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I would seek out Nigel Smith of

Sustainable Control Systems Ltd Unit 9 Wormbridge Court Wormbridge Herefordshire HR2 9DH

Tel: +44 (0)1981 551955 Fax: +44 (0)1981 550196 E-mail: info_at_sustainablecontrol_dot_com Just replace _at_ and _dot_ with the usual elements (I have done this to avoid Nigel getting lots of spam.)

Nigel makes the induction generator controllers and will have a lot of contacts in the industry and around the world I am sure. We used one of Nigel's controllers in DRC in 1993 and despite many lightning strikes leading to damaged transformers and IGC printed circuits board components reuirung replacements, the system is still working even though it produces a measly 1.5kW of power. That little bit of power makes all the difference to the hospital and staff houses, powering low energy lights, charging computers and phones and powering a corterising knife used in the surgery. The system is driven by a head of around 80m using a 7" Pelton wheel made by Gilbert, Gilkes and Gordon Ltd of the UK. The wheel has been replaced once due to being eaten away by the water which has some sand in it but it lasted nearly 20 years before being replaced. The piping was supplied by Pipeline Developments Ltd. We used 120mm SDR 11 HDPE piping welded using the hot plate technique. It's all still there buried underground and encased in concrete in places. The business end consisted of a 6hp squirrel cage induction motor out of a skip next I noticed one evening next to the UMIST labs (they still made me pay for it as the skip was on the way to the scrap merchants), we made the casing out of 1/4" steel plate and had it hot dip galvanised. Three threaded conical tubes were lined up to take the stainless nozzles we made in different sizes because the flow varied during the year and each branch had a 2" brass gate valve fitted. This arrangement allowed for the many unknowns faced by designing in the UK for a project site never seen and on which it was difficult to get meaningful data. The villagers, one of my graduates and I fitted the piping and the rest of the system over a 6 week period in 1993 and I got it working in the early hours of the day of my departure. They had to hold the light aircraft while I threw my stuff into my bags, said and said hurried goodbyes. I had spent the previous day trying to get it to work. Unsuccessfully. I went to bed thinking 'last chance' maybe there is air entrained in the pipe and it will rise up overnight. It did and the system worked a treat! What a close call that was!

One of the bits of kit you will need are load limiters that will really help you make your system sustainable. These are fitted at each property and limit the maximum load available, cutting out for two minutes if the demand exceeds the value of the device selected and trying again to see if the demand has reduced. This means that each user can select a supply value and pay a flat rate each month meaning there is no need for metering and calculations.

Another piece of kit you could use is a load shedder which monitors the frequency and drops loads off the supply in a priority determined by you/the installer.

You are welcome to ask me questions and I would be keen to be involved especially as it sounds like money is no object :-) (just joking) but if it was me I would talk to Nigel first. Mention me. He's excellent to deal with.

All the best!

Steve