I visited a nearby hydro project in Oxford today as part of some background research into Archimedes screw projects and learning lessons before the event rather than after.
Osney Mill is a historic mill and marina in private ownership and its owner, Tony, very kindly showed me around this morning. The mill is located on the River Thames and its weir has 1.9m of head. Two years ago Tony decided on implementing a hydro system at the same time as they redeveloped and extended the mill into city centre flats.
Here are the numbers:
The hydro generates up to 45KW and it provides power to ten flats, three houses, a forty birth marina and one Scheduled Ancient Monument (SAM)! The hydro also exports power, mostly in the summer, but utilises around 90% of the generated power in the winter. All the properties and the SAM have underfloor heating via air source heat pumps. The flats and the births are all metered. The flats are so well insulated that there is no further need for additional heating. The SAM is part of the old Osney Abbey and is used as a communal space for the residents.
A brilliant scheme and expertly project managed by Tony. The lessons were the importance of both precision civil engineering, getting the right project delivery structure and knowing all the risks from the onset.
More info on the scheme here: http://www.mannpower-hydro.co.uk/attachments/casestudies/osney-mill-job-sheet-1210.pdf