The set up

The set up
5.46mm jet delivering 0.68 l/s to the pelton which is rotating at 900 rpm and generating 135 watts into the grid.

Sunday, 19 February 2017

Yet more on moisture

Dealing with the problem of moisture in the electrical side of my Powerspout is proving more difficult than I'd anticipated.  A year ago I started putting bags of silica gel in there in the hope I could create a warm, dry atmosphere. I also blocked off the ventilation louvres to stop moist outside air exchanging with the dry inside air.  But it hasn't worked out as well as I'd hoped.

Initially the strategy seemed promising; relative humidity in the compartment could be got down to 10% (ambient outside being in the 90's) and the lack of ventilation made it warm but not too hot. The warmth did have the disadvantage of reducing electrical output slightly but the reduction was only by 1 watt per degree Centigrade rise and I came to accept this as a price worth paying.

What has become evident in the longer term is that the silica gel doesn't keep the absorbency it had when first purchased; it cannot be re-charged to be as good as when new; I have been re-charging it by putting the bags of beads in a fan oven at 120℃ for 2 hours, but even prolonging the time to 3 or 4 hours doesn't seem to drive the last 7-8 mls of water out of each 100g bag; in consequence, when put back in the SmartDrive housing they only last for 3 weeks before needing to be re-charged again. 

More recently I've tried a new tactic: if a compartment is COMPLETELY sealed it ought to be possible to get the relative humidity down to a low level where it will stay; but the sealing does need to be thorough: ALL possibility of moist outside air exchanging with dry inside air needs to be removed;  to achieve this for the electrical side means blocking two openings in addition to the louvred ports which I have already blocked: the drain hole on the floor of the compartment and the notch in the bearing block. The notch is there to allow any water getting past the seal on the shaft to dribble down, and so not come close to the outer shaft bearing.

But though plausible in theory, this tactic doesn't work in practice; admittedly I haven't blocked the notch in the bearing block because it's tricky to do, but plugging the drain hole seems not to have done anything to extend the period before the silica gel needs replenishing. This is disappointing. The drain hole gives direct communication with very moist air and spray from beneath the pelton; blocking it ought to have produced a benefit.  That it hasn't leaves me scratching my head for the next bright idea...

Saturday, 11 February 2017

A special day.

This week an Energy Expo has been held over 2 days at a nearby town; it is a yearly event and is billed as being "The renewable energy event for farmers and landowners".  As part of the exhibition and conference, an evening dinner was held during which awards were given to "recognise and celebrate the achievements of UK farmers within the renewable energy and low carbon sectors".

Schemes could be nominated by anyone, - self nominated even, but had to have been operational and efficient for at least 12 months; there were 6 different sectors covering all the main renewable technologies, one of which was hydro; entries would be reviewed by a panel of judges and shortlisted schemes were to be contacted a week before the dinner.

Well, I was reading all this some weeks ago on the very day when the window for nominations closed, and I thought "Why not ?" - and at the awards ceremony on Wednesday, I learnt I'd struck lucky !  I think it's the first time I've ever won anything !

There's a lot in the news at the present time about "fake news", so just to prove this is genuine, here's the photo to prove it !

L to R: Dulas Director of Marketing and Sales; myself; Energy Now CEO.

Many thanks to Dulas, a business which is based here in Wales, for sponsoring the hydro award; they make an excellent product (amongst many services offered) called AquaShear which is a screen for removing trash from the water going to a hydro turbine.

...and many thanks to Energy Now Magazine who stage the Energy Now Expo and Conference each year, - and in the process also raise money for a charity which helps farmers when extreme weather knocks out their farming enterprise.

All in all, it was a most enjoyable and special time, - a time which showed that Powerspout hydros can carry the day.

Tuesday, 31 January 2017

More on monitoring

Over a year ago, I was contacted by a Meter & Monitoring Services company who were keen to add a hydro installation to the range of sites they were already monitoring.  At the time, I couldn't see that the data they collected, or the way they collected it, would add to what I was doing before.  But one year on I'm rather impressed by their system.

Their set up involved installing a second energy meter in series with my existing kWh meter;  the new meter collects and stores generation data and once per 24 hrs transfers it over a mobile phone link to my 'account' held on a central server; by logging into this 'account' I can view all the data and down-load both the raw data and the graphs which the data make possible.

'Smart' meter and circuit diagram in the required G83 format

This is the record of generation since 1st Oct 2015 to today 31st Jan 2017 as logged by the system:

...the vertical scale shows kWh generated per day; a point of note in this record is how little generation there has been in Dec / Jan 2016/17 compared with 2015 /16; the present daily yield is just 8 kWh per day whilst last year at this time it was 18 kWh, - testament to how dry this year has been.

The advantages of this system compared with what I was, and am still, doing are that it is automated, more accurate and more secure.  My old system takes data from the inverter (which is less accurate than this 'industry standard' energy meter); requires me to take it manually each month (whereas this needs no human input); and requires me to keep it on my computer (whilst this system uses 'cloud storage').

All in all, I think it's quite a useful addition to the way I monitor my Powerspout... especially since for me it's free, - though that might change. But take note - it does require mobile phone reception.