A HYDRO-ELECTRIC system which lay dormant for more than half a century is being revived to provide green electricity for the Duke of Northumberland’s estate.
A mixture of original and new equipment will use infrastructure in the River Aln, which was first put in place in 1889 and last used in 1948, when Alnwick Castle was plugged into the mains.
The refurbished original turbine is at the heart of the £105,000 scheme at Canongate Weir on the Aln in Hulne Park.
It is expected to produce a constant 25KW of electricity – enough to power 20 modern houses a day – for around half the year, or more than 100,000 units annually.
Graham Caygill, clerk of works at Northumberland Estates, said: “The idea was really from the Duke, he was interested in trying to get it working again.
“The first thing we did before committing ourselves was to strip the old system down and see if it would work. Derwent Hydro stripped it down and said yes, it will work.
“I was totally amazed. We say it was decommissioned in 1948, but it was actually walked away from in 1948. It’s stood the test of time – the condition of the plant was absolutely tremendous.
“The actual turbine – the bit that makes everything work – is original. There is a new gearbox to take on the modern equipment.”
The system works by channelling water along a short canal to the powerhouse, where it turns the turbine before returning to the river.
The plant has been fitted with filters to stop fish being sucked inside and river levels are controlled automatically. If the river drops too low, the hydro-system will automatically shut down.
Electricity produced by the set-up originally helped to power Alnwick Castle in the time of the sixth Duke of Northumberland. The cable from the river ran down Canongate, passed through the coping stones of the castle wall, then crossed the road at the Lion Bridge. The power itself was stored in a bank of batteries.
Mr Caygill said: “At the time when the castle didn’t have massive demand, it probably lit up a couple of hundred lightbulbs.”
The refurbished system, which is due to go live in mid-January after winning approval from the Environment Agency, will supply electricity to the estate’s workshops.
As a producer of energy from an environmentally friendly source, the estate will receive Renewable Obligation Certificates (ROCs), which can be sold to offset the project’s £80,000 cost and £25,000 connection fee.
Mr Caygill said: “The estate is keen to play its part in the cutting of carbon emissions by researching renewable energy options.”
The hydro-power initiative is the first of a wave of green energy ideas being explored by Northumberland Estates to cut greenhouse gas emissions.
“We are looking at other places now,” said Mr Caygill. “The weirs in front of the castle were put there by Capability Brown to make the River Aln look more majestic and make it wider and slower.
“We are looking at putting other hydro plants in there, using an Archimedean screw – a big steel water chute with a screw inside, like a big bottle opener. We are having feasibility studies carried out. There are also sites on the River Coquet we can probably use.”