Hunting Happiness

More details have become available about the Chevy Volt. The Volt is a gas-electric hybrid but it has several key distinctions from anything currently on the market. It is expected to have a 40 mile range without using any gas.

• It can plug into standard 110V household receptacle to charge its batteries
• While is does have a gasoline engine, it is not connected to the driveline.  Instead, its sole purpose is to run a generator to charge the batteries in the event the 40 mile range is exceeded.
• In current spec it uses Lithium Ion batteries

This is potentially a revolutionary shift in automobiles and the hybrid arena in particular. The theory is that most Americans drive less than 40 miles round trip to their jobs and could thus use gas only as a backup. According to the articles, a total range of about 600 miles is expected.

So could it save money? That is a little trickier to compute, especially because there’s a discrepancy in the article. I detail that below but let’s ignore that for now.

Let’s assume that your roundtrip commute is exactly 40 miles. This is a best case scenario for the Volt.

VOLT: In our part of the country, electricity is approximately 8 cents per kilowatt-hour (kWh). The battery is 16kW so a battery “fill-up” costs $1.28 in electricity. So it costs $1.28 per day to commute to and from work, or about 3.2 cents per mile.

Normal Car: Assume 25 MPG and regular gas is $3.50 per gallon. The roundtrip requires 1.6 gallons of gas which would cost $5.60. So it costs $5.60 per day to commute to and from work, or about 14 cents per mile.

Over the course of a year (assuming 240 commutes to/from work),  the Volt could save ~$1,000/year in gasoline expenses.

Even if you plug in a Toyota Prius getting 50 MPG, the Volt is still half the cost. Again this is an ideal situation for the Volt and assumes that it bears no other additional costs that a gasoline car would not.

Potential Issues

The article mentions the battery capacity is 16 kWh, but that it should charge in 6-6.5 hours.  The issue is that a standard US receptacle is 15A which can supply only 1.8kW per hour, assuming a perfect power factor correction (unlikely).  Even a not-unusual 20A would require 6.7 hours, again assuming an unlikely perfect power factor correction.  So either my power math is rusty, the battery capacity isn’t 16 kWh, or there’s some funny business going on with the charging time.  Perhaps it CAN use a 110V outlet, but the charging time mentioned assumes a 220/240V supply.   Who knows.

There is also the issue of the Volt’s use of Lithium Ion battery technology.  These typically pack twice of the energy density of NiMH batteries that Toyota and others use in their hybrids.  There is concern over the reliability of Li-ion and a propensity to fail catastrophically (ie explode).  Chevy is currently undergoing durability testing which could lead to delays or even a switch to older battery technology.

The original target date for market release was 2009 but it appears to be pushed back to 2010 now.

If and when the Volt becomes available, and if its specs are in line with those above, it could be a nice way to cut some costs and to help the environment.  Of course, some will argue that the power-plant production of electricity to charge the car is more harmful than the emissions from a traditional gasoline car but that is a whole other can of worms.