# Power supply from super capacitor?

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#### dvdljns

Joined Jul 13, 2021
25
Despite the heading in the video, these are not what electronic engineers call super caps,
Super caps tend to have capacitances of Farads,
where as these have capacitance of u farad.
Ok a farad 1 million uf? So these are really 0.00005
Can you show a super capacitor then. And how does effect my design

#### dvdljns

Joined Jul 13, 2021
25
If that is your understanding, answer this question. Where does the "build up" in seconds come from? I don't think you understand at all. But then again, I'm not all that smart.
Or I don't understand. Just because that is what I found on the internet does not make it right. The build up is the charge. Solar panels, battery or generator. Build up is the way I think about in my mind.

#### MrChips

Joined Oct 2, 2009
27,641
The video shows these:

500F is a super capacitor.

You still cannot use these to replace 24kWh of electrical energy.
Do the math!

#### sagor

Joined Mar 10, 2019
786
The video shows these:

View attachment 243502

500F is a super capacitor.

You still cannot use these to replace 24kWh of electrical energy.
Do the math!
I showed the math (approximate) in post #5. The bank in the video will store about 2.27Wh at 14V. Even if he doubles that, he will get about 4.5Wh. The "power out" also assumes you get useful power as the voltage drops quickly under a heavy load, which most inverters or regulators won't do.
To get even close to 24kWh, he would need 10,000 banks of those capacitors (= 22.7kWh) as shown in the video.

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#### LesJones

Joined Jan 8, 2017
3,894
You seem to understand the formula for the amount of ENERGY (NOT POWER.) stored in a capacitor. C x V^2/2. The units are Farads, Volts and Joules. You keep talking about a POWER of 2KW (A rate of energy.) So this is 2000 Joules EVERY SECOND.
This is 2000 x 3600 = 7200000 Joules per hour.
You seem to be confused in the same way as if you did not understand the difference between distance and speed. Speed is distance traveled per unit of time. (For example miles per hour is distance in miles traveled every hour.)

Les.

#### dvdljns

Joined Jul 13, 2021
25
TS does not understand power generation vs power storage, and conservation of energy.
When you take into account losses, power generation must exceed power consumed. Hence it takes more energy to recharge the capacitors than the energy delivered by the capacitors.
Yes that much I know. when you transfer power you lose some. Takes 13.7 volts to charge a battery to 12 volts.

#### MrChips

Joined Oct 2, 2009
27,641
Yes that much I know. when you transfer power you lose some. Takes 13.7 volts to charge a battery to 12 volts.
Nice. But wrong. It takes 12V to charge a capacitor to 12V.
We are approaching the 50th post mark. What have you learned from this thread so far?

#### dvdljns

Joined Jul 13, 2021
25
You seem to understand the formula for the amount of ENERGY (NOT POWER.) stored in a capacitor. C x V^2/2. The units are Farads, Volts and Joules. You keep talking about a POWER of 2KW (A rate of energy.) So this is 2000 Joules EVERY SECOND.
This is 2000 x 3600 = 7200000 Joules per hour.
You seem to be confused in the same way as if you did not understand the difference between distance and speed. Speed is distance traveled per unit of time. (For example miles per hour is distance in miles traveled every hour.)

Les.
Power is total

#### MrChips

Joined Oct 2, 2009
27,641
We are going nowhere with this.
Time to shut this down.

#### dvdljns

Joined Jul 13, 2021
25
We are going nowhere with this.
Time to shut this down.
I agree. I need some other way to learn this circuit design. I don't doubt that I went at it the wrong way. I got us caught up in whether it would actually work instead of the physical build. Although I think I did state that the build was more important than getting it to work. Still as I stated I seem to have a hard time getting people to understand me. I hate to just buy the boarf and copy it. I don't think I will learn what I set out to learn that way but it seems the only way. Good bye and thank you for your time.

#### Ya’akov

Joined Jan 27, 2019
6,853
I agree. I need some other way to learn this circuit design. I don't doubt that I went at it the wrong way. I got us caught up in whether it would actually work instead of the physical build. Although I think I did state that the build was more important than getting it to work. Still as I stated I seem to have a hard time getting people to understand me. I hate to just buy the boarf and copy it. I don't think I will learn what I set out to learn that way but it seems the only way. Good bye and thank you for your time.
What will you do with it if you build it? What does "work" even mean in this case.

Seriously, if you build it how will you use it for anything? I can't imagine what you expect to happen.

#### dvdljns

Joined Jul 13, 2021
25
Nice. But wrong. It takes 12V to charge a capacitor to 12V.
One more thing before I go. A capacitor is not a battery. I don't care how many you put in series or how much electricity you put in them they are not batteries. They never will be batteries. Just like a battery is not and never will be a capacitor.

#### MrChips

Joined Oct 2, 2009
27,641
We have told you repeatedly why it will not work.
We have shown why it will not work by showing you the math.
We have given you guidance by doing the math for you which you for some reason refuse to do yourself.

#### MrChips

Joined Oct 2, 2009
27,641
One more thing before I go. A capacitor is not a battery. I don't care how many you put in series or how much electricity you put in them they are not batteries. They never will be batteries. Just like a battery is not and never will be a capacitor.
I have built a solar powered clock that uses no battery.
A solar panel charges a super capacitor which powers the clock at night and during the day when the sun does not shine through. Hence the capacitor takes the function of a rechargeable battery.

It works because I took the time and effort to calculate how much energy is required to run the clock for a week powered entirely from the charge stored in the super capacitor while still maintaining sufficient voltage to power the clock. This tells me how large the capacitor needs to be. Then I determine how much power I would need to recharge the capacitor from 4 hours of sunlight. This tells me the size the solar panel needs to be. It's all in the math.

#### LesJones

Joined Jan 8, 2017
3,894
It is not circuit design you are having problems with. It is the physics of electrical units. You can't start to design a circuit until you understand the basics of electricity. We were taught basic physics in school but its is over60 years since I left school so maybe now they don't teach any physics.

Les.

#### dvdljns

Joined Jul 13, 2021
25
What will you do with it if you build it? What does "work" even mean in this case.

Seriously, if you build it how will you use it for anything? I can't imagine what you expect to happen.
I expect to prove a capacitor is not a battery and have two system side by side to show exactly why. One system with super capacitors and one with batteries to show the differences between the two. And explain exactly why the people selling the boards and plans are cheating people. Working means completing the task given it like the battery can do. My rv has a system that runs everything from dc for 2 hours when not connecting to ac. It runs from a battery to a inverter for ac. If super capacitors could be a battery I could set up a system to do what my battery and inverter does if super capacitors could do that they could be batteries.

#### Papabravo

Joined Feb 24, 2006
19,551
I expect to prove a capacitor is not a battery and have two system side by side to show exactly why. One system with super capacitors and one with batteries to show the differences between the two. And explain exactly why the people selling the boards and plans are cheating people. Working means completing the task given it like the battery can do. My rv has a system that runs everything from dc for 2 hours when not connecting to ac. It runs from a battery to a inverter for ac. If super capacitors could be a battery I could set up a system to do what my battery and inverter does if super capacitors could do that they could be batteries.
It's a cliché, but if wishes were horses, beggars would ride.

#### dvdljns

Joined Jul 13, 2021
25
I that uses no battery.
Does it use no battery or is the super capacitor a battery?