THE “sky high” electricity bill for a storage unit at Sharpness Docks led to the discovery that cannabis was being grown there, a court heard today.

It was when the roof of the container in the dry dock was the only one not to be frosted up on a chilly day that the illegal use was uncovered, Gloucester Crown Court was told.

Boatbuilder Jonathan Cresswell, 47, of High Street, Tredworth, Gloucester, had allowed another person to use part of the container for cannabis cultivation in return for being given some of the crop for his own use, the court heard.

Cresswell admitted permitting the premises to be used for cannabis production on March 13 this year and was sentenced to a 12-month community order with a 20-day rehabilitation activity programme.

Prosecutor Grace Flynn said Cresswell and a friend had rented the container from 2015 onwards.

In March this year, she said, staff at the yard became alarmed at the high level of electricity being consumed by the unit. They described the bill as sky high.

On March 13 the yard manager went to the unit and as well as the lack of frost on the roof he smelt a strong odour of what he believed was cannabis and called the police.

A search of the unit revealed it had a small fenced off area at the back in which ten cannabis plants were growing.

There was a sophisticated hydroponic growing system installed with heating, lighting and watering.

The defendant was interviewed and said he had allowed another man to use the unit in return for payment in cannabis.

Ms Flynn said there was no estimate of the potential yield of the cannabis but it was thought it would have produced anything between £2,800 and £8,400 worth of the drug.

Cresswell had made seven previous court appearances for 12 offences, some of which were cannabis related, she added.

Jason Coulter, defending, said Cresswell had hired the container to build an 'eco boat' - a project now nearing completion which he is hoping will be a big success and make his fortune.

The container was already fitted with a water sprinkling and heating system, he said.

Cresswell was a long term cannabis user because it helps alleviate pain from a shoulder injury suffered playing rugby, added the solicitor.

"The acquaintance mentioned, someone I suspect he had been buying cannabis from, saw an opportunity to requisition part of the container to grow the drug,” he said.

"My client is currently unemployed and on benefits but hopefully his fortunes will take a turn for the better in the near future when the boat is completed."

Passing sentence, recorder Don Tait told Cresswell: "The probation service will attempt to address your attitude towards cannabis. I am not going to lecture you about it. Whether they have any success, only time will tell."