How does the hybrid system work

[Glover]

Probably a silly question but when the display is showing the ICE and motor/s are working at the same time and you're just cruising at sixty on a flat road is that for fuel saving?  As my car doesn't have a rev counter I'm not sure what impact it has in terms of revs; do these drop when the electric motor/s kick in?  Hope this makes sense!

[Verbout]

http://lmgtfy.com/?q=Lexus+hybrid+engine

[ColinBarber]

The engine revs will be lower if it is getting Battery assist. Normally on a flat road at a constant speed it will provide a bit of assistance if the Battery level is high - it doesn't make sense for it to do this indefinitely as the Battery charge will drop to a point where the engine has to charge it up again which is inefficient because of the energy loss in converting power from the engine to electricity.

If your Battery charge was low the engine would both power the wheels and drive the generator to provide charge.

[paulrnx]

The batteries and motor(s) are there to augment the petrol engine as and when the brain decides it needs both. Not just for full EV mode. There can be a significant difference in acceleration between petrol engine + electric and just the petrol engine. In my NX I had a part of a regular journey where a unique combination of factors always LED to me accelerating up a hill having joined a dual carriageway just as the batteries were just about fully depleted. Occasionally it was obvious that I was only getting 154BHP & torque out of the petrol engine alone. First time it happened I was convinced I was dragging an anchor somewhere.

[Glover]

Thanks all.  The google link is excellent Garry.

That makes sense; so if I've got that right when the batteries are sufficiently charged it will use the electric motors at any speed in conjunction with the ICE to reduce the power required from the ICE = better fuel consumption or alternatively give a boost when accelerating.  I just had one of those moments when, although I'd seen it lots of times before, I thought; is that to improve economy?  Very clever technology.  I'm always amazed by how seamless the technology is; in fact I'm always amazed by Lexus!