Published January 2012: Updated Sunday June 1, 2014


Helping Out the Electric Grid with EVs

Electric vehicle to grid tech interests me very much right now.  Since most vehicles are parked/plugged in 95% of the time, their batteries can be used as backup power for the nearest substation, stabilizing the power grid during periods of peak demand.  

While commercially available EVs currently don't have this capability, they could in the very near future.  The same hardware that converts DC voltage from a battery to an AC waveform for the electric motor could very easily be converted to a 50/60Hz AC that matches the phase and frequency of the local power grid.  

This capability could be as simple as adding some additional hardware and uploading new firmware into the electric car.  

Let me illustrate an example of how this will work:  

Suppose it is a typical hot summer afternoon and the electric grid is fast approaching capacity.  Suddenly, there is a large surge in electrical usage of a particular sub-station.  The grid sends out a message to all available electric cars currently plugged in and charging, "Warning level red, electric capacity of sub-station #15 is at 115% and climbing.  Require an additional 25 kW for the next 20 seconds."   


Three electric vehicles respond to the distress call:  

Vehicle 1:  Sub-station #15, this is Tesla Sedan #1485.  Battery at 80% charge with an estimated departure in 3 hours 15 minutes for a 65 mile round trip classified as "Hair stylist errand -- Sent from I-phone".  Loan use up to 15 kWh at 14.4 kW for the next 65 minutes.  

Vehicle 2:  Sub-station #15, this is Chevrolet Volt #34-7.  Battery at 45% charge with an estimated departure in 7 minutes for a 25 mile on-way trip classified as "Dr appt -- Sent from Android".  Unable to loan use.  

Vehicle 3:  Sub-station #15, this is Nissan Leaf #30665.  Battery at 70% charge with an estimated departure in 57 minutes for a 25 mile round trip classified as "Goto Movies -- Sent from PC".  Loan use up to 5 kWh at 14.4 kW for the next 12 minutes.  

The electric sub-station replies back to the 2 available vehicles:  Vehicle 1, please provide 14.4 kW for the next 90 seconds with payback over the next 30 minutes.  Vehicle 3 please provide 11 kW for the next 60 seconds with payback over the next 20 minutes.  

The grid is stabilized!  The electric cars just saved the day and the humans continue going on with their lives, unaware that the entire neighborhood was just spared having a power outage.  Life is good.  

Update:  6-1-2014

Free, sustainable, perpetual, on or off-grid full house power will be available very soon. It is certainly do-able right now, you just need the right ingredients: 

An energy efficient home, a PV solar array, an EV and this fancy new gadget








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