Hi @tropic"whilst sun is shining" Is a valid concern but there...

Hi @tropic

"whilst sun is shining" Is a valid concern but there are solutions rapidly emerging.
There are many very large VRFB's (Vanadium Redox Flow Battery projects), World wide.
Below is some information that you may be aware of. I only chose one website. I have no vested interest in the company I have referenced.
The reference is an Australian company and there are others in the same space that I am aware of.

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The vanadium redox flow battery (VRFB) is considered to be a milestone in the history of regenerative energy management, well suited to many sustainable energy applications. Whether in combination with solar PV (photovoltaic), wind power, biogas generators or in parallel operation – the VRFB ensures uninterrupted power supply.

The vanadium redox flow battery is independent of weather and temperature fluctuations, length of day and unstable grids.

The range of VRFBs we offer have a reference showing the number of kilowatts of power output and the number of kilowatt hours of storage.
A 10/40, for example, is a flow battery with 10kW of power and 40kWh of storage with the ability to provide the 10kW for 4 hours; a 250/2000 is a flow battery with 250kW of power output and 2000kWh (2MWh) of storage with the ability to deliver 250kW of power for 8 hours (Remember this is still scalable further)

POWER STABILITY
The VRFB can stabilise grid supply through frequency control, smoothing and demand response.

BACKUP
Never worry about power outages again – VRFB energy storage guarantees uninterrupted power supply.

SCALABILITY
The VRFB is modular, so your solution will be tailor-made to meet your energy requirements, be it kilowatts or megawatts.

• An energy battery, able to store large amounts of energy for later use
• Easy to scale by adding modules or introducing larger electrolyte tanks
• Lifespan of over 20 years with no degradation in performance over time
• Non-flammable, making it safer than other batteries on the market
• Can charge and discharge at the same time 100% depth of discharge with no lifetime capacity loss
• The vanadium electrolyte can be reused indefinitely

Reference Link Click Here

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A VRFB (Vanadium Redox Flow Battery) project in Malaysia
JUNE 22, 2021
Malaysian VRFB project Reference Click here

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Worlds Largest Vanadium Redox Flow Battery is in China
SEPTEMBER 29, 2022
China connects world’s largest redox flow battery system to grid
Dalian Rongke Power has connected a 100 MW redox flow battery storage system to the grid in Dalian, China.
It will start operating in mid-October and will eventually be scaled up to 200 MW.
The vanadium redox flow battery technology was developed by a division of the Chinese Academy of Sciences.
Worlds Largest VRFB Article Reference Click Here

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Here is a good article relating to the rapid rise of Vanadium Flow Batteries
Growth of CAGR of 32.3% by 2026
Flow Battery Market Rising Trends 2022 Reference Click Here

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Regards

Ken