A Briton living in the US who plotted to kidnap, rape, kill and eat children has been sentenced to serve 27 years in prison before he is deported back to the UK.

Authorities last year found a dungeon, homemade child-sized coffin, butchering kit and torture tools at the Massachusetts home of Geoffrey Portway, who had engaged in online discussions with others about a mutual interest in abducting and murdering children.

The 40-year-old, who pleaded guilty in May to solicitation to kidnap a child and distribution and possession of child pornography, was jailed for 26 years and eight months. Under the terms of the plea agreement, the US district court in Worcester had to sentence him to a term between 216 and 327 months in prison, before he is deported to the UK.

Many of the conversations which Portway engaged in online involved the trading of child pornography, including images of injured, mutilated and dead children. There were discussions of the desire to sexually abuse, murder and cannibalise children in the pictures.

Portway, worked in the IT department at a US wholesaler, solicited several people for their help in abducting a child, predominantly Michael Arnett, of Kansas, and used Skype to communicate with him. Over a period of months, he repeatedly solicited Arnett to kidnap a child for him, with the intent that Portway would ultimately rape, kill and eat the child. These solicitations included discussing real children, by name and photo, whom Arnett claimed to know and have access to.

Portway and Arnett discussed different ways to kidnap children and the age range that Portway preferred, the court was told. Portway was told that Arnett had experience with the abduction and sexual abuse of children, it was said in evidence.

Portway's defence team attempted to claim during Tuesday's hearing that he had immersed himself in a fantasy world on the internet. However, prosecutor Carmen Ortiz described him as "the real deal" and said that the evidence was there that he was going to kill a child. "He can only claim fantasy here because he hadn't done it yet," said another member of the prosecution team, Dawson Belf.

On 27 July last year, federal agents along with state and local police executed a search warrant at Portway's home. Computers and digital devices containing his child pornography collection were seized, as well as the computer he used to trade child photography and attempts to plan the abduction of a child.

Agents also discovered a locked door in the basement. Inside a second door was a dungeon lined with sound-deadening material. It contained a chair, a television and what appeared to be cable access to the internet. The room also contained a child-sized homemade coffin with exterior locking devices, a steel cage approximately 3ft wide, 2ft high and 4ft long, with multiple locking devices, and a steel table top with steel rings at six points, presumably for restraints. Outside these rooms were a cabinet freezer, an upright freezer, disposable scalpels, butchering kits and castration tools.

The dungeon was described in detail by Portway in recovered chats as a place he intended to use to keep kidnapped children while he sexually abused them and as a place to eventually murder and cannibalise them.