Premium Bond number generator Ernie takes quantum leap

Computers, News


Ernie 5
Ernie 5, shown on the end of a pencil, is around the size of a grain of rice (NS&I/PA)

Premium Bond random number generator Ernie has taken a quantum leap as the fifth generation of the technology has been launched.

The new Ernie is a chip around the size of a grain of rice, whereas the original version was 3.5 metres long, weighed 1,500kg and was described as being the size of a van.

All previous Ernies have used thermal noise to produce random numbers – but Ernie 5 is powered by quantum technology, with the ability to produce random numbers through light.

This new technology, developed by ID Quantique (IDQ), has allowed Ernie to produce enough random numbers for March’s prize draw in just 12 minutes – more than 40 times faster than the nine hours that Ernie 4 took towards the end of its random number generating career.

After putting in 15 years of service, Ernie 4 has been decommissioned and replaced with a faster machine to cope with the increasing volume of numbers that have to be produced every month.

An earlier version of Ernie, back when people wore bow ties to check the IT systems

Ernie – which stands for Electronic Random Number Indicator Equipment – is responsible for drawing over three million prizes each month, worth more than £90 million.

The popularity of Premium Bonds has soared so much so that over 79 billion bonds are now eligible to win any of the three million prizes each month.

Premium Bonds were launched in 1956, with the hopes of 21 million bond holders across the UK and overseas resting on Ernie.

Ernie 4 will spend its retirement in Bletchley Park, home of the code breakers, after being handed to the National Museum of Computing.

The concept for the first Ernie was created there, by Tommy Flowers, builder of the code-breaking Colossus during the Second World War.

The way people can check prizes has also evolved over the years.

Customers can now check prizes through the official NS&I Premium Bonds prize checker Alexa skill as well as by using the prize checker on and downloading the official Premium Bonds prize checker app from the Apple App store or Google Play.

Chris Price
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