Do electric vehicles have demand response potential?

[kristopher]

Do electric vehicles have demand response potential?
By Bill Opalka
DECEMBER 18, 2013 | Share:

In office parks and residential garages, thousands of power plants sit idle, just waiting to relieve building owners and utilities of high power prices when peak demand stresses the electric generation and distribution systems.

That’s the vision and promise, at least, as electric vehicles enter the mass market and the infrastructure to support them is built out. As thousands of electric vehicles are expected to hit the street over the next few years, their batteries, which could collectively store thousands of kilowatts of electricity, could be tapped at a moment's notice.

The idea has been discussed at trade events and in renewable energy circles for years: charge batteries overnight when wind energy is generally plentiful and cheap, and draw that power back onto the grid the next afternoon when demand is high. This burgeoning technology is called vehicle-to-grid, or V2G, and the technical barriers appear to be limited.

Now, major automakers are testing the idea.

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More at http://www.utilitydive.com/news/do-electric-vehicles-have-demand-response-potential/205420/

[tularetom]

1. Let me get this straight

It's a hot sticky summer day. You get up go out to your garage, unplug your fully charged electric car and drive to work, where you plug it into a charger. While you're working the charge is restored. That afternoon, the temperature soars to triple digits and thousands of people crank up their air conditioners. As the power demand skyrockets, your battery is drained to help meet the demand. At five o'clock, when you get off work and get in your car to drive home, the fucking battery is dead. Somebody has used the cheap kilowatts that you purchased last night to avoid generating or buying more expensive kilowatts during a period of heavy demand.

I'd want some kind of compensation. Like the power company should have to pay me the avoided costs of the peak power.

[kristopher]

2. You don't have it straight

Your battery wouldn't get drained unless you want it to. You control the parameters involved in buying and selling so you'd set the lower bound. You could also schedule when you are willing to make the power available.

And yes, you do get paid and paid well; much more than the cost of avoided power.

The primary products provided by the pool of EV batteries are called "regulation services" and are high value exchanges where the power company extracts and deposits small sips of power very quickly to help stabilize the very high speed fluctuations encountered be shifting conditions in supply and demand.

Load shifting is something that will only become part of the picture when a much higher percentage of vehicles are participating. That will largely involve just automatically topping off the charge in the battery when wind and/or solar is producing excess capacity. To meet the demand for the traditional electric sector on an hour by hour basis, we'll need to build more renewable capacity than total or averaged demand numbers would suggest. But, by integrating the needs of the transportation sector, which is flexible because most vehicles are parked 95% of the time, we will obtain a system with far higher overall efficiency. You wouldn't get paid for this aspect like you would with regulation services, but it will help lower the cost of driving.

[tularetom]

3. Sounds intriguing

But when everybody has an electric car sitting in their garage hooked up to a charger every night, will the demand increase to the point where there is very little unit cost differential between overnight power and peak afternoon power? Won't the grid be working as hard at 3 am as it does at 3 pm?

I realize the more customers there are the smaller the margin needs to be, but it still seems to me there is a point of diminishing returns. The payback to the customer has to be enough to get people to participate.

And why do I even need an electric car to do this? I could simply just put a big ass battery in my garage and charge it up all night and then sell the juice back to the power company the next afternoon.

Very interesting topic. Think I'll learn more.

[kristopher]

4. If the present reliance on centralized thermal were to persist...

...ultimately the nighttime load would increase the cost, yes.

Do you participate in demand response programs in your home? I do. Our electric coop pays me $3/mo for allowing them to cycle my hot water heater when demand peaks are shooting costs up. I suffer no inconvenience, make a token amount, and everyone saves.

When EVs are dominate, the same sort of scenario will likely apply.

One difference will be that during the times that are now high demand, with variable generation there will often be excess production that will need to be soaked up so decreases in the peak costs will probably be correlated to some degree with increases in costs during the wee hours of the morning. Also, remember the fact that car's sit parked 95% of the time. The system will in many cases most likely have a substantial segment of vehicles charging while parked away from home during the day.

You might want to google "Kempton V2G". He developed the idea and is the one running the program mentioned in the OP at the University of Delaware which Honda just signed onto. He has his research posted at his UD (Go Blue Hens!) website.