Re: [EVDL] V2G for my grid tied solar? (constant current charging) Optimizers - NOT!)

[Robert Bruninga via EV]

Avoid "Optimizers" like the plague!

They generate horrendous radio frquency interference, blocking AM and
Shortwave and Ham raido HF communication for blocks.  It cannot be fixed
without removing every panel and re-doiong all the HV wiring into twisted
pairs and having RFI chokes on every wire going ito and out of them.  The
reception is only tollerable.

Furthermore, you can now see the diadavantages of optimizers and
microinverters in grid down situations for the DIY kinda person.

Sorry...

Bob

On Mon, Sep 2, 2019 at 2:54 PM Jay Summet via EV  wrote:

> Related question:
>
> I have solar panels, but they each have a DC optimizer on them
> (basically does MPPT and production level measurement on a per panel
> basis, but sends DC down to the wall mounted inverter).
>
> When the grid is down, the (Solar Edge SE 10KW) inverter shuts down, and
> the DC optimizer (P320 Solar Edge Optimizers) go into a "standby" mode
> where they each produce exactly 1 volt. This limits the DC voltage on
> the DC lines from the roof to 18 volts (18 panels/optimizers per line).
> [They wait for an OK from the inverter before they power back up to full
> voltage.]
>
> My question: Anybody know how much current (if any?) they provide when
> in this standby state? 18V is enough to recharge a 12v system, but if
> the optimizers are not producing any real current, it's probably useless.
>
> The spec sheet says 1.0 +/- 0.1 volt DC output in Standby mode, but does
> not specify anything about the maximum amps in this state.  I would
> assume they turn the amp output down quite a bit as well, as this is
> designed to make the solar wiring "safe" in the event of power shutdown.
>
> Just wondering if anybody had measured the actual current available.
>
> Jay
>
>
>
>
>
>
>
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Re: [EVDL] V2G for my grid tied solar? (constant current charging)

[Jay Summet via EV]

Related question:

I have solar panels, but they each have a DC optimizer on them 
(basically does MPPT and production level measurement on a per panel 
basis, but sends DC down to the wall mounted inverter).


When the grid is down, the (Solar Edge SE 10KW) inverter shuts down, and 
the DC optimizer (P320 Solar Edge Optimizers) go into a "standby" mode 
where they each produce exactly 1 volt. This limits the DC voltage on 
the DC lines from the roof to 18 volts (18 panels/optimizers per line). 
[They wait for an OK from the inverter before they power back up to full 
voltage.]


My question: Anybody know how much current (if any?) they provide when 
in this standby state? 18V is enough to recharge a 12v system, but if 
the optimizers are not producing any real current, it's probably useless.


The spec sheet says 1.0 +/- 0.1 volt DC output in Standby mode, but does 
not specify anything about the maximum amps in this state.  I would 
assume they turn the amp output down quite a bit as well, as this is 
designed to make the solar wiring "safe" in the event of power shutdown.


Just wondering if anybody had measured the actual current available.

Jay







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Re: [EVDL] V2G for my grid tied solar? (constant current charging)

[Lee Hart via EV]

Peri Hartman via EV wrote:

Well, if it's current that varies, it makes sense. Maybe I
misunderstood, but your prior post says "any voltage from 0 up to...".


Bob is right; PV panels do behave somewhat like a current source. If you 
look at a graph of voltage vs. current at some fixed light level, it 
looks roughly like a quarter of a circle, centered on 0v, 0a. Here's a 
crude ASCII graph (view with a fixed-width font).


voltage
max X X
 || . . X <--peak power point
 || . . . X
0v. . . . X
amp 0 . . max

The light level changes both the max voltage and max current it can 
deliver. Peak power is delivered somewhere in the middle (MPPT 
algorithms vary the load on the PV panels to find this point).


Near its max voltage, the PV panel act somewhat like a voltage source. 
Thus, a 15v max panel can be connected directly to a 12v battery and 
won't overcharge it. Above this, you'd need something to limit the peak 
voltage. The PV voltage varies with light, so connecting it directly to 
a battery also means it won't get maximum power, and won't charge at all 
when the light level is lower.


Near its max current, the PV panel acts more like a current source. That 
means the current barely changes despite the voltage it is delivering. A 
450v PV panel would charge a 6v, 12v, 24v, or 48v pack all at about the 
same current. The current depends on light level. If the PV panel's 
short-circuit current is 4a, then it would charge any of these batteries 
at about 4a.


Again, you won't get anywhere near the peak power that the PV panels can 
deliver. And, you can't leave it connected or it will overcharge the 
batteries to death.


DC requires DC-rated switches, contactors, circuit breakers, and 
connectors. Above 30v or so, arcing becomes serious! Make *sure* the 
parts you are using are rated for the peak voltage and current!


They're not common, but it's not too hard to get parts that can handle 
450v DC at 4 amps. They typically have arc ladders, magnetic blowouts, 
or exceptionally large contact spacings. Kilovac makes some contactors, 
and Anderson Power Products has some Power-Pole connectors that can do 
it. Schrack relays usually have DC ratings on their data sheets, though 
you have to connected multiple poles in series to reach 450v DC (for 
example, two 250vdc, or four 150vdc contacts).


Be careful!

--
I have no special talents. I am only passionately curious.
-- Albert Einstein
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
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Re: [EVDL] V2G for my grid tied solar? (constant current charging)

[Robert Bruninga via EV]

Solar cells are current sources.  Their current is linear with light level
not the voltage.  The voltage is between about 0.55 volts per cell under no
load, down to about 0.45 volts under max load.  Drawing any more current
and the voltage rapidly goes to zero.  So a 60 cell common panel has an
open circuit voltage of 36volts or more and a full load voltage around 30
volts.  The IV curve is rectangular.  It is a bit like a voltage source for
light loads up to the peak power point, then it becomes a current source at
near constant current at higher loads as the voltage drops to zero.

And since the height (current) of the IV curve varies directly with light
level, then the peak power point is always changing and why MPPT trackers
do a better job at getting max power under a variety of lighting levels.
Google for PV IV curve

Bob



On Mon, Sep 2, 2019 at 10:50 AM Peri Hartman via EV 
wrote:

> Interesting, but I'm not sure I completely follow.
>
> Batteries, particularly Li ion, don't have linear voltage. They stay
> pretty much near their nominal voltage until nearly discharged and vice
> versa. I don't know the voltage curve for solar panels but I'll make an
> assumption it is more or less linear with the amount of light.  Given
> that, doesn't that mean that the panels will charge the battery only
> part of the time, when there is strong light ? Is that an adequate
> percent of the time ? Also, you have to monitor by hand, right ? Once
> the battery is up to max voltage, you need to disconnect or you will
> destroy the cells.
>
> Peri
>
> -- Original Message --
> From: "Robert Bruninga via EV" 
> To: "Electric Vehicle Discussion List" 
> Cc: "Robert Bruninga" 
> Sent: 02-Sep-19 7:20:27 AM
> Subject: Re: [EVDL] V2G for my grid tied solar? (constant current
> charging)
>
> >One final point about grid down charging (under a must have armagedon
> >scenario): (And only for those fully experienced in HVDC)
> >
> >  Remember that Solar panels are current limited power sources.  This
> means
> >It will provide its rated current at ANY voltage from 0 (short circuit) up
> >to its nominal operating voltage.
> >
> >This means I can just clip the 450 volts DC straight from any one of my 3
> >kW solar panel arrays and run it straight to a 12, 24, 48, or 72 volt
> >battery (or 240v prius) directly for a temoporary 7 to 9 amp charge. WHICH
> >ONE MUST MONITOR to know when to disconnect.  AND one must have arc-flash
> >eye protection because you will draw a lightening bright arc flash when
> you
> >disconnect (and or while connecting if the connection is not made
> >cleanly).  But you will get a 7 amp charge (in my case of older panels).
> >New 300W panels can give 9 amps.
> >
> >(You MUST disconnect from your GT inverter of course,.  You do not want
> any
> >capacitor holding the 450v or it is no longer a perfect current limited
> >source).
> >
> >And with 6 such separate panel arrays, I can combine the currents at the
> >battery to give me up to 42 amps at 12, 24, 48, 72... (or 240) volts if
> >needed.  But again MUST human monitor in real time.  It is not easy to
> >throw together a charge regulating circuit to open a relay when the charge
> >is complete as agaiin, you must use very expensive HVDC contactors and or
> >snubbers.  And by th time you do all that , you could have build a more
> >direct DC/DC converter.
> >
> >So again, this is just an emergency data point.  For example, while
> drawing
> >1 kW (80 amps) from my prius 12v battery to power the house, all I need at
> >240v DC is 4 amps from the solar array.  And in my 14 year old Priuses I
> >know exactly where the HV battery posts are and can connect there and am
> >happy to take the risk.  Not sure I wouild take the risk for the 350v
> >battry in the newer Volt (which could give me 2 kW from its DC/DC
> >converter)..
> >
> >Anyway. just thought I would mention it.  Oh, and the open circuit voltage
> >of the solar arrays on the brightest and coldest day can approach 600
> >volts, not the 450 nominal load point...  But again, just short that 600
> >volts with an ampmeter and you will still see only the 7, 8 or 9 amp
> >current from your arry even at zero volts.  Just protect your eyes from
> the
> >arc flash when you disconnect (oh, it will also vaporize pieces off your
> >clip leads too each time), and it can just melt the tip off the copper
> wire
> >to molten copper and catch fire to the insulation and anything else within
> >a few inches if you let the arc continue...)..
> >
> >NOT SOMETHING TO PLAY AROUND WITH!
> >
> >But you can charge an

Re: [EVDL] V2G for my grid tied solar? (constant current charging)

[Peri Hartman via EV]

Well, if it's current that varies, it makes sense. Maybe I 
misunderstood, but your prior post says "any voltage from 0 up to...".


Peri

-- Original Message --
From: "Robert Bruninga" 
To: "Peri Hartman" ; "Electric Vehicle Discussion 
List" 

Sent: 02-Sep-19 8:31:26 AM
Subject: Re: [EVDL] V2G for my grid tied solar? (constant current 
charging)


Solar cells are current sources.  Their current is linear with light 
level not the voltage.  The voltage is between about 0.55 volts per 
cell under no load, down to about 0.45 volts under max load.  Drawing 
any more current and the voltage rapidly goes to zero.  So a 60 cell 
common panel has an open circuit voltage of 36volts or more and a full 
load voltage around 30 volts.  The IV curve is rectangular.  It is a 
bit like a voltage source for light loads up to the peak power point, 
then it becomes a current source at near constant current at higher 
loads as the voltage drops to zero.


And since the height (current) of the IV curve varies directly with 
light level, then the peak power point is always changing and why MPPT 
trackers do a better job at getting max power under a variety of 
lighting levels.  Google for PV IV curve


Bob



On Mon, Sep 2, 2019 at 10:50 AM Peri Hartman via EV  
wrote:

Interesting, but I'm not sure I completely follow.

Batteries, particularly Li ion, don't have linear voltage. They stay
pretty much near their nominal voltage until nearly discharged and 
vice
versa. I don't know the voltage curve for solar panels but I'll make 
an

assumption it is more or less linear with the amount of light.  Given
that, doesn't that mean that the panels will charge the battery only
part of the time, when there is strong light ? Is that an adequate
percent of the time ? Also, you have to monitor by hand, right ? Once
the battery is up to max voltage, you need to disconnect or you will
destroy the cells.

Peri

-- Original Message --
From: "Robert Bruninga via EV" 
To: "Electric Vehicle Discussion List" 
Cc: "Robert Bruninga" 
Sent: 02-Sep-19 7:20:27 AM
Subject: Re: [EVDL] V2G for my grid tied solar? (constant current
charging)

>One final point about grid down charging (under a must have armagedon
>scenario): (And only for those fully experienced in HVDC)
>
>  Remember that Solar panels are current limited power sources.  This 
means
>It will provide its rated current at ANY voltage from 0 (short 
circuit) up

>to its nominal operating voltage.
>
>This means I can just clip the 450 volts DC straight from any one of 
my 3

>kW solar panel arrays and run it straight to a 12, 24, 48, or 72 volt
>battery (or 240v prius) directly for a temoporary 7 to 9 amp charge. 
WHICH
>ONE MUST MONITOR to know when to disconnect.  AND one must have 
arc-flash
>eye protection because you will draw a lightening bright arc flash 
when you

>disconnect (and or while connecting if the connection is not made
>cleanly).  But you will get a 7 amp charge (in my case of older 
panels).

>New 300W panels can give 9 amps.
>
>(You MUST disconnect from your GT inverter of course,.  You do not 
want any
>capacitor holding the 450v or it is no longer a perfect current 
limited

>source).
>
>And with 6 such separate panel arrays, I can combine the currents at 
the
>battery to give me up to 42 amps at 12, 24, 48, 72... (or 240) volts 
if
>needed.  But again MUST human monitor in real time.  It is not easy 
to
>throw together a charge regulating circuit to open a relay when the 
charge
>is complete as agaiin, you must use very expensive HVDC contactors 
and or
>snubbers.  And by th time you do all that , you could have build a 
more

>direct DC/DC converter.
>
>So again, this is just an emergency data point.  For example, while 
drawing
>1 kW (80 amps) from my prius 12v battery to power the house, all I 
need at
>240v DC is 4 amps from the solar array.  And in my 14 year old 
Priuses I
>know exactly where the HV battery posts are and can connect there and 
am

>happy to take the risk.  Not sure I wouild take the risk for the 350v
>battry in the newer Volt (which could give me 2 kW from its DC/DC
>converter)..
>
>Anyway. just thought I would mention it.  Oh, and the open circuit 
voltage

>of the solar arrays on the brightest and coldest day can approach 600
>volts, not the 450 nominal load point...  But again, just short that 
600

>volts with an ampmeter and you will still see only the 7, 8 or 9 amp
>current from your arry even at zero volts.  Just protect your eyes 
from the
>arc flash when you disconnect (oh, it will also vaporize pieces off 
your
>clip leads too each time), and it can just melt the tip off the 
copper wire
>to molten copper and catch fire to the insulation and anything else 
within

>a few inches if you let the arc continue...)..
>

Re: [EVDL] V2G for my grid tied solar? (constant current charging)

[Peri Hartman via EV]

Interesting, but I'm not sure I completely follow.

Batteries, particularly Li ion, don't have linear voltage. They stay 
pretty much near their nominal voltage until nearly discharged and vice 
versa. I don't know the voltage curve for solar panels but I'll make an 
assumption it is more or less linear with the amount of light.  Given 
that, doesn't that mean that the panels will charge the battery only 
part of the time, when there is strong light ? Is that an adequate 
percent of the time ? Also, you have to monitor by hand, right ? Once 
the battery is up to max voltage, you need to disconnect or you will 
destroy the cells.


Peri

-- Original Message --
From: "Robert Bruninga via EV" 
To: "Electric Vehicle Discussion List" 
Cc: "Robert Bruninga" 
Sent: 02-Sep-19 7:20:27 AM
Subject: Re: [EVDL] V2G for my grid tied solar? (constant current 
charging)



One final point about grid down charging (under a must have armagedon
scenario): (And only for those fully experienced in HVDC)

 Remember that Solar panels are current limited power sources.  This means
It will provide its rated current at ANY voltage from 0 (short circuit) up
to its nominal operating voltage.

This means I can just clip the 450 volts DC straight from any one of my 3
kW solar panel arrays and run it straight to a 12, 24, 48, or 72 volt
battery (or 240v prius) directly for a temoporary 7 to 9 amp charge. WHICH
ONE MUST MONITOR to know when to disconnect.  AND one must have arc-flash
eye protection because you will draw a lightening bright arc flash when you
disconnect (and or while connecting if the connection is not made
cleanly).  But you will get a 7 amp charge (in my case of older panels).
New 300W panels can give 9 amps.

(You MUST disconnect from your GT inverter of course,.  You do not want any
capacitor holding the 450v or it is no longer a perfect current limited
source).

And with 6 such separate panel arrays, I can combine the currents at the
battery to give me up to 42 amps at 12, 24, 48, 72... (or 240) volts if
needed.  But again MUST human monitor in real time.  It is not easy to
throw together a charge regulating circuit to open a relay when the charge
is complete as agaiin, you must use very expensive HVDC contactors and or
snubbers.  And by th time you do all that , you could have build a more
direct DC/DC converter.

So again, this is just an emergency data point.  For example, while drawing
1 kW (80 amps) from my prius 12v battery to power the house, all I need at
240v DC is 4 amps from the solar array.  And in my 14 year old Priuses I
know exactly where the HV battery posts are and can connect there and am
happy to take the risk.  Not sure I wouild take the risk for the 350v
battry in the newer Volt (which could give me 2 kW from its DC/DC
converter)..

Anyway. just thought I would mention it.  Oh, and the open circuit voltage
of the solar arrays on the brightest and coldest day can approach 600
volts, not the 450 nominal load point...  But again, just short that 600
volts with an ampmeter and you will still see only the 7, 8 or 9 amp
current from your arry even at zero volts.  Just protect your eyes from the
arc flash when you disconnect (oh, it will also vaporize pieces off your
clip leads too each time), and it can just melt the tip off the copper wire
to molten copper and catch fire to the insulation and anything else within
a few inches if you let the arc continue...)..

NOT SOMETHING TO PLAY AROUND WITH!

But you can charge any battery... ;-)

Bob


On Sun, Sep 1, 2019 at 2:17 PM Robert Bruninga  wrote:


 Again, if you find a 72v UPS (6 12v batteries) then you can tap your
 arrays in groups of three and use that to provide the current to the UPS to
 dirive your car charger.  Just 9 panels in 3 parallel strings of 90v will
 give maybe 20 amps (or the minimum needed to charge L1)  But 12 panels (or
 about one string array) will give you plenty of current over more hours of
 the day.  That's why I like string inverters beccause I have access to all
 the DC inputs and ground mount so I can get to them any time I want.

 Bob

 On Sun, Sep 1, 2019 at 1:20 PM Robert Bruninga  wrote:


 You already have what you need for continuous operation at night in the 1
 kW class (refrigerator, well pump and lights, etc)
 See http://aprs.org/powerwheels.html

 But it assumes you have the Sunny Boy GT inverter with "secure" power
 when the grid goes down to charge your EV.  $1500
 Or if you are lucky to find a UPS of at least 1800W capacity to charge
 the car, and then you can drive that from batteries that you charge from
 voltage taps on y our DC array that match the input voltage of the UPS.
 But ONLY if you seriouisly know what you are doing and do not overcharge
 the intermediate battery., etc.

 Bob

 On Sun, Sep 1, 2019 at 12:28 PM Damon Henry via EV 
 wrote:


 I know there has been a lot of churn the last few  years over Vehicle to
 Grid technology.  I'm not sure h

Re: [EVDL] V2G for my grid tied solar? (constant current charging)

[Robert Bruninga via EV]

One final point about grid down charging (under a must have armagedon
scenario): (And only for those fully experienced in HVDC)

 Remember that Solar panels are current limited power sources.  This means
It will provide its rated current at ANY voltage from 0 (short circuit) up
to its nominal operating voltage.

This means I can just clip the 450 volts DC straight from any one of my 3
kW solar panel arrays and run it straight to a 12, 24, 48, or 72 volt
battery (or 240v prius) directly for a temoporary 7 to 9 amp charge. WHICH
ONE MUST MONITOR to know when to disconnect.  AND one must have arc-flash
eye protection because you will draw a lightening bright arc flash when you
disconnect (and or while connecting if the connection is not made
cleanly).  But you will get a 7 amp charge (in my case of older panels).
New 300W panels can give 9 amps.

(You MUST disconnect from your GT inverter of course,.  You do not want any
capacitor holding the 450v or it is no longer a perfect current limited
source).

And with 6 such separate panel arrays, I can combine the currents at the
battery to give me up to 42 amps at 12, 24, 48, 72... (or 240) volts if
needed.  But again MUST human monitor in real time.  It is not easy to
throw together a charge regulating circuit to open a relay when the charge
is complete as agaiin, you must use very expensive HVDC contactors and or
snubbers.  And by th time you do all that , you could have build a more
direct DC/DC converter.

So again, this is just an emergency data point.  For example, while drawing
1 kW (80 amps) from my prius 12v battery to power the house, all I need at
240v DC is 4 amps from the solar array.  And in my 14 year old Priuses I
know exactly where the HV battery posts are and can connect there and am
happy to take the risk.  Not sure I wouild take the risk for the 350v
battry in the newer Volt (which could give me 2 kW from its DC/DC
converter)..

Anyway. just thought I would mention it.  Oh, and the open circuit voltage
of the solar arrays on the brightest and coldest day can approach 600
volts, not the 450 nominal load point...  But again, just short that 600
volts with an ampmeter and you will still see only the 7, 8 or 9 amp
current from your arry even at zero volts.  Just protect your eyes from the
arc flash when you disconnect (oh, it will also vaporize pieces off your
clip leads too each time), and it can just melt the tip off the copper wire
to molten copper and catch fire to the insulation and anything else within
a few inches if you let the arc continue...)..

NOT SOMETHING TO PLAY AROUND WITH!

But you can charge any battery... ;-)

Bob


On Sun, Sep 1, 2019 at 2:17 PM Robert Bruninga  wrote:

> Again, if you find a 72v UPS (6 12v batteries) then you can tap your
> arrays in groups of three and use that to provide the current to the UPS to
> dirive your car charger.  Just 9 panels in 3 parallel strings of 90v will
> give maybe 20 amps (or the minimum needed to charge L1)  But 12 panels (or
> about one string array) will give you plenty of current over more hours of
> the day.  That's why I like string inverters beccause I have access to all
> the DC inputs and ground mount so I can get to them any time I want.
>
> Bob
>
> On Sun, Sep 1, 2019 at 1:20 PM Robert Bruninga  wrote:
>
>> You already have what you need for continuous operation at night in the 1
>> kW class (refrigerator, well pump and lights, etc)
>> See http://aprs.org/powerwheels.html
>>
>> But it assumes you have the Sunny Boy GT inverter with "secure" power
>> when the grid goes down to charge your EV.  $1500
>> Or if you are lucky to find a UPS of at least 1800W capacity to charge
>> the car, and then you can drive that from batteries that you charge from
>> voltage taps on y our DC array that match the input voltage of the UPS.
>> But ONLY if you seriouisly know what you are doing and do not overcharge
>> the intermediate battery., etc.
>>
>> Bob
>>
>> On Sun, Sep 1, 2019 at 12:28 PM Damon Henry via EV 
>> wrote:
>>
>>> I know there has been a lot of churn the last few  years over Vehicle to
>>> Grid technology.  I'm not sure how many people really want the utilities to
>>> take over their vehicle state of charge, so I'm not sure how viable the
>>> whole concept is.
>>>
>>> With my grid tied solar system my solar stops producing if the grid goes
>>> down.  One way to prevent this is to have a battery backup system in
>>> place.  That's usually an investment of at least several thousand dollars.
>>>
>>> I have two factory OEM PHEVs sitting in my driveway with significant
>>> battery packs.  I also have a Juicebox 40 for charging which has some
>>> charging intelligence already built into it for their Juicenet program, but
>>> not really V2G.  I feel like I am tantalizingly close to a great solution.
>>>
>>> So here is the question that I have.  How far am I from being able to
>>> utilize my car batteries through the OEM port and an EVSE charger, to feed
>>> an inverter and keep my house 

Re: [EVDL] V2G for my grid tied solar?

[Robert Bruninga via EV]

Again, if you find a 72v UPS (6 12v batteries) then you can tap your
arrays in groups of three and use that to provide the current to the UPS to
dirive your car charger.  Just 9 panels in 3 parallel strings of 90v will
give maybe 20 amps (or the minimum needed to charge L1)  But 12 panels (or
about one string array) will give you plenty of current over more hours of
the day.  That's why I like string inverters beccause I have access to all
the DC inputs and ground mount so I can get to them any time I want.

Bob

On Sun, Sep 1, 2019 at 1:20 PM Robert Bruninga  wrote:

> You already have what you need for continuous operation at night in the 1
> kW class (refrigerator, well pump and lights, etc)
> See http://aprs.org/powerwheels.html
>
> But it assumes you have the Sunny Boy GT inverter with "secure" power when
> the grid goes down to charge your EV.  $1500
> Or if you are lucky to find a UPS of at least 1800W capacity to charge the
> car, and then you can drive that from batteries that you charge from
> voltage taps on y our DC array that match the input voltage of the UPS.
> But ONLY if you seriouisly know what you are doing and do not overcharge
> the intermediate battery., etc.
>
> Bob
>
> On Sun, Sep 1, 2019 at 12:28 PM Damon Henry via EV 
> wrote:
>
>> I know there has been a lot of churn the last few  years over Vehicle to
>> Grid technology.  I'm not sure how many people really want the utilities to
>> take over their vehicle state of charge, so I'm not sure how viable the
>> whole concept is.
>>
>> With my grid tied solar system my solar stops producing if the grid goes
>> down.  One way to prevent this is to have a battery backup system in
>> place.  That's usually an investment of at least several thousand dollars.
>>
>> I have two factory OEM PHEVs sitting in my driveway with significant
>> battery packs.  I also have a Juicebox 40 for charging which has some
>> charging intelligence already built into it for their Juicenet program, but
>> not really V2G.  I feel like I am tantalizingly close to a great solution.
>>
>> So here is the question that I have.  How far am I from being able to
>> utilize my car batteries through the OEM port and an EVSE charger, to feed
>> an inverter and keep my house alive and my solar producing during a power
>> outage?  Is this tech currently being developed, or is it still just a
>> dream that my come true some day?
>>
>> BTW - I have lived in my house for 20+ years and rarely lose power, but
>> "being prepared" is always on my agenda.  I suspect that if I really want a
>> solution within the next couple of years I will need to buy a separate
>> battery for my solar system, or a generator...
>>
>> thanks
>> Damon
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>> http://groups.yahoo.com/group/NEDRA)
>>
>>
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Re: [EVDL] V2G for my grid tied solar?

[Larry Gales via EV]

This is probably overkill for your particular needs, as it is based on
Tesla Model 3 cars, but here is the URL of a recent talk I gave on V2G:

https://staff.washington.edu/larryg/Energy/SEVA-V2G.pptx

On Sun, Sep 1, 2019 at 9:28 AM Damon Henry via EV  wrote:

> I know there has been a lot of churn the last few  years over Vehicle to
> Grid technology.  I'm not sure how many people really want the utilities to
> take over their vehicle state of charge, so I'm not sure how viable the
> whole concept is.
>
> With my grid tied solar system my solar stops producing if the grid goes
> down.  One way to prevent this is to have a battery backup system in
> place.  That's usually an investment of at least several thousand dollars.
>
> I have two factory OEM PHEVs sitting in my driveway with significant
> battery packs.  I also have a Juicebox 40 for charging which has some
> charging intelligence already built into it for their Juicenet program, but
> not really V2G.  I feel like I am tantalizingly close to a great solution.
>
> So here is the question that I have.  How far am I from being able to
> utilize my car batteries through the OEM port and an EVSE charger, to feed
> an inverter and keep my house alive and my solar producing during a power
> outage?  Is this tech currently being developed, or is it still just a
> dream that my come true some day?
>
> BTW - I have lived in my house for 20+ years and rarely lose power, but
> "being prepared" is always on my agenda.  I suspect that if I really want a
> solution within the next couple of years I will need to buy a separate
> battery for my solar system, or a generator...
>
> thanks
> Damon
> -- next part --
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>
>

-- 
Larry Gales
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Re: [EVDL] V2G for my grid tied solar?

[Willie via EV]

On 9/1/19 1:10 PM, Willie wrote:

Here is some discussion of augmenting a microgrid (or real grid) with EV 
12v:


I don't know where that come from


https://teslamotorsclub.com/tmc/threads/audio-album-artwork-not-appearing.12635/ 


Maybe this will be the right one:
https://teslamotorsclub.com/tmc/threads/powerwall-2-0-backup-runtime-extender.126358/


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Re: [EVDL] V2G for my grid tied solar?

[Willie via EV]

On 9/1/19 11:28 AM, Damon Henry via EV wrote:

I know there has been a lot of churn the last few  years over Vehicle to Grid 
technology.  I'm not sure how many people really want the utilities to take 
over their vehicle state of charge, so I'm not sure how viable the whole 
concept is.

With my grid tied solar system my solar stops producing if the grid goes down.  
One way to prevent this is to have a battery backup system in place.  That's 
usually an investment of at least several thousand dollars.

I have two factory OEM PHEVs sitting in my driveway with significant battery 
packs.  I also have a Juicebox 40 for charging which has some charging 
intelligence already built into it for their Juicenet program, but not really 
V2G.  I feel like I am tantalizingly close to a great solution.


AFAIK, all car J1772  ports are inherently one way; they feed ac current 
to the onboard charger.  One exception is Tesla where a single charge 
port either accesses the battery (at SuperChargers) or behaves exactly 
like a J1772 port.  So, for home power from an EV, the chademo/combo 
port is a better candidate.  The biggest problem seems to be that EV 
makers do not wish that to happen.


This V2H problem is something I've been considering seriously for 
several months.  I have three electric meters and I got a PowerWall 
installed on one last year.  I am extremely happy with the PW but much 
less so with "Tesla Energy", the Tesla branch that deals with municipal 
and residential battery backups as well as PV.  It seems Tesla does not 
wish to sell many PWs.  Anyway, I've been looking at other microgrid 
alternatives and have not found anything compelling.  Jack Rickard 
(EVTV) is offering some interesting stuff, though.


I would like to have a cheap very minimal microgrid which functions like 
a PW.  With the recent discussion of pulling up to 1kw out of any EV 
through the 12v DC-DC, I've become interested in trying to use an EV's 
12v to add up to a kw to my imagined minimal microgrid.  I've been 
experimenting trying to power an Enphase M215 from an EV 12v.  I'm 
stepping up the voltage to 20-30 but have not had sucess.  I do not 
understand MPPT and think that is the likely source of my trouble.


A minimal microgrid would be limited in power but could supply more than 
a PW's worth of energy over night.


So here is the question that I have.  How far am I from being able to utilize 
my car batteries through the OEM port and an EVSE charger, to feed an inverter 
and keep my house alive and my solar producing during a power outage?  Is this 
tech currently being developed, or is it still just a dream that my come true 
some day?


Word is, that Tesla has the grid or gridtie inverter already built into 
the power electronics.  We hope that that V2H capability will some day 
magically appear via a software update.  I see it possible that a Tesla 
could back feed through a Tesla "Wall Connector".  Wall Connectors can 
do up to 20kw so it should be possible to supply a house via that route.


BTW - I have lived in my house for 20+ years and rarely lose power, but "being 
prepared" is always on my agenda.  I suspect that if I really want a solution within 
the next couple of years I will need to buy a separate battery for my solar system, or a 
generator...


My situation is that I have up to 100wkh per day from PV but need only 
about 20kwh.  So, I am selling most of my PV energy to my utility. 
During the day, I am awash in power.  When/if the grid goes down, most 
of that power will go to waste.


I will hijack your thread and ask if anyone has microgrid suggestions or 
can give some guidance on using a gridtie inverter on not PV power.


I'm very pleased you brought the topic up.

Here is some discussion of augmenting a microgrid (or real grid) with EV 
12v:


https://teslamotorsclub.com/tmc/threads/audio-album-artwork-not-appearing.12635/
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Re: [EVDL] V2G for my grid tied solar?

[Robert Bruninga via EV]

You already have what you need for continuous operation at night in the 1
kW class (refrigerator, well pump and lights, etc)
See http://aprs.org/powerwheels.html

But it assumes you have the Sunny Boy GT inverter with "secure" power when
the grid goes down to charge your EV.  $1500
Or if you are lucky to find a UPS of at least 1800W capacity to charge the
car, and then you can drive that from batteries that you charge from
voltage taps on y our DC array that match the input voltage of the UPS.
But ONLY if you seriouisly know what you are doing and do not overcharge
the intermediate battery., etc.

Bob

On Sun, Sep 1, 2019 at 12:28 PM Damon Henry via EV 
wrote:

> I know there has been a lot of churn the last few  years over Vehicle to
> Grid technology.  I'm not sure how many people really want the utilities to
> take over their vehicle state of charge, so I'm not sure how viable the
> whole concept is.
>
> With my grid tied solar system my solar stops producing if the grid goes
> down.  One way to prevent this is to have a battery backup system in
> place.  That's usually an investment of at least several thousand dollars.
>
> I have two factory OEM PHEVs sitting in my driveway with significant
> battery packs.  I also have a Juicebox 40 for charging which has some
> charging intelligence already built into it for their Juicenet program, but
> not really V2G.  I feel like I am tantalizingly close to a great solution.
>
> So here is the question that I have.  How far am I from being able to
> utilize my car batteries through the OEM port and an EVSE charger, to feed
> an inverter and keep my house alive and my solar producing during a power
> outage?  Is this tech currently being developed, or is it still just a
> dream that my come true some day?
>
> BTW - I have lived in my house for 20+ years and rarely lose power, but
> "being prepared" is always on my agenda.  I suspect that if I really want a
> solution within the next couple of years I will need to buy a separate
> battery for my solar system, or a generator...
>
> thanks
> Damon
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[EVDL] V2G for my grid tied solar?

[Damon Henry via EV]

I know there has been a lot of churn the last few  years over Vehicle to Grid 
technology.  I'm not sure how many people really want the utilities to take 
over their vehicle state of charge, so I'm not sure how viable the whole 
concept is.

With my grid tied solar system my solar stops producing if the grid goes down.  
One way to prevent this is to have a battery backup system in place.  That's 
usually an investment of at least several thousand dollars.

I have two factory OEM PHEVs sitting in my driveway with significant battery 
packs.  I also have a Juicebox 40 for charging which has some charging 
intelligence already built into it for their Juicenet program, but not really 
V2G.  I feel like I am tantalizingly close to a great solution.

So here is the question that I have.  How far am I from being able to utilize 
my car batteries through the OEM port and an EVSE charger, to feed an inverter 
and keep my house alive and my solar producing during a power outage?  Is this 
tech currently being developed, or is it still just a dream that my come true 
some day?

BTW - I have lived in my house for 20+ years and rarely lose power, but "being 
prepared" is always on my agenda.  I suspect that if I really want a solution 
within the next couple of years I will need to buy a separate battery for my 
solar system, or a generator...

thanks
Damon
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