While using the Hydraulic Power Regeneration System (HPRS), the mechanical or exhaust brakes can be added to the braking force to quicken deceleration.

In power regeneration programs they work together. Tail shaft drop box regeneration systems, such as EATON HLA, have one advantage as they are an analogue system – i.e. It is infinitely variable to adjust the braking power and is smooth.  However, there is the step-up gearbox, clutch and expensive heavy piston pump giving high cost and weight.

Disadvantages of such systems include:

• It cannot work over 40 KPH.
• Has poor performance below 10 KPH as the piston pump shaft speed is low.
• They work to 420 bar/6,000 PSI to try to accommodate these limitations.
• The pump can not be used for any other function.
• They have to carry separate oil reservoirs, as they need super clean oil – No steering, tipper etc, type hydraulic systems can share the special oil.

With the HPRS, it is fitted to the engine side of the gearbox and the pump/motors are running at close to optimum speeds regardless of road speed.

Advantages of HPRS include:

• The pumps can work to 100+ KPH and still act as brakes and regenerators.
• Our pumps can be used for tipper, steering, waste collection etc.
• Three pumps give seven steps, and gearbox changes occur simultaneously for smooth operation
• Adding the on/off power steering pump gives four pumps and up to 25 steps in a digital mode, and at the same time the gearbox is changing gears again.

Thus we can save and reuse more energy; save cost and save weight. On tippers/concrete agitators and the like, we already have an oil reservoir of considerable capacity.