DC Battery storage into Tesla Powerwall

NikoV6
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DC Battery storage into Tesla Powerwall

#1

Post by NikoV6 »

Clearly, being an AC system PowerWall will not take DC directly.

However, as the DC generation from my solar array could be stored in a DC battery, then converted to AC by hybrid inverter. Surely its just a case of adding that inverter output to Tesla gateway in the same manner as the output of the current solar inverter.

Or is that noob talk? :lol:

Not an electrical specialist, I'm a mechanical engineer!
14Kw Mitsubishi Ecodan ASHP
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Fintray
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Re: DC Battery storage into Tesla Powerwall

#2

Post by Fintray »

NikoV6 wrote: Tue Feb 07, 2023 1:09 pm Clearly, being an AC system PowerWall will not take DC directly.

However, as the DC generation from my solar array could be stored in a DC battery, then converted to AC by hybrid inverter. Surely its just a case of adding that inverter output to Tesla gateway in the same manner as the output of the current solar inverter.

Or is that noob talk? :lol:

Not an electrical specialist, I'm a mechanical engineer!
That would be my method of doing it.
3.87kWp PV
10.24kWp PV SolarEdge system
Tesla Powerwall 2
100 x 47mm Navitron tubes (still being installed!) Now likely to be removed for more PV.
MK2 PV router DHW diverter
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Moxi
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Re: DC Battery storage into Tesla Powerwall

#3

Post by Moxi »

Mech Engineers rule!

:D

Moxi
NikoV6
Posts: 218
Joined: Thu Aug 11, 2022 6:42 am

Re: DC Battery storage into Tesla Powerwall

#4

Post by NikoV6 »

Fintray wrote: Tue Feb 07, 2023 1:19 pm
NikoV6 wrote: Tue Feb 07, 2023 1:09 pm Clearly, being an AC system PowerWall will not take DC directly.

However, as the DC generation from my solar array could be stored in a DC battery, then converted to AC by hybrid inverter. Surely its just a case of adding that inverter output to Tesla gateway in the same manner as the output of the current solar inverter.

Or is that noob talk? :lol:

Not an electrical specialist, I'm a mechanical engineer!
That would be my method of doing it.
PylonTech US5000 4.8kWh for £1650ish looks good value unless your research has found better?
14Kw Mitsubishi Ecodan ASHP
22 x JA Solar 455W Mono Perc Half Cell Silvers
Solis 8.0Kw 5G Dual MPPT Inverter
13.5Kw Tesla Powerwall
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NikoV6
Posts: 218
Joined: Thu Aug 11, 2022 6:42 am

Re: DC Battery storage into Tesla Powerwall

#5

Post by NikoV6 »

Moxi wrote: Tue Feb 07, 2023 1:24 pm Mech Engineers rule!

:D

Moxi
When I was in the RAF, we used to joke where's the leccy - normally sitting on the nearest radiator! :lol: :D
14Kw Mitsubishi Ecodan ASHP
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Fintray
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Re: DC Battery storage into Tesla Powerwall

#6

Post by Fintray »

NikoV6 wrote: Tue Feb 07, 2023 1:26 pm
Fintray wrote: Tue Feb 07, 2023 1:19 pm
NikoV6 wrote: Tue Feb 07, 2023 1:09 pm Clearly, being an AC system PowerWall will not take DC directly.

However, as the DC generation from my solar array could be stored in a DC battery, then converted to AC by hybrid inverter. Surely its just a case of adding that inverter output to Tesla gateway in the same manner as the output of the current solar inverter.

Or is that noob talk? :lol:

Not an electrical specialist, I'm a mechanical engineer!
That would be my method of doing it.
PylonTech US5000 4.8kWh for £1650ish looks good value unless your research has found better?
I was thinking more along the lines of the 280A batteries in a series string of 16 and into a hybrid inverter.
For around £10K you should be able to get about a 54kWh battery storage and 2 x 5kW hybrid inverters.
Last edited by Fintray on Tue Feb 07, 2023 1:37 pm, edited 1 time in total.
3.87kWp PV
10.24kWp PV SolarEdge system
Tesla Powerwall 2
100 x 47mm Navitron tubes (still being installed!) Now likely to be removed for more PV.
MK2 PV router DHW diverter
Morso 5kW WBS
Vaillant AroTherm 10kW ASHP
Nissan Leaf
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nowty
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Re: DC Battery storage into Tesla Powerwall

#7

Post by nowty »

NikoV6 wrote: Tue Feb 07, 2023 1:28 pm
Moxi wrote: Tue Feb 07, 2023 1:24 pm Mech Engineers rule!

:D

Moxi
When I was in the RAF, we used to joke where's the leccy - normally sitting on the nearest radiator! :lol: :D
When I was doing my apprenticeship we used to have a joke about what the favourite song of a Fitter was.
Although we had some modified lyrics to the original. :lol:

18.7kW PV > 109MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 27MWh generated
6 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 510 m3
NikoV6
Posts: 218
Joined: Thu Aug 11, 2022 6:42 am

Re: DC Battery storage into Tesla Powerwall

#8

Post by NikoV6 »

nowty wrote: Tue Feb 07, 2023 1:35 pm
NikoV6 wrote: Tue Feb 07, 2023 1:28 pm
Moxi wrote: Tue Feb 07, 2023 1:24 pm Mech Engineers rule!

:D

Moxi
When I was in the RAF, we used to joke where's the leccy - normally sitting on the nearest radiator! :lol: :D
When I was doing my apprenticeship we used to have a joke about what the favourite song of a Fitter was.
Although we had some modified lyrics to the original. :lol:

:lol: :lol:
14Kw Mitsubishi Ecodan ASHP
22 x JA Solar 455W Mono Perc Half Cell Silvers
Solis 8.0Kw 5G Dual MPPT Inverter
13.5Kw Tesla Powerwall
Zappi 2 Charger
iBoost
NikoV6
Posts: 218
Joined: Thu Aug 11, 2022 6:42 am

Re: DC Battery storage into Tesla Powerwall

#9

Post by NikoV6 »

Fintray wrote: Tue Feb 07, 2023 1:34 pm
NikoV6 wrote: Tue Feb 07, 2023 1:26 pm
Fintray wrote: Tue Feb 07, 2023 1:19 pm

That would be my method of doing it.
PylonTech US5000 4.8kWh for £1650ish looks good value unless your research has found better?
I was thinking more along the lines of the 280A batteries in a series string of 16 and into a hybrid inverter.
For around £10K you should be able to get about a 54kWh battery storage and 2 x 5kW hybrid inverters.
Hmm, could start off small and add to this then?

Can you link to where you could source please?
14Kw Mitsubishi Ecodan ASHP
22 x JA Solar 455W Mono Perc Half Cell Silvers
Solis 8.0Kw 5G Dual MPPT Inverter
13.5Kw Tesla Powerwall
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User avatar
nowty
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Joined: Mon May 31, 2021 2:36 pm
Location: South Coast

Re: DC Battery storage into Tesla Powerwall

#10

Post by nowty »

Fintray wrote: Tue Feb 07, 2023 1:19 pm
NikoV6 wrote: Tue Feb 07, 2023 1:09 pm Clearly, being an AC system PowerWall will not take DC directly.

However, as the DC generation from my solar array could be stored in a DC battery, then converted to AC by hybrid inverter. Surely its just a case of adding that inverter output to Tesla gateway in the same manner as the output of the current solar inverter.

Or is that noob talk? :lol:

Not an electrical specialist, I'm a mechanical engineer!
That would be my method of doing it.
Going back to the original theme. :geek:

The problem with the 2nd AC coupled battery / hybrid inverter is getting it to work harmoniously with the Powerwall and stop them competing with each other.
18.7kW PV > 109MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 27MWh generated
6 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 510 m3
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