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Participation in demand response?

Participation in demand response?

Has anyone heard how Tesla is proposing to participate in demand response programs? These programs aren't very common yet, but my utility will soon be offering rebates for a connected charger that can be used to understand usage patterns, with the future goal of managing EV charging load.

It's usually with control of the charger, but as the Tesla chargers are "dumb" and the cars are smart (very), I assume it's thru the cars?

reed_lewis | February 8, 2019

In the car there is something called 'scheduled charging' which allows you to set the start time for charging.

Yodrak. | February 8, 2019

"my utility will soon be offering rebates for a connected charger that can be used to understand usage patterns, with the future goal of managing EV charging load."

The rebate is for a charger that you have or will obtain? Not a charger that is provided by, or specified by, the utility?

"It's usually with control of the charger, but as the Tesla chargers are "dumb" and the cars are smart (very), I assume it's thru the cars?"

I doubt it's through the car, but I don't know how the utility will monitor the usage pattern unless it installs something on the charger circuit. Some utilities have offered demand-response discounts for allowing the utility to cycle your central air conditioner off for a few minutes every hour during periods of high load, I was on such a program once. I don't know exactly how the utility did it, but it had to be a radio-controlled device inserted in the circuit that fed the A/C compressor.

mbirnie51 | February 9, 2019

The utility does it through the Smart Meter, which is controlled by radio frequency (RF). They can look at your demand load 120 times a second if need be, and "choke down" loads to agreed upon levels (brown outs) dependent on the area served. These meters are powerful tools the utilities haven't yet used to their fullest extent.
https://en.wikipedia.org/wiki/Smart_meter

Yodrak. | February 9, 2019

'Smart Meters', on their own, can only measure, record, report, the total house load. They cannot determine what individual loads are within the house. A device on, say, the dedicated circuit serving an EVSE would be required to know what the EVSE usage and usage pattern is. Such a device might be able to report the EVSE information back to the utility via the smart meter.

rxlawdude | February 9, 2019

The issue would be, if the "smarts" are in the EVSE, the Tesla may not continue charging if power is interrupted or reduced mid-charge.

Tesla's design puts the "smarts" in the internal charger.

TeslaTap.com | February 9, 2019

I've been using OhmConnect for several years now. They pay you to reduce power during peak times, and are paid by the utilities to help avoid turning on very expensive peaker plants. You usually get a day's warning of an upcoming "ohmhour" where they would like you to use less power. You can configure some items to automatically shut off for the hour, like the Tesla charging or devices connected to various plug-in WiFi switches. It's really fairly easy to set up, but you do need a SmartMeter and a utility that is working with them (Mostly California?). Here's a good starting point if you're interested: https://ohm.co/85d4bae

Now this is not the same as using your car battery to send power back to the grid (V2G) at peak times. Tesla's solution is to buy a PowerWall. The Tesla is not providing V2G ability, nor do most other EVs. I think the latest Leaf has such an option, although the extra battery usage seems like it would affect battery longevity and could cause warranty issues for the vehicle manufacturer.