Plans for hydro-power station on banks of the River Derwent revealed

A conical structure rising from the banks of the River Derwent could be powering Derby's Council House by 2010.

The building, planned by the city council, will house a £1.66m hydro-electric power station that will pump 46.8m litres of water an hour from the river to generate energy.

A planning application is about to be submitted and the Environment Agency is considering whether to allow water from the river to be used.

If both are approved, the power station could be built by Longbridge Weir and operating by April, 2010.

Councillor Lucy Care, cabinet member for planning and transportation, said the plant would make use of sustainable energy opportunities.

She said: “The Council House it is sitting there by the river, near a weir, and it is stupid of us not to be using it.”

The structure will be covered in climbing plants and be accessed by swirling ramps around its outside so it can be used by disabled people.

At the top, there will be a platform for people to look across the river and a bridge linking it to the Riverlights development of restaurants, hotels, a casino and a bus station.

Inside are the generators and equipment which would pump water out of the river and push it through turbines to generate power, which would then be transferred to the Council House via cables.

The building, which is preparing to undergo a multi-million-pound refurbishment, may sometimes have to draw extra electricity from the National Grid.

But at other times, particularly in the evenings, it will use less energy than the station will produce, meaning it can sell the extra to the grid.

Once up and running, it is expected to bring in around £128,000 a year.

However, with costs of more than £1.6m and running costs of around £20,000 a year, the authority has estimated it will not pay for itself for the first 25 years. The council's annual energy bill is £85,000.

Mrs Care said those estimates, made at the end of last year, could already be superseded.

“The cost of electricity is rising all the time, with soaring oil prices, so the pay-back period of this power station is getting closer,” she said.

“We need to get this going as soon as possible so we can set an example to other people and businesses about what they could be doing in terms of helping the environment.”

Original proposals for the power station were for a single-storey brick building, costing around £1.5m.

But the authority has invested a further £160,000 to make the building more attractive.

The generator, which converts the power of the moving water into energy, would be relatively quiet and difficult to hear over the sound of water running over the weir.

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