# why direct current(DC) can be stored but alternating current(AC) can not be?

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Why direct current (DC) can be stored but alternating current(AC) can not be?

Current means flow of charge per unit second.

Any flow cannot be made stationary. Then it is not flow.

Hence both direct current and alternating current cannot be stored.

We can store only charges.

In capacitors we store charges and not current.

For storing we use direct supply or direct voltage

When a capacitor is connected to a battery, which is a source of direct voltage, each plate of the condenser get charged. Charges remain in the plates. No current flows in between the plates.

When the source is removed, there are some charges left in the plates.

We say that charges are stored in the plates.

If an alternating source of supply is connected in between the plates,every instant ,the charges in the plates are alternating and they are not stationary.

When ac supply is removed, all the charges move out of the plates and hence no charge is left in them.

Hence charges can be stored with dc supply and not with ac supply.

However as long as the ac is connected to the capacitor, the capacitor gets stored and emptied with the frequency of the ac supply.

You cannot store ac as the reason why we are able to "store" is because of the difference in charges between the two terminals.Now for ac this is not possible as the current flows in either direction so there can never be a time long enough for storage for later use.

• goring
Lv 6

Storage of electrical charge(electron energy) is accomplished by usage of a Capacitor. The Capacitor charges up to a certain voltage exponentially.

The capacitor remains charged until the circuit is switched.At that point it returns the charge to the circuit.

In AC current the circuit is switched 60 time per second.Therefore the capacitor charges and discharges depending on the Frequency of the AC current.

In DC circuit the capacitor charges than holds the charge unless the circuit is interrupted(switched)

• 3 years ago

Can We Store Ac Power

You can 'store' AC. In a resonant circuit of an inductor and a capacitor, the energy continually moves between the magnetic field of the inductor to the electric field of the capacitor. It's not practical for energy storage because the losses are so high.

• Anonymous

Very simply, a battery has an area of high electron potential and an area of low potential. It is the movement of those electrons (from high to low) that we call an electric current. The potential charge is static requiring a wire etc to complete the 'circuit'. For a batttery to produce an AC current the electrons would have to move inside the battery from end to end which is not very practical.

• Mike
Lv 4

DC is "stored" by a device with two areas - one with an abundance of electrons and the other with a deficit of electrons. Nature wants a balance, so you can utilize the imbalance and cause a flow of electrons (current) from one section to the other.

In order to store AC you would need two areas that fluctuate from having too many electrons to not having enough electrons in sync with one another, but opposite.

.... hmmm... that's kind of confusing. Maybe someone else...