Itteringham Mill micro-hydro-turbine went live at the end of November 2006.  The turbine will effectively make the Mill self-sufficient with regard to electricity and, if a heatpump and underfloor heating is installed as planned, eliminate the burning of oil for central heating.  Other green plans in the pipeline are for solar hot water.

The turbine produces a peak output of 5kW,  However local conditions in the river (volume of flow, amount of weed growth, capacity of the river immediately downstream of the turbine) currently restrict output to a maximum of 4.7kW, and more regularly we achieve between 3.2 and 4 kW.

The installation was the culmination of 2 years of planning that started with Derwent Hydro carrying out a feasibility study in late 2005 and recommending a siphonic turbine in a new culvert next to the mill by-pass weir.  The Environment Agency awarded a licence for the work in early 2006 and the local authority gave planning permission shortly thereafter.  We were also required to invite Norfolk Wildlife Trust to the site to investigate the presence of water voles and to recommend actions to mitigate the effect of the civil works on the water-vole population.

The design and fabrication of the new culvert was a bit of a headache particularly as local contractors estimated civil works would be an additional 40% on top of the capital cost of the equipment, which would have made the whole affair very uneconomic..  Luckily Lis's brother Charles had contacts in the steel fabrication business and we were able to have a culvert made in 3mm stainless steel for a much more attractive price thanks to Jeff Curtis of George Green and Co.  This was installed in August 2006 with the aid of local digger wizard John from Lloyd Coles Plant Hire, steel fabricator Brian Alexandra (who had actually made the culvert and driven it down from the far north), Charles Freeman (Lis's brother) and myself.

John dug the hole leaving the river bank intact one day, and in the evening we laid a bed of levelled peagravel in the base.  The following day Jeff arrived with the sections by 11:00am and they were manhandled to the site, craned into place and bolted together. We put a stop log across the entrance of the culvert to prevent mud being washed in when the bank was removed.  With everything bolted together and beautifully level we gave John the order to remove the river bank.  "Won't it float?" he asked, but unfortunately not in a demanding enough tone.  Of course, it did!  A brief moment of panic as we stuggled to remove the stop log and let the water in unhindered then it settled back down - but regretfully not as level as it had been before.  Too late to do anything about it now, so it continues to offend my eyes.