Electric vs Hydraulic Injection Molding Machines: What Actually Changes

Every injection molding machine buyer eventually asks the same question: is it worth moving from a hydraulic machine to a full-electric one? The honest answer is that it depends on what the process actually needs — but the differences are consistent enough to lay out clearly, and large enough to be worth calculating for your own plant.

The Energy Math: a Concrete Example

Take a realistic case: a 150-ton hydraulic machine draws around 30 kW on average during production, because the pump also runs during cooling and holding, when no axis is moving. An equivalent all-electric machine molding the same part averages around 12 kW, because servo motors draw current only while an axis actually moves.

That 18 kW difference over 6,000 working hours per year adds up to 108,000 kWh annually. At an industrial electricity price of 0.14 €/kWh, that is over 15,000 € saved per year — on electricity alone, per machine. Over five years the difference exceeds 75,000 €, which for mid-tonnage machines is a substantial share of the machine price itself.

Enter your own parameters into the calculator at the bottom of this page to see the savings for your plant.

Precision and Repeatability

On a full-electric machine, every axis — injection, clamping, ejection — is driven by its own servo motor with an absolute encoder, rather than a shared hydraulic pump and valves. That gives repeatable positioning to around 0.01 mm, CNC-machine territory, which matters most on thin-wall parts, tight-tolerance technical components and multi-cavity molds where shot-to-shot consistency across cavities is critical.

Cleanliness and Maintenance

No hydraulic oil means no oil changes, no oil disposal, no risk of an oil leak contaminating a mold or a cleanroom-adjacent process, and generally lower long-term maintenance costs. This is one reason electric machines are the standard in medical and pharmaceutical molding and food packaging, where cleanroom production is required.

Where Hydraulic Still Holds Up

Tonnage is not a reason to choose hydraulic — the JSW all-electric range covers the full span from 30 to 3000 tons, including ultra-large 2-platen versions. Hydraulic and hybrid machines still make sense where the deciding factor is the purchase price itself — for example on tooling that will only run a few thousand hours in total (prototype or bridge production), where energy savings simply don't have time to pay back. For everything else — technical parts, cleanrooms and multi-shift plants — the math increasingly favors all-electric.

Perotec Systems supplies Japan Steel Works (JSW) full-electric injection molding machines from 30 to 3000 tons, including ultra-large 2-platen versions and vertical insert-molding models. Contact us to work through the tonnage, precision and cycle-time requirements for your application.