Underside of rear endFront endEngine compartmentMiata seatsThe office areaTrunk
OwnerMike Sasnett
LocationLos Altos, California US map
Email email image
Vehicle1973 Porsche 914
Arrived here orange and hollowed out (engine-less) on Halloween 2006. Instant name!
MotorAzure Dynamics/Solectria AC24 3-Phase AC
ControllerAzure Dynamics/Solectria DMOC445
Regenerative braking extends the range a little, especially in stop & go driving. Saving the friction brakes is probably the best effect.
Batteries14 Deka 8G24M, 12.00 Volt, Lead-Acid, Gel
Performance of the Azure Dynamics motor-controller would be compromised by using the standard Electro Automotive 144-volt traction pack -- a limit imposed by the DC-DC converters they offer. Decided to avoid the problem by developing a DC-DC converter capable of operating at up to 200 V input. This turned out to be a good choice.
System Voltage168 Volts
ChargerZivan NG3
Heater(none) Hey, it's California!
DC/DC Converter MS Special
Uses 2 Vicor BatMod modules with packaging and control circuitry that I designed. Functions as the main power source for 12-volt system and as charger and maintainer for the back-up battery.

Input: 100 to 200 VDC
Output:
Key on: 13.5 V, 28 A max
Key off
Recharge: To 15 V max, 3.7 amps max
Float: 13.0 V
InstrumentationStandard Porsche 914 instruments plus current and voltage meters for the traction motor.
Top Speed70 MPH (112 KPH)
Acceleration0 to 30 mph 9.8 sec
0 to 40 mph 14.5 sec
No Tesla but it feels peppy enough.
Range30 Miles (48 Kilometers)
Watt Hours/Mile350 Wh/Mile
Calculated using energy drawn by the Zivan charger to fully recharge the pack, as measured by a kW-hour meter on a dedicated 240 VAC line to the charger.
Seating Capacity2 adults
Curb Weight2,600 Pounds (1,181 Kilograms)
Weight distribution 50/50 front/rear
Conversion Time9 months of work on the car preceded by about 10 months of design and development work on the DC-DC converter.
Conversion Cost$20k (approx)
Additional FeaturesPhoto-voltaic panels on the house roof produce electricity during the afternoon for which the power company credits us at a high rate per kW-hour. We delay re-charging until the evening when the electricity price is lower. The net effect is zero cost for electricity for both the house and car. What we would otherwise pay for gasoline helps amortize the cost of the PV array.

Use of Electro Automotive parts definitely shortened the development time. Battery racks and motor-to-transaxle adapter parts have worked out well.

code by jerry