Using a Solar Generator for Power Tools May Be a Possibility… It Depends on How You Play the Game
We absolutely loved what Kohler did in creating the enCUBE solar recharging generator. Using a 100 amp hour AGM lead acid battery, there’s enough power stored to run a variety of products for your home, office, shop, or even jobsite if there’s an issue with the power source or a lack of power all together. That made me wonder – could using a solar generator for power tools create a cordless jobsite?
The question is relative of course. It might be more fair to ask if it is possible to create an off the grid jobsite. Even though there are plenty of recommendations of what you can run on a given generator in manuals and online, that doesn’t always translate to power tools since their energy demands are different than say, a refrigerator or microwave.
The Kohler enCUBE is pretty much top dog when it comes to converting DC to AC power as a portable generator. It’s capable of delivering 3600 peak watts for start up, 1800 watts for ten continuous minutes, and 1440 sustained watts. There are a pair of 5 amp USB ports, two 12 volt vehicle power ports, and two 120 volt AC outlets. There’s also a positive/negative connection on the back that can be used for jump starting or to daisy chain another battery (possibly more).
False Start
With that kind of power available, we set out to discover what we could run. Battery chargers are a no-brainer. The low level draw they require means your entire suite of cordless tool battery packs can remain charged. From there, Clint and I started big. Real big. 15 amp, 12-inch miter saw big. You’ll never guess what happened.
Nothing.
The generator has enough muscle to run the saw based on what we know from its power requirements on paper. Whether 3600 watts wasn’t enough or it couldn’t produce it long enough, the enCUBE just wasn’t able to overcome the start up power needed. 10-inch miter saws are going to be in the same boat since most professional saws also run a 15 amp motor.
From there, we moved down to our Bosch 8-1/2 inch compact miter saw. This time we got somewhere. The enCUBE tried to get the blade spinning, but again, the saw just needed a little too much start up juice than we could get. We were actually able to get the saw going by tapping the trigger quickly and repeatedly. We also won’t argue that it’s a reliable way to plan on using the either the generator or the saw – so just don’t do it.
First Down
Next came a 6.6 amp grinder. The enCUBE ran this tool beautifully. We tried to really bear down on the abrasive disk to see if we could peak the output beyond the 1800 watts it is rated to sustain for a short period. We didn’t come anywhere close.
With a solid success to hang our hats on, we moved up again. This time it was Milwaukee’s 11 amp Super Sawzall. Tim Johnson will be quick to point out that it’s his 50th anniversary special edition. From start up to cutting, the enCUBE was able to deliver consistent power for the recip saw to cut just like it was plugged into the wall.
Powering the Drive
What we discovered is that using a solar powered generator to create an effective off the grid jobsite isn’t necessarily plausible. You’re pretty much limited to tools that run an 11 amp motor or less, but even that’s a wide generalization. Tools with a soft start have a better chance of getting started than models that just get right after it.
Cordless tools, on the other hand, are wide open. That’s where we think the enCUBE is going to be your best friend. With options like DeWalt’s FlexVolt line offering a cordless table saw and miter saw or Milwaukee’s M18 Fuel line bringing a cordless miter saw to the party, you have some realistic ways to be off the power grid while still delivering results with professional level tools.
Overtime
We know that for many of you, 10 hour days are the short ones – particularly during these summer months. The real limitation on using a solar charging generator for power tools is going to come down to the power source and the recharge rate.
The enCUBE comes with a 100 amp hour battery and replacements are on the market to get you up to 125 amp hours. Using a lead acid battery, it’s recommended that you don’t draw the battery down below 20% to get the most out of it.
With 60 watt solar panels, I was able to get a consistent 45 watts of charging power back into the unit. That’s a recharging cycle of roughly 21 hours if I stick to the 20% max discharge rule. With the 150 watt option, I can expect 110 – 115 watts and a recharge time of somewhere in the neighborhood of 8-1/2 hours.
If you go with the higher panel option, you can likely get 2 full charges worth of power out of a solar generator over the course of your day in excellent conditions. On a completely cordless platform, perhaps supplemented with a corded reciprocating saw, grinder, or other hand held power tools, you can probably get through the entire day without connecting to a power source that’s on the grid.
Post Game Coverage
We started the day wondering if using a solar generator for power tools could be a realistic option. Our results?
Mixed.
We think it’s a real possibility for Pros who are going to be using mainly cordless and sub-12 amp corded tools. You really need to consider having at least 150 watts of solar panels to make it through your work day.
Taking your entire trailer off the grid including miter saws, table saws, and other high draw tools won’t work though.
The benefits are pretty obvious. You’re leaving a smaller environmental footprint by using off the grid power generated by the sun. That’s assuming you recycle your battery when it’s time to replace it. That could be every 5 – 6 years if you’re maintaining it properly.
You’re also reducing the noise and emissions of a gas generator down to zero in both categories. Like all battery powered tools, there are no emissions. The Kohler enCUBE is also silent running, save for a small cooling fan.
The really cool thing is that this is just the first step for Kohler. They’ve got a solid platform with the enCUBE. I’m hoping that as lithium-ion technology continues to develop and decrease in price that we’ll see a generation capable of running those 15 amp tools and offering even greater run time.
