Why is an EV\'s backup power less than it\'s driving power?...

[Commander Kinsey]

If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It\'s the same battery!

And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn\'t cost much, just something to make 400VDC into 240VAC. I\'d say more like 500 dollars.

 

[Peeler]

On Thu, 17 Nov 2022 09:27:37 -0000, Birdbrain Macaw (aka \"Commander Kinsey\",
\"James Wilkinson\", \"Steven Wanker\",\"Bruce Farquar\", \"Fred Johnson, etc.),
the pathological resident idiot and attention whore of all the uk ngs,
blathered again:

<FLUSH the subnormal sociopathic trolling attention whore\'s latest
attention-baiting sick bullshit unread again>

--
damduck-egg@yahoo.co.uk about Birdbrain Macaw\'s (now \"Commander Kinsey\" LOL)
trolling:
\"He is a well known attention seeking troll and every reply you
make feeds him.
Starts many threads most of which die quick as on the UK groups anyone
with sense Kill filed him ages ago which is why he now cross posts to
the US groups for a new audience.
This thread was unusual in that it derived and continued without him
to a large extent and his silly questioning is an attempt to get
noticed again.\"
MID: <be195d5jh0hktj054mvfu7ef9ap854mjdb@4ax.com>

--
ItsJoanNotJoann addressing Birdbrain Macaw\'s (now \"Commander Kinsey\" LOL):
\"You\'re an annoying troll and I\'m done with you and your
stupidity.\"
MID: <e39a6a7f-9677-4e78-a866-0590fe5bbc38@googlegroups.com>

--
AndyW addressing Birdbrain:
\"Troll or idiot?...
You have been presented with a viewpoint with information, reasoning,
historical cases, citations and references to back it up and wilfully
ignore all going back to your idea which has no supporting information.\"
MID: <KaToA.263621$g93.262397@fx10.am4>

 

[alan_m]

On 17/11/2022 09:27, Commander Kinsey wrote:

If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW?  It\'s the same battery!

The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

EVs require a larger battery because the owner can only drive 4 miles
for every kWh of battery (on a good day).

And why do people say it costs thousands of dollars to fit something to
do this?  Surely a 10kW invertor doesn\'t cost much, just something to
make 400VDC into 240VAC.  I\'d say more like 500 dollars.

Yep, a couple of quid for the battery, a few more quid for the casing,
employ some untrained monkey on minimum wage to fit it to the grid with
bell wire, a small inverter and a suicide lead to plug it back into a
convenient 3 pin socket when the backup is needed.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

 

[Fred Bloggs]

On Thursday, November 17, 2022 at 4:27:46 AM UTC-5, Commander Kinsey wrote:

If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It\'s the same battery!

And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn\'t cost much, just something to make 400VDC into 240VAC. I\'d say more like 500 dollars.

You need to learn the difference between energy and power. The 80kW is really 80kWh(hours), a measure of energy stored in the battery. The 10kW is a measure of power which is the rate of energy extraction from the battery, usually specified in kW, kilo-watts, thousands of Watts. There is no logical connection between the two ratings. The engineering requirements of the battery EV application determines that.

Here is an authoritative overview:
https://theconversation.com/can-my-electric-car-power-my-house-not-yet-for-most-drivers-but-vehicle-to-home-charging-is-coming-163332

News of a work in progress to make home backup routine with no special equipment required:
https://www.atlasevhub.com/weekly_digest/here-if-you-need-evs-as-backup-batteries/

The cost for equipment to do that is top dollar because they sell so few. There\'s no logical connection between present cost and a hypothetical mass produced product.

 

[Commander Kinsey]

On Thu, 17 Nov 2022 13:03:57 -0000, Fred Bloggs <bloggs.fredbloggs.fred@gmail.com> wrote:

On Thursday, November 17, 2022 at 4:27:46 AM UTC-5, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It\'s the same battery!

And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn\'t cost much, just something to make 400VDC into 240VAC. I\'d say more like 500 dollars.

You need to learn the difference between energy and power. The 80kW is really 80kWh(hours), a measure of energy stored in the battery. The 10kW is a measure of power which is the rate of energy extraction from the battery, usually specified in kW, kilo-watts, thousands of Watts. There is no logical connection between the two ratings. The engineering requirements of the battery EV application determines that.

Here is an authoritative overview:
https://theconversation.com/can-my-electric-car-power-my-house-not-yet-for-most-drivers-but-vehicle-to-home-charging-is-coming-163332

News of a work in progress to make home backup routine with no special equipment required:
https://www.atlasevhub.com/weekly_digest/here-if-you-need-evs-as-backup-batteries/

The cost for equipment to do that is top dollar because they sell so few. There\'s no logical connection between present cost and a hypothetical mass produced product.

Rewrite all that considering I know the difference between power and energy, I have a fucking physics degree. When I said 80kW I meant 80kW, not 80kWh. Do you seriously think a car motor only draws 10kW?

And that last link doesn\'t tell you how to do it, just sales waffle about Ford are getting to it.

Pretty easy really, you find the 400V battery wire and connect a convertor to it to make 240VAC.

 

[Commander Kinsey]

On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <junk@admac.myzen.co.uk> wrote:

On 17/11/2022 09:27, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW? It\'s the same battery!

The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

No, 10kW. I did not type an h.

EVs require a larger battery because the owner can only drive 4 miles
for every kWh of battery (on a good day).

And why do people say it costs thousands of dollars to fit something to
do this? Surely a 10kW invertor doesn\'t cost much, just something to
make 400VDC into 240VAC. I\'d say more like 500 dollars.

Yep, a couple of quid for the battery, a few more quid for the casing,
employ some untrained monkey on minimum wage to fit it to the grid with
bell wire, a small inverter and a suicide lead to plug it back into a
convenient 3 pin socket when the backup is needed.

What battery? The battery is already in the car. All you need is a convertor from 400VDC to 240VAC, and if you want it automated, a big contactor to switch to the car and back.

 

[Fred Bloggs]

On Thursday, November 17, 2022 at 8:17:58 AM UTC-5, Commander Kinsey wrote:

On Thu, 17 Nov 2022 13:03:57 -0000, Fred Bloggs <bloggs.fred...@gmail.com> wrote:

On Thursday, November 17, 2022 at 4:27:46 AM UTC-5, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It\'s the same battery!

And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn\'t cost much, just something to make 400VDC into 240VAC. I\'d say more like 500 dollars.

You need to learn the difference between energy and power. The 80kW is really 80kWh(hours), a measure of energy stored in the battery. The 10kW is a measure of power which is the rate of energy extraction from the battery, usually specified in kW, kilo-watts, thousands of Watts. There is no logical connection between the two ratings. The engineering requirements of the battery EV application determines that.

Here is an authoritative overview:
https://theconversation.com/can-my-electric-car-power-my-house-not-yet-for-most-drivers-but-vehicle-to-home-charging-is-coming-163332

News of a work in progress to make home backup routine with no special equipment required:
https://www.atlasevhub.com/weekly_digest/here-if-you-need-evs-as-backup-batteries/

The cost for equipment to do that is top dollar because they sell so few. There\'s no logical connection between present cost and a hypothetical mass produced product.
Rewrite all that considering I know the difference between power and energy, I have a fucking physics degree. When I said 80kW I meant 80kW, not 80kWh. Do you seriously think a car motor only draws 10kW?

Your so-called degree was a woefully inadequate preparation for dealing with reality if you have to ask such a stupid question.

And that last link doesn\'t tell you how to do it, just sales waffle about Ford are getting to it.

It wasn\'t a DIY project article. The responsible authorities don\'t want clueless yokels touching anything to do with it, so much so you may juts be liable to arrest if you do.

Pretty easy really, you find the 400V battery wire and connect a convertor to it to make 240VAC.

There are many more considerations to doing that you\'re unaware of.

 

[Martin Brown]

On 17/11/2022 13:19, Commander Kinsey wrote:

On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <junk@admac.myzen.co.uk> wrote:

On 17/11/2022 09:27, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW?  It\'s the same battery!

The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

No, 10kW.  I did not type an h.

10kW is a fairly reasonable figure for powering a home. Over engineering
it to do 20kW or 40kW continuous would not be good value for money.

It is enough for 2x 3kW fan heaters and a 3kW immersion heater with a
bit to spare for electric lighting and gadgets.

EVs require a larger battery because the owner can only drive 4 miles
for every kWh of battery (on a good day).

The other thing is that when an EV is moving at speed there is much
better cooling airflow around the vehicle and its batteries. Maximum
sustained power output will be reduced when the vehicle is stationary.

And why do people say it costs thousands of dollars to fit something to
do this?  Surely a 10kW invertor doesn\'t cost much, just something to
make 400VDC into 240VAC.  I\'d say more like 500 dollars.

Yep, a couple of quid for the battery, a few more quid for the casing,
employ some untrained monkey on minimum wage to fit it to the grid with
bell wire, a small inverter and a suicide lead to plug it back into a
convenient 3 pin socket when the backup is needed.

What battery?  The battery is already in the car.  All you need is a
convertor from 400VDC to 240VAC, and if you want it automated, a big
contactor to switch to the car and back.

A Tesla powerwall battery ~14kWh intended for home use has an inverter
that can only output about 7kW peak and 5kW continuous.

https://electrek.co/2021/04/22/tesla-increasing-powerwall-power-capacity/

--
Regards,
Martin Brown

 

[Peeler]

On Thu, 17 Nov 2022 09:54:42 +0000, anal_m, the notorious troll-feeding
senile retard, blathered again:


> The average usage of electricity per day for a UK household is less than

Back to sucking off the unwashed troll again, you sick senile pig?

 

[Peeler]

On Thu, 17 Nov 2022 13:39:36 +0000, Martin Brown, another troll-feeding
senile shithead, bullshitted yet again:


> 10kW is a fairly reasonable figure for powering a home. Over engineering

Yet another useless sick senile pig who couldn\'t resist sucking off the
unwashed troll yet again! LOL

 

[John Larkin]

On Thu, 17 Nov 2022 05:03:57 -0800 (PST), Fred Bloggs
<bloggs.fredbloggs.fred@gmail.com> wrote:

On Thursday, November 17, 2022 at 4:27:46 AM UTC-5, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It\'s the same battery!

And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn\'t cost much, just something to make 400VDC into 240VAC. I\'d say more like 500 dollars.

You need to learn the difference between energy and power. The 80kW is really 80kWh(hours), a measure of energy stored in the battery. The 10kW is a measure of power which is the rate of energy extraction from the battery, usually specified in kW, kilo-watts, thousands of Watts. There is no logical connection between the two ratings. The engineering requirements of the battery EV application determines that.

He clearly said that the battery can deliver 80 KW of power. No 80 KWH
car is going to be limited to 10 KW into the motors. Ecars are all
about acceleration.

You need to learn how to read and how to discuss.

 

[Ricky]

On Thursday, November 17, 2022 at 4:27:46 AM UTC-5, Commander Kinsey wrote:

If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It\'s the same battery!

And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn\'t cost much, just something to make 400VDC into 240VAC. I\'d say more like 500 dollars.

I don\'t know who you are talking to. Many people talk about stuff they don\'t actually know much about. An EVSE which does zero energy conversion, costs around $400 for 5 kW handling capability. 10 kW is around 42 amps. So I can see a 10 kW inverter being much more expensive than $500. If you think you can make and sell them at a profit, for $500, you need to go into that business!

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[Ricky]

On Thursday, November 17, 2022 at 4:54:49 AM UTC-5, alan_m wrote:

On 17/11/2022 09:27, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW? It\'s the same battery!
The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

That doesn\'t necessarily follow. If you run an electric stove, and electric water heater and a heat pump at the same time, you can easily overload a 10 kW power source and still not reach 10 kWh.

--

Rick C.

+ Get 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209

 

[Ricky]

On Thursday, November 17, 2022 at 8:39:52 AM UTC-5, Martin Brown wrote:

On 17/11/2022 13:19, Commander Kinsey wrote:
On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <ju...@admac.myzen.co.uk> wrote:

On 17/11/2022 09:27, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW? It\'s the same battery!

The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

No, 10kW. I did not type an h.
10kW is a fairly reasonable figure for powering a home. Over engineering
it to do 20kW or 40kW continuous would not be good value for money.

It is enough for 2x 3kW fan heaters and a 3kW immersion heater with a
bit to spare for electric lighting and gadgets.
EVs require a larger battery because the owner can only drive 4 miles
for every kWh of battery (on a good day).
The other thing is that when an EV is moving at speed there is much
better cooling airflow around the vehicle and its batteries. Maximum
sustained power output will be reduced when the vehicle is stationary.

You might think that applies to charging as well, which is typically done with the car stationary. Yet charging is done at power levels much higher than the typical 15-20 kW a car uses. Even on steep upgrades or when passing it\'s seldom my car uses over 150 kW. On the other hand, it charges at rates up to 175 kW, sustained, while parked. I wonder if it\'s some sort of charging miracle? Oh, wait, they use fans.

And why do people say it costs thousands of dollars to fit something to
do this? Surely a 10kW invertor doesn\'t cost much, just something to
make 400VDC into 240VAC. I\'d say more like 500 dollars.

Yep, a couple of quid for the battery, a few more quid for the casing,
employ some untrained monkey on minimum wage to fit it to the grid with
bell wire, a small inverter and a suicide lead to plug it back into a
convenient 3 pin socket when the backup is needed.

What battery? The battery is already in the car. All you need is a
convertor from 400VDC to 240VAC, and if you want it automated, a big
contactor to switch to the car and back.
A Tesla powerwall battery ~14kWh intended for home use has an inverter
that can only output about 7kW peak and 5kW continuous.

https://electrek.co/2021/04/22/tesla-increasing-powerwall-power-capacity/

Yeah, they are a bit limited too. Try using one as your primary backup. When it kicks in, your electric use is suddenly limited.

I wonder if they divide the breaker panel into backed up and not backed up?

--

Rick C.

-- Get 1,000 miles of free Supercharging
-- Tesla referral code - https://ts.la/richard11209

 

[Martin Rid]

Martin Brown <\'\'\'newspam\'\'\'@nonad.co.uk> Wrote in message:r

On 17/11/2022 13:19, Commander Kinsey wrote:> On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <junk@admac.myzen.co.uk> wrote:> >> On 17/11/2022 09:27, Commander Kinsey wrote:>>> If an EV has an output power of say 80kW to drive the motors when>>> driving, why is the backup power (to power your house in a power outage)>>> only about 10kW? It\'s the same battery!>>>> The average usage of electricity per day for a UK household is less than>> 10kWh so a 10kWh backup battery will supply power for a day or more in>> the event of a power cut.> > No, 10kW. I did not type an h.10kW is a fairly reasonable figure for powering a home. Over engineering it to do 20kW or 40kW continuous would not be good value for money.It is enough for 2x 3kW fan heaters and a 3kW immersion heater with a bit to spare for electric lighting and gadgets.>> EVs require a larger battery because the owner can only drive 4 miles>> for every kWh of battery (on a good day).The other thing is that when an EV is moving at speed there is much better cooling airflow around the vehicle and its batteries. Maximum sustained power output will be reduced when the vehicle is stationary.>>> And why do people say it costs thousands o
f dollars to fit something to>>> do this? Surely a 10kW invertor doesn\'t cost much, just something to>>> make 400VDC into 240VAC. I\'d say more like 500 dollars.>>>> Yep, a couple of quid for the battery, a few more quid for the casing,>> employ some untrained monkey on minimum wage to fit it to the grid with>> bell wire, a small inverter and a suicide lead to plug it back into a>> convenient 3 pin socket when the backup is needed.> > What battery? The battery is already in the car. All you need is a > convertor from 400VDC to 240VAC, and if you want it automated, a big > contactor to switch to the car and back.A Tesla powerwall battery ~14kWh intended for home use has an inverter that can only output about 7kW peak and 5kW continuous.https://electrek.co/2021/04/22/tesla-increasing-powerwall-power-capacity/-- Regards,Martin Brown

Most homes only have a 100A service. Maybe 200A for newer homes,
so you would need a 100A limit to be on the safe side. One size
fits all.

Cheers
--


----Android NewsGroup Reader----
https://piaohong.s3-us-west-2.amazonaws.com/usenet/index.html

 

[Joe Gwinn]

On Thu, 17 Nov 2022 13:39:36 +0000, Martin Brown
<\'\'\'newspam\'\'\'@nonad.co.uk> wrote:

On 17/11/2022 13:19, Commander Kinsey wrote:
On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <junk@admac.myzen.co.uk> wrote:

On 17/11/2022 09:27, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW?  It\'s the same battery!

The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

No, 10kW.  I did not type an h.

10kW is a fairly reasonable figure for powering a home. Over engineering
it to do 20kW or 40kW continuous would not be good value for money.

In the UK, perhaps. In the US, lots of homes have gone to 100-amp 220
Vac split phase, or 22 KW. Some have twice that.

My house has 100 amp service. But we have a gas stove and water
heater, and oil heat. No electric heat. My shop runs off 220 Vac,
but the big machines are only used intermittently, but will need a lot
of power when doing something heavy.

Most appliances (including air conditioners) are 120 Vac and 15 or 20
amps. Things like clothes dryers are 220 Vac. Many people have
electric water heaters. also 220 Vac.


Joe Gwinn

 

[Fred Bloggs]

On Thursday, November 17, 2022 at 10:30:31 AM UTC-5, John Larkin wrote:

On Thu, 17 Nov 2022 05:03:57 -0800 (PST), Fred Bloggs
bloggs.fred...@gmail.com> wrote:

On Thursday, November 17, 2022 at 4:27:46 AM UTC-5, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It\'s the same battery!

And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn\'t cost much, just something to make 400VDC into 240VAC. I\'d say more like 500 dollars.

You need to learn the difference between energy and power. The 80kW is really 80kWh(hours), a measure of energy stored in the battery. The 10kW is a measure of power which is the rate of energy extraction from the battery, usually specified in kW, kilo-watts, thousands of Watts. There is no logical connection between the two ratings. The engineering requirements of the battery EV application determines that.

He clearly said that the battery can deliver 80 KW of power. No 80 KWH
car is going to be limited to 10 KW into the motors. Ecars are all
about acceleration.

That 80kW is quoted quite often as the battery capacity when they mean 80kWh of course. Without that as his fundamental misunderstanding, the question is senseless.

I\'ll go out on a limb and say nearly all the battery energy goes to breaking air resistance at constant speed. There\'s no getting around the basic requirement of having to supply torque at speed to the drive shaft to overcome the square law wind resistance. With the exception of some arrested development types, most of the relatively affluent owners should be past the thrill driving stage of their lives.

You need to learn how to read and how to discuss.

 

[Fred Bloggs]

On Thursday, November 17, 2022 at 11:32:05 AM UTC-5, Martin Rid wrote:

Martin Brown <\'\'\'newspam\'\'\'@nonad.co.uk> Wrote in message:r
On 17/11/2022 13:19, Commander Kinsey wrote:> On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <ju...@admac.myzen.co.uk> wrote:> >> On 17/11/2022 09:27, Commander Kinsey wrote:>>> If an EV has an output power of say 80kW to drive the motors when>>> driving, why is the backup power (to power your house in a power outage)>>> only about 10kW? It\'s the same battery!>>>> The average usage of electricity per day for a UK household is less than>> 10kWh so a 10kWh backup battery will supply power for a day or more in>> the event of a power cut.> > No, 10kW. I did not type an h.10kW is a fairly reasonable figure for powering a home. Over engineering it to do 20kW or 40kW continuous would not be good value for money.It is enough for 2x 3kW fan heaters and a 3kW immersion heater with a bit to spare for electric lighting and gadgets.>> EVs require a larger battery because the owner can only drive 4 miles>> for every kWh of battery (on a good day).The other thing is that when an EV is moving at speed there is much better cooling airflow around the vehicle and its batteries. Maximum sustained power output will be reduced when the vehicle is stationary.>>> And why do people say it costs thousands of dollars to fit something to>>> do this? Surely a 10kW invertor doesn\'t cost much, just something to>>> make 400VDC into 240VAC. I\'d say more like 500 dollars.>>>> Yep, a couple of quid for the battery, a few more quid for the casing,>> employ some untrained monkey on minimum wage to fit it to the grid with>> bell wire, a small inverter and a suicide lead to plug it back into a>> convenient 3 pin socket when the backup is needed.> > What battery? The battery is already in the car. All you need is a > convertor from 400VDC to 240VAC, and if you want it automated, a big > contactor to switch to the car and back.A Tesla powerwall battery ~14kWh intended for home use has an inverter that can only output about 7kW peak and 5kW continuous.https://electrek.co/2021/04/22/tesla-increasing-powerwall-power-capacity/-- Regards,Martin Brown

Most homes only have a 100A service. Maybe 200A for newer homes,
so you would need a 100A limit to be on the safe side. One size
fits all.

Cheers
--


----Android NewsGroup Reader----
https://piaohong.s3-us-west-2.amazonaws.com/usenet/index.html

You don\'t need to limit anything. The inverter just worries about protecting itself with suitable size and type of circuit breaker. If the user overloads and trips it, that\'s their problem, they need to start disconnecting loads.

 

[Ricky]

On Thursday, November 17, 2022 at 11:59:31 AM UTC-5, Joe Gwinn wrote:

On Thu, 17 Nov 2022 13:39:36 +0000, Martin Brown
\'\'\'newspam\'\'\'@nonad.co.uk> wrote:

On 17/11/2022 13:19, Commander Kinsey wrote:
On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <ju...@admac.myzen.co.uk> wrote:

On 17/11/2022 09:27, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW? It\'s the same battery!

The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

No, 10kW. I did not type an h.

10kW is a fairly reasonable figure for powering a home. Over engineering
it to do 20kW or 40kW continuous would not be good value for money.
In the UK, perhaps. In the US, lots of homes have gone to 100-amp 220
Vac split phase, or 22 KW. Some have twice that.

No home in the US have gone to 100-amp, 220VAC split phase. The nominal voltage in the US is 240V. I expect very few homes in the US have been built with 100 amp service in the last 50 years. In the 70s, there was a big push to use more electric appliances, including electric radiant heat! You aren\'t getting that with 100 amp service.

My house has 100 amp service. But we have a gas stove and water
heater, and oil heat. No electric heat. My shop runs off 220 Vac,
but the big machines are only used intermittently, but will need a lot
of power when doing something heavy.

Do you have a 240V to 220V transformer? If not, you have excessive voltage drop coming to your house and should ask the power company to fix that.

Most appliances (including air conditioners) are 120 Vac and 15 or 20
amps. Things like clothes dryers are 220 Vac. Many people have
electric water heaters. also 220 Vac.

If you have 120V on the low voltage outlets, how do you get 220V on the high voltage circuits? Is your line not balanced with one at 120V and the other at 100V?

--

Rick C.

-+ Get 1,000 miles of free Supercharging
-+ Tesla referral code - https://ts.la/richard11209

 

[Fred Bloggs]

On Thursday, November 17, 2022 at 11:59:31 AM UTC-5, Joe Gwinn wrote:

On Thu, 17 Nov 2022 13:39:36 +0000, Martin Brown
\'\'\'newspam\'\'\'@nonad.co.uk> wrote:

On 17/11/2022 13:19, Commander Kinsey wrote:
On Thu, 17 Nov 2022 09:54:42 -0000, alan_m <ju...@admac.myzen.co.uk> wrote:

On 17/11/2022 09:27, Commander Kinsey wrote:
If an EV has an output power of say 80kW to drive the motors when
driving, why is the backup power (to power your house in a power outage)
only about 10kW? It\'s the same battery!

The average usage of electricity per day for a UK household is less than
10kWh so a 10kWh backup battery will supply power for a day or more in
the event of a power cut.

No, 10kW. I did not type an h.

10kW is a fairly reasonable figure for powering a home. Over engineering
it to do 20kW or 40kW continuous would not be good value for money.
In the UK, perhaps. In the US, lots of homes have gone to 100-amp 220
Vac split phase, or 22 KW. Some have twice that.

My house has 100 amp service. But we have a gas stove and water
heater, and oil heat. No electric heat. My shop runs off 220 Vac,
but the big machines are only used intermittently, but will need a lot
of power when doing something heavy.

Most appliances (including air conditioners) are 120 Vac and 15 or 20
amps. Things like clothes dryers are 220 Vac. Many people have
electric water heaters. also 220 Vac.

This table is pretty close, except for some things like their ridiculously low estimate of an electric range. Go down the list and add them up. Some things need to be permanently shut off/ not used in backup mode.

https://unboundsolar.com/solar-information/power-table

Joe Gwinn