Comments

I agree with everything zippo42 said. However, for the information of those who need to know, there are a few key facts and assumptions that need to be made. For instance: 1) Many readers may not notice the difference between the article assuming that people plug in all at once, as soon as they get home, compared to your reference to "off-peak capacity". Everyone should be aware that this term is essentially referring to the the maximum the entire system can generate and carry, compared to how much is used in the middle of the night. Which explains how both situations (yours and the author' s) can be accurate at the same time. 2) That, even though the grid cannot currently handle everyone plugging in their vehicles at once right now, there are power companies working on technology such as the Smart City project mentioned here at http://www.xcelenergy.com/XLWEB/CDA/0%2c3080%2c1-1-1_15531_43141_46932-39884-0_0_0-0%2c00.html , that will eventually make that possible, without the requirement of building new power plants. 3) That battery efficiency, increased sufficiently above current levels, is necessary in order to make PHEV vehicles even cheap enough that we can all afford them. Not to mention the fact that current battery technology would not allow a capable system to retreive much, if any electricity during peak-demand hours through vehicle-to-grid technology, and still get people home at night.