EVs won’t impact FL power grid, but could affect specific neighborhoods

[Larry Chanin]

Electric Cars Won’t Have Impact On Florida Power Grid

The Florida Public Service Commission (FSPC), in its findings [PDF], concluded that “EV charging is expected to have a negligible effect on electricity consumption in Florida within the ten-year planning horizon” and that “EVs are also not currently expected to cause a significant increase in electric demand or contribute significantly to a need for new generation until well past 2021.” This looks to be good news indeed for the fledgling EV movement in this state, which currently is believed to be somewhere between 1,000 and 6,000 vehicles. This is based upon data provided by utilities and other organizations – apparently no government agency there tracks those figures formally.

Now what might possibly be an issue for Florida’s power grid in coming years is the so-called “clustering” of EVs in certain residential neighborhoods. Were this to happen, the FSPC said, its possible some equipment in select areas might need to be swapped out to handle, say, overnight demands of a larger number of EVs charging in a smaller area at the same time.

Please refer to the following thread to address the issue in the above highlighted paragraph.

Florida Power & Light (FPL) would like our assistance

Larry

 

[NigelM]

Also see this thread: Incoming-utility-cable-capacity-A-cautionary-tale

Note that in (at least) some parts of Florida the householder is responsible for the power cables from the street to the meter.

 

[Larry Chanin]

Also see this thread: Incoming-utility-cable-capacity-A-cautionary-tale

Note that in (at least) some parts of Florida the householder is responsible for the power cables from the street to the meter.

Thanks Nigel,

Of course Jim's situation was rather extreme having a 200 amp continuous load even before adding the 40 amps to charge his Model S. Nevertheless, it makes sense to let the power company know when you add significant loads such as a Model S.

Larry

 

[NigelM]

True, Jim's situation was extreme; however, we needed an upgrade of the incoming cable when we installed PV at our last house. That house was older and would maybe have struggled with 2 EV HPWCs and 2 ACs running at once if there was any other serious draw such as stove top or washer and dryer.

 

[ClearwaterBchSteve]

Our beach home is older as well. I still have a fuse box and need to replace it with a new curcuit-breaker panel and 200A service before I can permanently install a NEMA 14-50. For regular small daily commute, I use 120v but have rigged up a converter cable to allow me to use 240V @ 35A from my existing dryer plug if I need faster charging. The permanent 14-50 will be installed at the front of the garage to facilitate easy access for guest charging.

 

[Larry Chanin]

Here's an excerpt from the report referenced in the first posting.

Report of Electric Vehicle Charging

The chart shows that even a relatively large 100 kva transformer will only support a single 6.6 kW charger.

A NEMA 14-50 outlet behind a 50 amp breaker will draw about 9.6 KW.

A Roadster High Power Wall Connector will draw 16.8 KW.

A Model S High Power Wall Connector will draw 19.2 KW.

These are based on nominal voltages it is not uncommon to for the voltage to be plus or minus 5% so in the worst case a Model S HPWC could draw 20 KW.

Larry

 

[ClearwaterBchSteve]

That's very interesting data Larry. Being on the beach, we still have elevated power distribution and by looking at my rusted out transformer out front on the pole, I doubt I would be able to safely deploy an HPWC. Even after I get my fuse box replaced with with breakers and a new cable entry into the house installed, my 14-50 plus stove, oven, dryer, hot water, HVAC, etc. will most likely be the max for the infrastructure which supplies my house - all of those in use simultaneously would be > 200A.

 

[NigelM]

Mod note: Thread title updated by OP request.

 

[Larry Chanin]

That's very interesting data Larry. Being on the beach, we still have elevated power distribution and by looking at my rusted out transformer out front on the pole, I doubt I would be able to safely deploy an HPWC. Even after I get my fuse box replaced with with breakers and a new cable entry into the house installed, my 14-50 plus stove, oven, dryer, hot water, HVAC, etc. will most likely be the max for the infrastructure which supplies my house - all of those in use simultaneously would be > 200A.

Hi Steve,

For economic reasons power companies rely on load diversity to deliberately run their equipment above their nameplate ratings. This is based on the premise that most equipment has a duty cycle and doesn't run continuously, or all loads don't have coincident peak use. (A premise that was for the most part incorrect with respect to Jim's situation described in the link provided by Nigel in posting #2.)

If you haven't contacted your power company I would. If it is FPL you might start following the link I provided in the first posting. If there is any chance of you getting an HPWC I would let them know.

Larry

 

[ClearwaterBchSteve]

If there is any chance of you getting an HPWC I would let them know.

Larry

Larry, I have no plans to install an HPWC. I did not get twin chargers. Currently I alternate my makeshift temporary 14-50 with my dryer so I'm well under my limits if other high-draw devices in the house were pulling current. My concern is after a dedicated 14-50 is installed, the dryer could also be running at the same time along with other big items. When I get the fuse box replaced with a breaker panel, I will have 200A service which should be fine. Our house is not huge - only one HVAC system for example.

Thanks for your insight. Our power is supplied by Progress Energy.

Steve.

 

[Larry Chanin]

Larry, I have no plans to install an HPWC. I did not get twin chargers. Currently I alternate my makeshift temporary 14-50 with my dryer so I'm well under my limits if other high-draw devices in the house were pulling current. My concern is after a dedicated 14-50 is installed, the dryer could also be running at the same time along with other big items. When I get the fuse box replaced with a breaker panel, I will have 200A service which should be fine. Our house is not huge - only one HVAC system for example.

Thanks for your insight. Our power is supplied by Progress Energy.

Steve.

You'll still be drawing 40 continuous amps so I would call Progress Energy to let them know and see if they want to heavy-up that overhead transformer.

Larry