...how would that be worse?

 

I kind of like the concept of an electric driven compressor.

On the negative side, you are using electricity generated by the ICE and taking a big efficiency hit on the conversions.

On the plus side, you can run the compressor at steady speed (design point) which is great for AC compressor efficiency, and either unload it or shut it down when it's not needed.

Obviously the AC system will have to go this way on future Plug In Hybrids.

 

ICE to GEN to A/C motor should be close to belt drive from the ICE efficiency.

In addition:

1. Modulating the A/C motor torque will match it to the cooling load. It wil use less energy except when max cooling is needed.

2. The ICE does not need to drive a compressor belt, puly and clutch when the A/C compressor is not needed.

3. A/C could be run from the battery when the ICE is not needed. (higher capacity batteries may be needed).

4 A varaible capacity compressor increases comfort!

 

Does anyone do 1 and 4? Room A/C and A/C's for houses that I've SEEN are all either ON or OFF... they just cycle more frequently. If they don't... why not? I'm not an A/C expert so I'm just wondering if there isn't a reason it isn't done in these larger models where it would presumably be easier.

 

VW uses a variable displacement a/c compressor. when it fails it cost about $1400.00 for the part.

 

VFDs are applied to commercial compressors now. Residential versions using permanent magnet electronically commutated motors (ECM) will be common soon.

Variable displacement compressors are usually vane or screw compressors with mechanical unloaders.

ECM motors have been slow coming to the HVAC market. But, legislated mimimum efficiencies are forcing residentail furnace and AC manufactures to these motors. They have been in premium furnace/AC unit condensors and evaporators for 10 years. But nhot on the compressor. Just wait a year!

 

"..the AC system will have to go this way on future Plug in Hybrids.."

Not if I am successful in designing a highly efficient and quiet, SUPER QUIET, 2-5 HP fossil fueled HEAT PUMP. Heat and/or cool the passenger cabin.

 

SHOW IT TO ME WILLARD!!!
SHOW IT TO ME!
-John

 

Water cooled, exhaust is cooled and quieted by integral radiator/muffler/heat-exchanger combination including electronic noise cancelling. Electric clutch to couple engine to alternator/compressor. Solid state inverter 60 hz 125 VAC 3000 watt output (2000W with variable displacement A/C compressor at "full" bore). Inverter is used to drive the alternator "motor" when on shore power or as the "ICE" starting motor.

EFI engine using the Miller cycle. Small variable speed synchronous AC motor "super" charger w/intercooler to meter/force the intake airflow and help quiet the intake noise.

15,000 btu HEAT/COOL (heat pump reversing valve), w/heating capability below 20F via ICE heat extraction.

Complex, EXPENSIVE...YES.

But in the RV market it surplants the need for separate genset, furnace, and A/C.