Cody Hyman

 The Base Load Power Plants  Always active and feeding the grid  Mostly Coal and Nuclear  Intermediate and Peaking Power Plants  Activated when power demand increases  Includes smaller fossil fuel plants and hydroelectricity  Supplemented by forms of Alternative Energy Source:

 The greater the demand for power, the more current the power plants must provide  Power companies need to provide a relatively constant AC voltage and frequency to customers  The power transmission and distribution grid of a developed nation like the US is an incredibly complex and constantly changing circuit

 Large Fluctuation Between Day and Night Power Demand (lowest demand may be around 60% of peak demand)  Grid must quickly compensate for changes in demand  Additionally, demand varies by other factors including the local climate and season

Image taken from California ISO state grid data for 13 October 2009 Current grid data can be found at

 If demand is too great, outages occur  Dropouts, brownouts, and blackouts  Rolling blackouts are created intentionally to keep the grid partially up while demand is too great for the grid to support  Most surplus energy, if there is any, is lost

 Organizations managing the grid predict load curves  ex: the California ISO  Number of connected generators is varied  Spinning reserves and peaking plants supply extra power during peak demand  Stored energy is sometimes fed into the grid

 Some energy can be stored for use during peak hours  Only a small fraction is stored currently due to the expense of storing energy  Intermittent power sources such as wind and solar may suddenly stop generating power, causing a large droop in the grid  Storage methods include  Batteries (Very efficient, but expensive)  Pumping water for hydroelectricity  Gas Compression 1  Flywheels (Steadying Voltage and UPSs) HowStuffWorks. Grid Energy Storage. 1-

 Great increase in total grid demand as more electric vehicles are put on the road  Off-Peak Night Charging to fill “valleys” in the demand curve  The Pacific Northwest National Lab estimate: approximately 70% of an EV based American road transportation system could be charged on current generation capacity  Would decrease the amount of necessary grid expansion PHEV Projections obtained from PNWNL:

 PNWNL estimates the following energy requirements for hybrid electric vehicles with an average generator to battery efficiency of around 68-70% (includes transmission and distribution losses as well as charger and battery inefficiencies)  Compact Cars 0.26kWh/mi  Mid-Sized Cars 0.30kWh/mi  Mid-Size SUVs/Vans 0.38kWh/mi  Full Size SUVs 0.46 kWh/mi  The U.S. Bureau of Transportation Statistics estimates that in the U.S. During 2006, there were 1.683x10 12 mi driven in passenger cars and 1.089x10 12 mi driven in other 2-axle 4 wheeled vehicles (vans and SUVs) Per Mile Energy Cost: BTS Mileage Data:

 A rough assumption based on my own calculations of the data puts annual passenger car/SUV demand at TWh (1PWh)  Peak Generation Output of US Generators is approx 1.1TW, assuming maybe 900GW are in operation at all times, around 7900TWh could be generated annually.  The EIA also estimates the addition of around 20GW of generation capacity annually  Current demand averages around GW  In reality only some regions can currently cope with a heavy EV demand (Midwest has the capacity to currently support a full conversion to EVs, the West Coast does not) Power Generation Data from U.S. Energy Information Administration (EIA)

 Potential to sell electricity from an EV back to the grid during peak demand hours  A single EV can likely supply around 10kW  Also could be used as a source of emergency power in the event of a blackout. A nation of electric cars could potentially power the grid for up to 5 hours Image Source: University of Delaware

 A growing number of regions across the world are implementing modern technology to power distribution and metering  Smart meters can be used to provide time-specific electricity rates and cause non-essential power usage to be rescheduled to non-peak hours  Pricing changes or appliance-specific lockouts will influence  Example: Increased cost of running large appliances during peak load hours  Smart Meters will likely be essential to the implementation of a national EV fleet and V2G technology

Source B.B.S. Electronics

 Some regions and nations are actively installing smart meters  Ontario, Canada will have converted entirely over to smart meters by 2010  California and Texas also have large scale implementation of smart meters  Also used extensively in the UK and Australia Image Source: es.net/HHSC/assets/imag es/SmartMeter.jpg

 Types of Power Plants, Oglethorpe Power  Current Demand Outlook, California ISO  Blackouts, Virginia Department of Emergency Management  Pratt, et. al., Potential Impacts of High Penetration of Plug-in Hybrid Vehciles on the U.S. Power Grid, Pacific Northwest National Laboratory, June 2007,  U.S. Bureau of Transportation Statistics 2006 Vehicle Milage Data  Vehicle-To-Grid Technology, University of Delaware  Vehicle-To-Grid Technology Diagram, University of Delaware  Energy Information Administration Data