This all-electric facility is equipped with solar panels and heat pump technology, and is strategically located next to the maximum security HMP Full Sutton.

HMP Millsike features 24 workshops and training facilities aimed at rehabilitating offenders, managed by Mitie Care and Custody, with educational programs provided by PeoplePlus.

The government asserts that this new capacity will enhance public safety by allowing more violent offenders to be incarcerated, thereby preventing future overcrowding issues.

The UK government has inaugurated HMP Millsike, a pioneering 'green' prison in East Yorkshire, which adds 1,500 new prison places to combat the overcrowding crisis in England and Wales.

As part of a £2.3 billion ten-year prison capacity strategy, HMP Millsike is one of the largest jails in Britain and is included in a broader plan to create 14,000 additional prison places by 2031.

The opening of HMP Millsike follows a period of early prisoner releases, where some inmates served only 40% of their sentences to alleviate space constraints.

Justice Secretary Shabana Mahmood has emphasized the government's commitment to reforming the prison system, stating that building new facilities is part of a comprehensive strategy to address crime and public safety.

Currently, many prisons in England and Wales are overcrowded, with some operating at nearly double their intended capacity, raising concerns from advocacy groups like the Howard League for Penal Reform.

The backlog in the crown court system has reached 74,651 cases, with projections indicating it could rise to 100,000 by the end of 2029, underscoring the challenges facing the judicial system.

A recent review highlighted that the prison population crisis is largely due to a historical emphasis on strict sentencing by successive governments, despite evidence that harsher sentences do not effectively reduce crime rates.

The opening of HMP Millsike has also created approximately 600 jobs, according to the Ministry of Justice.