Gen-Save energy recovery and control solution for high-TDS RO applications

The energy recovery solution for high‑TDS RO

In textile, pharmaceutical, and chemical wastewater treatment, high-TDS RO up-concentration is energy-intensive – but energy recovery has traditionally been out of reach.

Unlike SWRO, strict process and purity requirements allow no mixing between feed and reject streams, so isobaric ERDs are not suitable. In most cases, control valves simply dissipate the reject stream’s high pressure, recovering none of its high energy potential.

Now, the Danfoss Gen‑Save turns previously “unrecoverable” energy into real, measurable savings.
Engineered for demanding single- and multi-stage RO up-concentration, Gen-Save recovers up to 80% of otherwise wasted energy – all with zero mixing. Its complete hydraulic isolation maintains feed purity, while built-in pressure control eliminates the need for high-pressure valves.

Powered by Danfoss Axial Piston Motors and Variable Frequency Drives, Gen-Save simplifies system architecture and delivers full flow control – all in one compact, integrated package.

An active energy recovery solution, Gen-Save operates reliably even in fouling- and scaling-prone environments, ensuring consistent performance under the most challenging process conditions.

Where high‑TDS RO systems leave energy on the table, Gen‑Save puts it back to work.

Benefits:

Recovers up to 80% of energy where other ERDs can’t
Zero mixing with full hydraulic isolation
Eliminates the need for high-pressure valves
Seamless, integrated solution with Danfoss APMs and VFDs

See how Danfoss Gen-Save is unlocking energy recovery in high-TDS RO where others can't.

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See how fluvicon uses Danfoss Gen-Save to recover energy and simplify high-TDS RO in industrial wastewater treatment.

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FAQ

What are the ideal application areas for Gen-Save?

Gen-Save is designed for high-TDS RO up-concentration processes – single or multi-stage – where no mixing between feed and reject streams is permissible. It’s ideal for wastewater treatment in the chemical, pharmaceutical, and textile industries, especially where control valves are used. Gen-Save replaces these valves while recovering energy, reducing electricity use, cutting CO₂ emissions, and saving operating costs.

What is the typical payback period for a Gen-Save?

It depends on your flow rate, operating pressure, recovery rate, and energy costs. In high-flow, high-pressure systems, payback can often be under a year. Lower flow and pressure may result in longer payback. To calculate accurately, we’ll need basic operating data: energy prices, flow rate, pressure, and recovery rate.

Can Gen-Save be used with non-Danfoss pumps as motors? What are the trade-offs?

Yes, Gen-Save can be integrated with third-party pumps as motors. However, for maximum energy efficiency and performance, we recommend pairing it with Danfoss axial piston motors, which are among the most efficient on the market. In retrofits, we can work with your existing pumps to design a tailored solution.

Is Gen-Save affected by fouling or scaling in wastewater streams?

No. Gen-Save is an active energy recovery device designed for reliable operation in challenging conditions. Its Axial Piston Motor is connected to an electric motor that acts as a generator during normal operation. During startup, the system powers the generator as a motor to ensure controlled rotation and smooth transition to energy recovery mode. This active control prevents startup issues and keeps Gen-Save performing consistently even in scaling- and fouling-prone environments.

How is Gen-Save controlled?

Gen-Save operates via Variable Frequency Drives (VFD) and is easy to commission and adjust. Flow and pressure are controlled by RPM, which can be set during start-up and changed later if needed. Control options include analog input for pressure, flow, TDS, or fixed RPM, making the system flexible and easy to integrate.

If Gen-Save is so effective, why hasn’t it been introduced before now?

The water treatment industry has long focused on seawater reverse osmosis (SWRO), where energy recovery has seen major advances. But industrial wastewater applications – with complex process requirements – have been underserved. Gen-Save fills this gap with a solution specifically engineered for high-TDS, zero-mixing systems.

Where do I start if I’m interested in learning more about Gen-Save for my application?

Simple. Contact our Danfoss sales team with your flow, pressure, and recovery rate. We’ll help assess your process and propose a tailored Gen-Save solution so you can start saving energy, money, and emissions.

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