The Answer



Prius FAQ


Web Links



Internet Control - Saving the Power Grid?

In addition to local control of the car, it can also be turned on by internet connection.  This suggests a host of possibilities, some of them quite significant.  If the car can be started up by remote control via a persistent internet connection, it becomes, in effect, an additional generating station for the power company.  This is potentially true even if the car is in no way connected to the power grid.  Why?  There is no net distinction between bringing additional power on-line, and disconnecting ("shedding," in the jargon) an equivalent amount of load.  This is why, on hot summer days, you will occasionally hear a plea to turn off your air conditioning, relayed over the media from the power company.  The power company's job is to produce and sell power - they will only tell you to use less when they can't make it or risk damage to their facilities by trying to.

Your electric meter

In many states, there are laws allowing customers to generate power and sell it back to the utilities.  This so-called "co-generation" encourages companies to provide for their own power needs and for emergency needs of others by economic suasion.  Although individuals are rarely in the position to take advantage of this, the laws apply to them.  Almost everyone has an electric meter - you can watch it hypnotically turning (and taking your money with each rotation).  If you turn off your appliances one by one, it will progressively slow until it is barely moving, reflecting the tiny load of your turned-off teevee and other gadgets waiting for the zap of the remote control.

Why shouldn't your electric meter go backwards?  No reason at all.  It probably can, if you use a negative amount of electricity.  And you can do just that.  The solar power and wind power folks take advantage of these "renewable" natural resources to generate power whenever they can, whether they need it or not, and either use it themselves, or sell it back to the power company.  Both solar power and wind power (which is generated by solar power, in effect) tend to peak at the same time as peak power demand, and can reduce your demand, possibly to zero or even negative. 

If the power company tells your Prius over the internet "turn on and deliver power" because they can't meet peak demand, you become part of the power system, engaging in co-generation, and helping to keep our voltage where it belongs.  And, you will be paid for it.  You will be paid, laws, policies, or none, by a reduced power bill, or possibly in real money by the power company willing and even eager to pay for the privilege.  Will they do it today?  Maybe - depending on state laws and power company vision.  Will they do it in the future, when the generating capacity of all the hybrid vehicles rivals that of all the power plants?  You bet!

Should you be rubbing your hands with glee contemplating the big bux you'll be making?  Well, no.

The Prius as Electric Generator

As mentioned elsewhere, and emphasized here, the Prius should be considered a source for electricity only in exigent circumstance.  Just as you don't gleefully charge your computer UPS and then unplug it, you shouldn't plan on using the Prius for routine electric needs when you have access to the power grid.  Why?  It's simply not economical.

  • Power company generators are designed for continuous duty.  Cars are less robust and have a more limited lifetime.
  • Power company generators are typically run at their most efficient setting, at a fixed load.  Your Prius will have a varying load and can only be most efficient at a certain setting, which you don't know and can't maintain in any event.
  • Power company generators are more efficient, regardless.  They simply get more power per calorie of chemical energy than do small gasoline or diesel engines.
  • The power company pays less than you do for the fuel that they do use.

While you can consider the Prius on the same terms as solar and wind power in terms of co-generation, the economics is different.  The cost of solar power is almost exclusively one of capital.  The electricity is essentially free - no moving parts, almost no maintenance, no fuel cost.  Wind power is almost as good.  No fuel, although the structure and turbines require maintenance.  To make it as clear (and redundant) as possible:  The Prius is a standby generator, and should not be considered as a primary economical source of power.  If economics isn't a consideration - e.g., the lines are down during a hurricane - the Prius shines.  

The Advantages of Grid Connection

And yet, there are emergencies.  There is terrorism to worry about.  There are periods of peak demand and other power problems.  These all militate for a grid connection.  The potential benefits are substantial, although perhaps less palpable than the "UPS for your house" aspect.  And like many wonderful things in this electronic age, the cost is close to zero.  You already have an internet connection, and possibly a home wireless network.  What would it cost to connect the Prius to the internet, perhaps wirelessly?  $39.95, ($14.99 after manufacturer's mail-in rebate, allow up to a lifetime for receipt).  So why not?

The actual details at the power company end of the grid connection are remarkably technical.  The good folks at  AC Propulsion have spent far more time considering this than you or I, and have authored a number of "white papers" on the subject. 

Vehicle-to-Grid Demonstration Project: Grid Regulation Ancillary Service with a Battery Electric Vehicle (pdf, 1.9 mb)

Integration of Electric Drive Vehicles with the Electric Power Grid -- a New Value Stream (pdf, 1.8 Mb)- Presented at the 18th Electric Vehicle Symposium (EVS18), in Berlin, Germany, October, 2001

And More!

Still to be done...

This page only discusses the issues.  Unlike the other issues, this one is out of my paws entirely.  If the power company decides to implement this, they will no doubt provide a consumer-friendly connection.         

Site 2005/6


  Updated 28 June 2006