Welders are categorized based on the polarity of current they produce: AC or DC.

AC welders use alternating polarity current and are suitable for thick metals, aluminum, and magnetic materials welding.

DC welders use direct polarity current and are perfect for everyday solar welding. They offer smooth welding with no spatter and can also handle heavy applications.

There're welders with both AC and DC functions, but these come with a high price tag. With the money, though, you can acquire an AC-DC welder and enjoy the unlimited applicability it comes with.

For standard welding and with the power from a solar PV setup, I would recommend the DC welder.

Cost of a Good DC Solar Welder

The prices of DC welding machines start from lows of $30 to upwards of $700, depending on capability.

You should evaluate the scope of your welding work to know what welder you should buy.

A good 120-240V DC welder suitable for everyday welding should cost you around $120.

Note: DC welders have an internal electronic component that changes the alternating polarity of the current from your module-battery-inverter setup to straight polarity current. This adds to their size and slightly to their price when compared to AC welders.

Benefits of Solar Welding

Excellent convenience

Solar panels can power a welding machine anytime, anywhere. You get to do your welding work even when you're off-grid.

Cost-saving

You'll not save hundreds of dollars for running your welder with solar panels, but you'll definitely note an offset on your monthly electricity bills. If you're a professional welder, this should be the main reason to solarize your welding machine.

Environment-safe

Anything that's powered by solar saves the environment from pollution caused by burning fossil fuels to produce electricity.

Limitations of Solar Welding

Welding is subject to the available sun

If there're clouds all day through, you may not harness the power needed to run your welder.

Hefty initial investment

If you've invested in solar power before, you know the initial investment digs dip into your pockets.

Save More by Spending Less with Solar Welding

Solar power will not run a 200-amp weld bead for hours, but you can actually do some light repairs.

To say the least, this is all you need to cut down on your electricity bills.

What's more, by tapping into the strategies given in this guide, you can maximize your solar welding hours.

So, if you have a welding machine that's digging dip into the grid power and your pockets, you need to turn it to solar!