[Chasedown]

Originally Posted by Shankenstein

Purely hypothetical discussion ahead. Turn back all ye who may say "this is stupid!"

If an exhaust turbine and wastegate are installed on our engine, what is an example of turbine shaft torque and speed? How much energy (temperature and pressure above atmospheric) can be used for regeneration?

Two options for generating power:
- gear down heavily and employ a high-output alternator
- run a DC electric motor in reverse

Similarly, can an intake compressor be run from a DC motor? Not talking the tiny electric superchargers on eBay... I'm talking voltage step-up + 1/2 hp dc motor + centrifugal/twin screw compressor (a la Vortech).

The idea has been tossed around by Subaru: HERE for the next WRX.

I'm just trying to wrap my head around how challenging this would be.

Potential issues:
- Sizing a battery/capacitor bank
- Management of alternator clutching
- Management of battery/capacitor bank discharge rate
- Integrated BOV with instant pressure relief (compressor motor braking)
- Cost and hardware weight would be high.

Potential awesome:
- No lag, as long as you've got battery power.
- Boost pressure can be closely controlled via dedicated feedback controller.
- The system can be switched to "ECO" mode for regenerating energy to supplement the alternator (would require an isolator for starting battery).
- The system can be switched off completely.
- Combination of the above. ECO mode during low load, low rpm driving. Instantly switch on above X% load.

Comments? Discussion?

I've been wondering the same thing since I heard about the possible hybrid evo and the new wrx. Wouldn't another solution be to use the electricity to power an electric motor for the actual drive train? Subarus one big hit in the past has been fuel economy. Adding a generator in the exhaust to power an electric motor with the 2.5 n/a motor should generate more combined HP than the last wrx and improve fuel economy.
My idea, an over simplified system is a centrifugal (?) Supercharger in the exhaust system going in the outlet of the supercharger hooked to a higher power alternator hooked to an electric motor. You be providing power as long as the exhaust was flowing... I dunno though I'm not up with electric stuff so I'm sure there is some complicated reason that wouldn't work. Just figured using a centrifugal (?) Supercharger would help cause they already have built in transmissions to switch the couple thousand RpMs into tens of thousands of rpms for the blower so the opposite should be true to run an alternator or generator.

Oh and I said Subaru cause its basically Subaru's engine with Toyota technology lol.