Why not use capacitors to store power instead of batteries ?

[DirtyRob]

Just dont get too slap happy. Hate for you to knock a guy like this Robert Murray-Smith and his 1MF capacitor down. I can see even when these are feasible in the home that you guys are going to be a tough sell. Thats ok. I still have to walk my grandma through how to retrive her email from time to time because of how her generation took to computers. Its part of life.

[solarix]

Right on.....

[Mike90250]

forums all over the internet do indeed have their own feel. This one is pretty much rooted in reality, and in being legal. Sure you can buy gear made by some no-name company overseas, plug it in, and the electric bill goes down. Then one day you have a grease fire in the kitchen, and the fire department, in the clean up, hauls out some smokey plug in inverter, your insurance adjuster sees that and voids your policy. We don't want that to happen, it gives genuine solar power a bad name.
We want to do it safe, not see you in the poor house afterwards. Going off grid - sure, as long as you really understand what the cost is going to be.
But we do blast the dreams of some who arrive with all sorts of unrealistic hopes, we don't feed the hopes, we will say what will and won't work, and will offer work-a-rounds, suggestions for improvements. But woe to the vendor coming here to peddle clean blue energy bars that will run your fridge *(for 10 minutes) and smell like fresh mown lawn. We'll slap them back to PT Barnum 101. We want folks to have a good solar/off grid experience, and for them to know that it's really a 9-15 year payback, regardless what the salesman says. Informed customers are good customers.
And the sales pitch is uh, support the sponsor of the board if you can, Not a lot of ads, moderators are volunteers, we don't make a penny here, and it eats into my 12Gb monthly data allowance. (off grid, internet via cell phone hotspot).
Mike

[inetdog]

Well, I invite you to run your home from that. But I did error in presenting/formulating my question, While the giant phase shift cap banks can perhaps contain enough energy to power a house, the problem is that it's not "useful" energy. Has to be converted to AC to be utilized in the house, and at the right voltage.

Actually, the problem is more that although it might deliver enough power for a house, it could only power that house for a few seconds and would then need to be charged up again.
Power Factor Correction capacitors (PFCs) are designed to store and release energy over the time range of 1/240 of a second. Not much use when the AC goes away.

Remember that energy is related to power over time. You can have all the power you want for a very short time and you will still not have much energy.
But when you have a load that consumes power at an average rate of 1kW, you need to supply 24kWh per day to keep it running. That is lot of energy to store.

Your super capacitor can deliver as much current as a AA battery for a short time, but I really doubt that it can deliver the same number of milliamp hours (the common measure of battery capacity), nor the same number of watt-hours (the precise measure of the available energy over one cycle.)

[DirtyRob]

You have to understand that for some of us we have read quite a few posts from people that come here with very outlandish ideas on how easy it would be to use xyz to generate power without even understanding the physics or difficulties behind what it would take to do that especially on a "grid size" scale.

So we push back hard when maybe we should just roll our eyes and say "yeah well maybe that might work some day"

Anyway, I guess I could start talking about "singularities" or "anti-matter" being used to generate power but I don't think I could handle the hate mail.

I getcha I getcha, but what are forums for? What do you guys only talk about selling commercial units to consumers on here? This isn't some tech support forum for an actual solar panel company is it?

Admittedly this is the first thread I saw in this forum and it caught my eye and is why I joined. I didn't really get a feel for the community before posting, so that's on me.

[Mike90250]

every town over 10000 people has capacitor banks for AC transmission that are of a class to run a single house no problem.

Well, I invite you to run your home from that. But I did error in presenting/formulating my question, While the giant phase shift cap banks can perhaps contain enough energy to power a house, the problem is that it's not "useful" energy. Has to be converted to AC to be utilized in the house, and at the right voltage.

[SunEagle]

Over the horizon I can live with. The response ive been getting here is downright fanatical to a fault.

You have to understand that for some of us we have read quite a few posts from people that come here with very outlandish ideas on how easy it would be to use xyz to generate power without even understanding the physics or difficulties behind what it would take to do that especially on a "grid size" scale.

So we push back hard when maybe we should just roll our eyes and say "yeah well maybe that might work some day"

Anyway, I guess I could start talking about "singularities" or "anti-matter" being used to generate power but I don't think I could handle the hate mail.

[DirtyRob]

But they won't run your lights or appliances for very long.

Look caps have their place (I know, I spec them in power quality filters, as well as have to deal with them causing 11th harmonic distortion) but as an energy storage system, that technology is still a little over the horizon.

Over the horizon I can live with. The response ive been getting here is downright fanatical to a fault.

[DirtyRob]

Please please tells us how is this possible and what does the capacitor do? PLEASE PLEASE TELL US.

Pretty Please With Sugar On Top tell us more about HYDROGEN.

We all need a good laugh today.

Just saying its not a "waste of energy" to burn energy in the repackaging of fuels for people to consume later down the road. You can laugh at that all you want.

I'm sure the biggest laugh ill get is going to work and telling the guys we should rip up all our contracts because the 'Sunking' and 'Mike90250' at solarpaneltalk.com say their pie hole is more valid and electric theory isn't sound enough to be making things using these principles. We must have been out of our minds. What were we thinking? We should probably just shut down the fab.

[SunEagle]

They have those same power sub stations configured to smooth out brownouts over 10s of thousands of houses, and they do it without batteries.

But they won't run your lights or appliances for very long.

Look caps have their place (I know, I spec them in power quality filters, as well as have to deal with them causing 11th harmonic distortion) but as an energy storage system, that technology is still a little over the horizon.

[DirtyRob]

He might be talking about power factor capacitor banks the POCO uses to keep the feeder voltage within limits. Those banks are usually in the 1500kvar range but still won't store much energy so I am still not sure what DirtyRob is talking about.

They have those same power sub stations configured to smooth out brownouts over 10s of thousands of houses, and they do it without batteries. You could also incorporate high efficiency vacuum fly wheels to hold energy. You can feed those very efficiently with capacitors despite any quick discharging that occurs. and because youd be feeding them inductively youd keep your house separate from the caps direct discharge themselves ... if that's what youre afraid of.

[DirtyRob]

Yeah the voltage adds, but not the capacity, it divides. The more you add in series, the less you have.

SuperCaps is what you are talking about and SuperCaps are good at doing one thing and one thing only. Storing and Releasing energy real darn fast measured in a second or less. Batteries cannot do that. Great for things like electronic energy weapons, strobes, flashes, or reen braking. In theory sure you could use Capacitors to store energy, but in practice will not work. They horrible self-discharge rates, specific energy (wh/Kg), energy density wh/L, and cost wh/$.

Who wants a battery that weighs 10 times more, occupies 8 times more space, and cost 20 times more than Pb for a given amount of energy. Only thing special it will do is be charged in 1 second if you had a source that could possible do that.

Thats funny that you say that because I'm looking at one across the table here from me that's half the size of a AA battery, a fraction of the weight (even with my pcb attached), and performs the exact same function ... better if you consider I can charge it in an instant and don't have to pitch it when it drops a couple tenths of a volt.

Check out some car battery replacements if you want to see a size difference. And those are using a source that's only charging when the engines running ... and its done charged a second after it turns over.

[SunEagle]

Please please tells us how is this possible and what does the capacitor do? PLEASE PLEASE TELL US.

Pretty Please With Sugar On Top tell us more about HYDROGEN.

We all need a good laugh today.

He might be talking about power factor capacitor banks the POCO uses to keep the feeder voltage within limits. Those banks are usually in the 1500kvar range but still won't store much energy so I am still not sure what DirtyRob is talking about.

[Sunking]

Well for starters, commercially speaking, every town over 10000 people has capacitor banks for AC transmission that are of a class to run a single house no problem.

Please please tells us how is this possible and what does the capacitor do? PLEASE PLEASE TELL US.

Pretty Please With Sugar On Top tell us more about HYDROGEN.

We all need a good laugh today.

[Sunking]

It doesnt take a moron, but a masters, to think capacitors dont add voltage in series, .

Yeah the voltage adds, but not the capacity, it divides. The more you add in series, the less you have.

SuperCaps is what you are talking about and SuperCaps are good at doing one thing and one thing only. Storing and Releasing energy real darn fast measured in a second or less. Batteries cannot do that. Great for things like electronic energy weapons, strobes, flashes, or reen braking. In theory sure you could use Capacitors to store energy, but in practice will not work. They horrible self-discharge rates, specific energy (wh/Kg), energy density wh/L, and cost wh/$.

Who wants a battery that weighs 10 times more, occupies 8 times more space, and cost 20 times more than Pb for a given amount of energy. Only thing special it will do is be charged in 1 second if you had a source that could possible do that.