Old Mill Ireland

Hi Guys, I am new to this forum and decided I would make anyone who was interested aware of my plans and maybe they could share their expertise on the matter. I have purchased an old flax mill site in Ireland and the previous owners had the water wheel scrapped for money which was terrible. Bits of the cast iron frame still remain on the site. What I plan to do is build my house on this site and the old building will have to come down as it is in poor condition and parts were recently renovated and no longer look like a mill anyway. I am very keen to get a water wheel reinstated on the plot and supply electricity to the house. The house itself will be connected to the national grid and the main reason I want the water wheel is to keep some tradition to the site. Now there are a number of things high I need to consider:

1. The current mill race will need cleaned in order to divert the water back down to the wheel. This won't be a problem however I am trying to figure out the best way to do this....do I pipe it all the way down where it is contained or do I bring it back down the mill race so far and the dam it up, almost like putting a plug in a sink with an overflow and have an extract pipe taking water to the wheel. I do not want a large volume of water not contained near the house for obvious reasons.

2. The existing wheel would have been in the region of 16feet by 3feet wide, of course I would love a 16ft replacement but these things are like hens teeth, so hard to come by. So how best should I know what size to reinstate or have built from scratch.

3. Now that he water wheel will be turning I want reap the benefits of this by hooking it up to an alternator to generate electricity. Obviously this will generate me DC voltage, where I need AC for my house. I do not want any battery banks. How do I size an alternator accordingly to the speed which can be geared off the wheel and is it possible to have this system running in such a way that it will meet the demands of the house and then in times of high demand I can automatically switch on to the national grid to meet the excess demand? Also on the flip side of things, if I am not home during the day and 3kwh is being generated constantly off a wheel and I have only a demand of 300w what will happen that excess electricity that is generated? Ps I cannot connect to the grid as connection costs for exporting are so high at the minute.

Anyway thanks for anyone who takes the time to read the following. I am considering doing a blog on progress but this would depend on the interest both for the wheel configuration and the house build.

Regards,

G

A couple of things to think about before you start

Firstly Gerard where are you ? as the Law in the North is NOT the same as in the Republic . What you are suggesting may require planning permission even if it an exsisting mill, talk to your local planning department . If you are in the UK this might be a good start https://www.gov.uk/government/collections/hydropower-schemes-guidelines-and-applying-for-permission In the republic http://bcdenergy.ie/renewables-hydro-power.php seem to know what they are talking about.
Secondly A lot is also going to depend on the flow of the water and the height of the fall . Can you get figures for these ?
If you dont want a battery bank ? You might be able to sell electricity to the grid (certainly in the North you can dont know about the Republic ) In effect use the grid as a battery bank. You may get a grant to connect to the grid if you are going to provide electricity Worth checking out
Good luck I am sure others more knowlegdable than me will speak up soon

David

David, in Northern Ireland. There should be no issues regarding planning especially on the basis that this is benefitting the heritage of this site. The only stipulation would be in the reinstatement of the mill race which needs cleaning our and the various issues surrounding habitat etc..on this particular site there is between 8-10m of a head over a distance of 250-300 meters. I would need to calculate the flow for you, however I had toyed with the idea of a hydro turbine and export excess to the grid however this is a very large capital expenditure. I had a specialist out to look at the site and it was specified for a 20-30kW turbine depending on the turbine house location.

The logic behind everything is straightforward however I would need to know certain specifics like what size of alternator to use and I guess that depends a lot upon the side of the wheel and possible potential. I guess my ideal scenario is that I generate DC voltage through the wheel wire that to an inverter giving me AC useable within the house saving on electricity. But I'm guessing I can only be either grid connected or stand alone.

Introduce yourself on the UK Navitron forum there are quite a few members on there who run waterwheels and can advise on the various rules regulations pitfalls etc. On the bright side if you do it right you should be eligible for the feed in tariff but again the forum is expert in that sort of thing.