We sent bitcoin from Miami to a Ukrainian in Poland who withdrew it as cash, all in less than three minutes

Before Russia invaded Ukraine in February, Alena had not thought about the digital currency. Cash shortages at ATMs across the country, border closings and shelling, and the central bank suspending electronic cash transfers all led to her giving up on paper money.

When you send $100 from the U.S. to Ukraine, the cost of the transaction is slashed to zero by using the Lightning Network.

The war rages on in western part of Ukraine, so CNBC decided to put the test of lightning payments to the test with the expertise and translation skills of Gleb Naumenko, who is currently hiding out in that area.

The bottom line? It does work, as well as the boosters say it does.

It took less than an hour to download a wallet onto a phone, transfer money from the U.S. to Poland, and withdraw the equivalent in Polish currency from a ATM.

Alena Vorobiova withdraws Polish zloty from a bitcoin ATM in Poland.

On a road trip from Houston to Dallas last August, Peter McCormack, founder and host of the popular What Bitcoin Did, taught CNBC how to use the Lightning Network to make instant payments to anyone in the world.

We downloaded the Blue wallet app and created a one-time invoice in the form of a QR code, which took less than 60 seconds to do. He scanned the code on his phone and transferred 100,000 sats from his account to ours. The transfer was worth about $50.

CNBC decided to pay that knowledge and some of those sats after eight months, from a hotel room in Miami on the sidelines of the Bitcoins conference.

We followed a similar sequence of events on a three-way video call with CNBC in Miami.

The Muun wallet app was downloaded and used to make a four-digit pin and generate an invoice. Over 50,000 sats were transferred from McCormack to CNBC using the Scan mode in the Blue wallet. The fees were fractions of a penny. For the experiment, Naumenko transferred another 50,000 because the ATM had a minimum withdrawal amount.

According to Jeff Czyz, the Basis of Lightning Technology specification, which defines a layer-2 protocol for sending payments across the Lightning Network, is compatible with Lightning wallets.

Czyz, a developer with Jack Dorsey's team known as Spiral, said that sending money between banks requires them to speak the same language. The specification is a common language.

The Lightning Network consists of payment channels which are used to forward payments across the network without the need for trust.

Alena Vorobiova withdraws Polish zloty from a bitcoin ATM in Poland.

The process of transferring sats from Miami to Wroc is similar to the one in the car.

After following her sister and niece to the Polish city of Wrocław, she went to one of the fifteen bitcoin ATMs and requested a withdrawal.

She was able to do this by using the ATM. She used the Muun app on her phone and scanned the QR code into it, which led to the transfer of her money to the ATM account. She ended up with 170 zloty, the Polish currency, worth about 100,000 sats. The ATM company took a fee for every transaction.

Czyz explained that it was the same as making a payment for a good or service using Lightning.

This was a fun experiment for Vorobiova. She tells CNBC that she is following the instructions of the Ukrainian regulators and using credit cards for the time being.

The process shows how refugees with no cash or a way to access their belongings can use a digital wallet.

Some Ukrainians use it to facilitate peer-to-peer transactions, while others use it to receive donations from anywhere in the world. In Poland there are more than 175 ATMs that allow refugees to cash in their fleeing with the digital currency.

Gladstein said he could send you money instantly to your phone.

We don't have to worry about that. It doesn't matter if you don't have a bank account or a Polish passport. Gladstein said that none of these things mattered.