Friday, 3 February 2012

PJM and GM run trial charging from renewable energy

Here's a cross-post from Glen Estill's blog.  It describes yet another way that Ontario could manage electrical demand during times when we have an abundance of renewal energy.

Glen Estill's wind-blog
January 29, 2012

PJM – the regional transmission operator for Pennsylvania, New Jersey and Maryland has an interesting trial underway with charging of the Chevy Volt, the plug in hybrid from General Motors.

The system operator will monitor the output from the region’s renewable energy sources, and when surplus is available, will send a signal to General Motors. General Motors will then relay the signal on to the Chevy Volts connected to the system via their On Star system, and tell those vehicles to beginning charging their batteries. It shows forward thinking both by PJM and GM.

I like the fact that it is using existing technology – the On Star system, that is standard with the Volt. This makes such a system insanely cheap to implement.

Of course if the system operator can send signals for when renewable energy is available, they could act on almost any parameter, such as when power is in surplus from any source, or when power is cheapest. The renewable energy aspect of this is mainly for public relations – system operators need more tools to allow them to manage both times of surplus and shortage of power, and this is a powerful and very low cost tool.

PJM is showing great foresight in looking into this now. There are still some unknowns about electric cars. How many will there be? How much power can the average one take? How many cars are plugged in when the signal is sent? Gathering information now will help them greatly as the number of electric cars proliferates. They will also learn how to quickly implement systems, and standardize software interfaces to accommodate new electric car makes and models.

The Ontario IESO has talked about an emerging problem of surplus baseload generation (SBG). This is when generation in the province exceeds demand (including exports). As we bring on more inflexible refurbished nuclear plants, that can’t be shut down easily, the problem is likely to get worse. Of course, if you can shift demand to times of SBG, you could solve the problem. Using electric cars is just one solution, but one that will become more important as the electric car fleet increases in size.

The Chevy Volt stores 16 kWh fully charged. If an average Volt requires 10 kWh to be topped up at the end of the day, then 100,000 Volts would require 1 million kWh, or 1000 MW of generation for an hour. This is equal to 70% of Ontario’s wind fleet, or equal to the output of 2 of the Pickering units. This is not a trivial amount. And 100,000 Chevy Volts is only a little over 1% of the vehicle fleet in Ontario, and less than half the current fleet of hybrid vehicles. In addition to the Volt, there is the Nissan Leaf, which stores 24 kWh, and another 10 plug in electric vehicles coming to the market in the next year or two. 1% may be conservative.

The bottom line is electric cars offer interesting potential to buffer times of surplus power on a system. If this is added to using dams to store water when surplus generation exists, either in Ontario or neighbouring hydraulic based Quebec and Manitoba, or switching on hot water heaters, and other innovative load shifting techniques, the problem of SBG can be addressed. It would be good if the IESO would begin their own trials with GM.

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