Solar-PV Battery Charger

(Applied to Unst Market Gardens' operation, May 2013)

       The U.R.G.E. (and later the Unst Market Garden) project depended entirely for its survival on hill run-off water stored-up during wet times. Accordingly, a large collection-pond was dug out by the U.R.G.E. partners as a part of that project. Inevitably, size limitations on this pond meant that a good part of the collected water simply ran to waste in particularly wet weather, and was all too quickly used up in dry times. Also, the fact that the pond was at almost the lowest point of the U.R.G.E. plot meant that all of the water collected in it either had to be taken to the (many) points of use by hand, or pumped there by some means. This problem remained unsolved for U.R.G.E., although the idea of hammer-pump equipment was considered seriously at one point. Later, when U.R.G.E. came to an end and the Unst Market Garden project was initiated, a drainage channel was dug to provide water from this pond to the new site. UMG is several metres lower than the pond itself, which seemed to offer a possible free advantage.

       In spite of the height difference between the collection-pond and the storage tanks at UMG, it quickly became clear that relying on gravity alone to do the work wasn't going to be a solution. The main reason for this was that a syphon couldn't be established and maintained without installing some fairly fancy plumbing. A number of ideas were considered for pumping this water into storage containers on the Unst Market Garden site. Nearly all of them were discarded as being too expensive and/or too unwieldy and impractical to implement. My initial suggestion on this problem was that 12V submersible pond pumps and car batteries would probably be the cheapest, easiest, most reliable and least high-tech way to provide such a facility. Sarah implemented this idea more or less straightaway, and as a result now has the means to buffer-store about eight tonnes of water. At the same time, she installed pipework into the main tunnel so that water is now on-tap at all times.

       Needless to say, the car batteries that provide the power to run this setup regularly (and all too often) had to be lugged back and forth over several hundred metres of very rough ground to Sarah's house for recharging. The long-term orthopaedic risks of this kind of operation were all too clear to me, as someone who'd used up all of his luck in that direction a long time ago; so I decided to try to find a way to re-charge those batteries on-site. A quick hunt around on Amazon and then eBay turned up the required item: all that remained to be done then was to install it in a suitable location - on the side of a south-facing shed in the middle of the UMG site, as it turned out - because that spot receives direct insolation during the whole day, all year round. The finished installation looks like this:

       The panel's supporting frame was made from a nice little chunk of recycled window-sill wood, salvaged from a recent SIC property-upgrade exercise carried out on Unst. The angle of tilt ensures that the panel is more-or-less flat-on to available incident sunlight during the six months on Shetland when insolation is at a lower level.

       The processor-based smart control panel is fitted inside the shed out of the weather, and looks like this:

       The whole thing was simplicity itself to install and set up; and at the time of writing (May 2015) appears to be doing its job properly and unobtrusively. In my honest opinion, it was (and continues to be) a jolly good £50-worth. You may be able to view it online by clicking here.

PROJECT REQUIREMENT:

To create a supporting web-page for Sarah McBurnie's
'See Shetland Tours'
mini-bus Shetland sight-seeing tour operation.

(Ongoing project)

Basic design:

Derrick Hales
Financial Planning
(Web-page alterations)

PROJECT REQUIREMENT:

To correct, improve and extend an existing web-page, to advertise more effectively a range of Financial Services.

(Ongoing project)

Basic design:

Realisation / layout:

Self, after discussion with the client.