Driving to Net Zero with full performance

Project goals

• Make an electric commuter for daily use, 40 mile round trip• Choose a fun and competent sports car platform• Meet or exceed original performance• Match the annual energy consumed with grid tied solar array

Design philosophy

• Start with an excellent ICE design• Replace ICE drive with equal or greater

performance electric drive• Match the weight and its distribution• Gain confidence in battery cells from a

focused study and gathering real data

Warm up projects

A fun battery test and development platformThis served as my BMS and cell packaging trainer

University of Vermont hybrid electric race car

Oregon State university Solar vehicle

The chosen platform

2003 BMW 325i

Commitment time

A young motor about to be pulled

Brother Randy assisting with the removal

The hanging ICE is destined for craigslist,The BMW is destined for transformation

Motor and Inverter forms

High Tech modeling process:

2040 cell Lithium Ion Battery packCells = A123 systems

Motor comparison

Before and after

New Drive package

Siemens AC induction motor mated with original 5 speed transmission

Installing new drive

The motor installation is now a simple, one person job

Inverter

Blue unit is a 700V 100kW drive (134 HP)150kW drive Inverter going in soon (200 HP)

15kWhr Battery pack

This 700 Volt pack can deliver 1200 amps peak (10sec).Peak demand from 100kW drive system is 13% of that.

Bottom of pack

Primarily for heating in winter, this plumbing uniformly distributes the heat.

With plumbing secured

Inside the pack

Modular format makes for easy access and low/safe voltages when handling

Inside the pack

1 of 30 modules

Inside the Battery pack

Plugging in the BMS slave boards

Fun, Fast and efficient

The range is currently 45 miles, soon to be doubled

I have 6000 miles logged as of March 2011

The Result

Waveform data of my drive to work

Yellow trace is pack VoltageBlue trace is pack Current

700V -->650V -->

0 A -->

Regen Current

Acceleration Current

Power profile of my drive to work

This shows the true power being consumed over 20 mile commute

Average Freeway

Power (16kW)

Other conversion benefits

• Full regenerative braking with high percentage energy capture

• One moving part in motor. No service other than tires and wiper blades

• Can be driven as original Manual transmission intended OR Automatic

• On-board charger can plug into any power source, just carry plug adaptors

• Daily commute costs are 4.7 times less than ICE equivalent at $3.50/gal

Solar array preparations

Started with 70% exposure, need to meet or exceed 75% for grant money.We sent the logs to the local mill with proceeds helping fund the array.5.5kW Array soon to be installed will match annual BMW driving energy. The Blue roof is the planned site for the array, laying flat on surface.

The Christmas tree farm gone wild…

For more detail on this and other projects

www.evdrive.com