Sounds like the "Hustler" beast skimmer...

It is the beast skimmer. And I wouldn't sell it because it pulls so much. And I'm planning a bigger tank. And wanna keep it

I would think that part-time skimming is better than no skimming. Things I would look at: how does it do on startup? Does it overflow or anything on the first surge? (Mine does, I have to turn the air valve on slowly..) When it's off, does it empty back into the sump and affect the level for ATO? Do you get skimmate gunk on the inside walls that might dry out if left off for a few hours?

What component is the power draw? Is it a separate feed pump? You could throttle it back, which would have the dual benefit of drawing less energy, plus increasing contact time.

It's a becket skimmer. It's all one pump

There's no overflow. It's always consistent.

you may have to look at how long it takes to start skimming, mine takes a bit of time before it pushes the bubble column into the collection cup, so if i were to run it for a couple hours and shut it off it wouldnt do much skimming.

I don't see a problem with running it off and on. Although if it was me I would run it for 8 hrs a day and start it at 3am till 11am. That way if you feed heavy there will be some time for the food to get to the sps. Also sps mostly feed when the lights go out, so in this case atleast the sps will get some food before the skimmer starts.

I feed quite heavy twice a week and during this time offline my return pump for 5 hrs so that all the corals get a chance to eat. I have been doing this for a few months and every coral seems to Benifit from the broadcast feeding. It's the only way I can feed my corals without the fish stealing the food. The fish eat so much they don't want to stare at food anymore then some of the corals get target fed and the rest get the slurry of food.

The skimmer is likely to pull out nearly as much gunk even if only turned on for a few hours. This would just cause fluctuation in oxygen/CO2/pH/DOC levels.

Is the tank well stocked with corals? If so, just feed the water column in the evenings with Oyster Feast, Reef Chili, frozen Cyclopeeze, etc a few times per week. The skimmer and clean up crew will have all the food taken cleaned up by morning when the lights hit the tank. Make sure to include a healthy serving of clean up crew and you're golden. You will get mad PE with this approach.