Super capacitor storage

[mapsofilti]

I have been very impressed with super capacitors in my electrical engineering experience. I would like to explore the cost effectiveness of building a super capacitor bank for energy storage to use at night time, especially considering the costs of these components from overseas is decreasing as time goes on and perhaps a high quality super capacitor bank could outlast conventional solar battery systems by even a decade or more. For my plan in mind, it would need to have enough energy for roughly 50 kWh.

 

[DIYrich]

If it were cost effective, the utilities would have done it by now.

 

[toms]

Why would you use supercapacitor over LiFePO4? I use a hybrid system but it is for an edge case application requiring a small LiFePO4 battery and large inrush currents.

Other than that scenario i can’t see any advantages.

 

[Warpspeed]

I have been very impressed with super capacitors in my electrical engineering experience. I would like to explore the cost effectiveness of building a super capacitor bank for energy storage to use at night time, especially considering the costs of these components from overseas is decreasing as time goes on and perhaps a high quality super capacitor bank could outlast conventional solar battery systems by even a decade or more. For my plan in mind, it would need to have enough energy for roughly 50 kWh.

Just had a quick look on ebay, found this:
https://www.ebay.com.au/itm/395144813886?hash=item5c00775d3e:g:ES0AAOSwqxZi~xy7&amdata=enc:AQAIAAAAwONgRXSwgpFtK2EuKOSAuriQz4F1BjyE+os6anqTFivxhbh2e3dUL8czZt9YoydhjvUBOhiiURujg2ASpWavC3UcVppdAigHa0gO6ITZRNW2ZEVjiF40qO2TEdzcT48qd9kS2qfVFahVv6QZsy7KPvMdqlYWCttrUmRtsNnfiPMmbnmK3A/m7C4908GdIQjwlEl/VjtDQacWVHU8Ct45ELpBuC8/8McAU5nIskkIylfx5dhV1+XG5twxiuMjT284hg==|tkp:Bk9SR-aNvOquYw

166 Farads at 48v roughly $1,000 for a USED capacitor bank.

Charged up to 56v, stored energy = 1/2Cv squared.
166 divided by 2, multiplied by 56v x 56v = 260,288 Joules (watt seconds).
Discharged down to 40v, stored energy,
166 divided by 2, multiplied by 40v x 40v = 132,800 Joules.

Recoverable energy during discharge 260,288 - 132,800 = 127,488 Joules.
About half of the max initial stored energy, and you won't do much better than that.
127,488 watt seconds = 35.41 watt hours.

To get 50,000 watt hours we will need 50,000 divided by 35.41 = 1,449 of those thousand dollar batteries.

Do you have 1.5 million dollars to spend on a USED capacitor bank ?

 

[mapsofilti]

Do you have 1.5 million dollars to spend on a USED capacitor bank ?

OK, I think that arithmetic nips it in the bud. Thanks for that.

The only use case I can comprehend is perhaps a small bank to handle the brief surge demand of power through an inverter for things like motors or heaters starting up.

 

[v_green57]

OK, I think that arithmetic nips it in the bud. Thanks for that.

The only use case I can comprehend is perhaps a small bank to handle the brief surge demand of power through an inverter for things like motors or heaters starting up.

Which good LF inverter/chargers already have. Hence the big spark when I connect my Samlex to the battery bank by just touching the cabling to a battery post.

 

[Jbird2000]

I was just speaking with someone about this. From what he said they are about to launch a utility and a home based Super capacitor system. No details yet. I will update when he gets me the info

 

[Warpspeed]

OK, I think that arithmetic nips it in the bud. Thanks for that.

The only use case I can comprehend is perhaps a small bank to handle the brief surge demand of power through an inverter for things like motors or heaters starting up.

Yes, absolutely.
Capacitors are excellent for supplying and absorbing massive energy peaks for SHORT periods.
Batteries are a vastly more cost effective for supplying reasonably high energy over long periods.