SWH project part 16 - up and running

It's going! I'll be leaving behind a short list of outstanding finishing touches, and a couple of suggestions for future improvements, but in the meantime it's working: preheating the water for the laundry so the geyser doesn't have to work so hard, and thus saves fuel.

Solar Water Heater opening ceremony.  The first overcast day in ages, but was
actually just as warm and twice as humid.  Sweaty.

Some of my main helpers.

Re-fitting the heat exchangers (see here for why)

Lid back on after much intricate wielding of the hacksaw.

The brazing chap from Lahore was back doing some other work in the hospital,
so I got him to attend to a minor leak.

One last piece of colourful frazzled copper.

Snug as a bug in a rug about to chug a mug of... hot chocolate?  Glug!

SolarBot doing his thing.

Modest temperatures on a cloudy morning.  In the middle of a clear day the
panels hit 80°C, and the tank gets to 65-70°C.

Again, on a clear day the output beats 50°C.  This could be improved by
lengthening the heat exchanger coils, or by moving to a pressurised tank
with no heat exchanger.  The latter is almost certainly worth doing.  When
someone gets round to it...

Finished system.  For a given value of "finished".

Tank insulated and roofed.  Among the final touches I'm
leaving for the workshop guys to do at some point is to stop
the rainwater collecting on the platform and soaking into the
bottom couple of inches of insulation.  Preferably before the
monsoon starts in earnest.

Thermal expansion coupled with cycles of thunderstorms
followed by hot clear days has done for these strips we used
to hold down the glazing.  They'll replace them with some-
thing better and redo the seals...

(This one's an extreme example - the other nine seem to be fine!)

...which should hopefully stop this happening.  They'll also put some metal
sheeting along the top edge of the panels.

+/-

Looking forward to:

• Less than 30°C during the day.
• Sleeping without a fan at night.
• Internet that goes at a decent speed, works for more than 70% of the time, and for more than 45 consecutive minutes in any one go.
• Unrationed cheese.  Breakfast cereal.  Bread.  Pig!
• Smaller arachnids.  (No Gavin, that is not an invitation.)
• Seeing friends and family at home - and once again more or less understanding how social situations are supposed to work.
• A bit of a break.

Will miss:

• After a suitable break, the food.
• The exhilaration of no-rules driving.
• Interesting flowers and wildlife.
• Wearing these pyjama-equivalents all day.
• Painted trucks.
• Some great adventures in some fantastic scenery.
• Not having to look after all our own utility bills/paperwork.
• Friends we've made here, especially some wonderful people in the community doing similar work to ourselves.

Compound wildlife

A few pics from around the compound over the last month or two:

Interesting flowers.

Blue Tiger.

Tree Pie.

Yellow-billed Blue Magpie.  There were some of these nesting behind where the
SWH project is.  When a cat comes along they take it upon themselves to warn
the whole neighbourhood.  And then hound the beast out of the area by dive-
bombing it.

Looks like one of those glow-in-the-dark plastic beasties.

There are lots of young birds fresh from the nest at the moment.  This Indian
Myna hadn't quite worked out what its wings were for yet.  The other day we saw
a couple of adult Black Drongos encouraging their 3 sulky offspring to budge
off the wire they were determinedly clinging to and fly.  With little success.

One of our semi-resident bug catchers.

All that was left of a Common Peacock after some bird had had a large and
tasty snack.

And the underside.  I think I'd like a rug like this.

A beast of a bee.

Now this is a proper sized thistle!

Finally, a not completely blurred pic of a Paradise Flycatcher.
Its love of shady overgrown places combined with its hyper-
active nature do not make it an easy photography subject.
It's fairly amazing to watch hunting, with a fantastic hovering
ability, as you'll see in the 2nd half of the video below.  His
oddly unmatched mate is chestnut-y red and without the tail
streamers, but equally aerobatic.

Another beast of a bee.

Weekend away part 4 - stuck in the mud

For the next part of our adventure we decided to take a drive down this little jeep track descending into Gittidas - this large area of green pasture at the head of the valley.  As always, click the pics to view them full size - it's usually well worth it!

Looking down into Gittidas.

This little road was awesome, and driving down it was kinda hair-raising.  The
road-builders have obviously just rearranged the scree slope a bit, using the
stones they take from the left side to build up the right side like a dry-stane dyke.

Our borrowed Land Cruiser coped quite happily with rocks and streams...

...but was less happy when we discovered this bit was a little deeper and a little
more slippery than we had anticipated.  Jimmy and I did some experimental
attempts at going forward and back, and trying to get some flat stones under
the wheels.  Trouble was, we appeared to have driven off the edge of a sort of
ledge of harder ground, upon which our spare tyre and rear diff were grounded.
A couple of local guys turned up and we had a go at jacking up the back of
the car in another attempt at getting some stones under the wheels.  We gave
up and they wandered on.

This is where we started to wonder things like "how far back were the last
people we saw?" and "how many hours of daylight do we have left? and "how
cold do you think it gets here at night?"

Actually, there were a surprising number of people passing by.  We recalled
having seen a tractor working further back down the valley, so after a bite to
eat Jimmy (with his superior language skills) hiked off to find some locals.

In the meantime we weren't short of things to look at.  Several lone guys came
past at intervals, and enquired how we were doing.  Being the man, I had to do
the communicating guessing what they were saying and trying to explain that
yes we did have someone else with us and he'd gone down the valley to bring a
tractor.  One guy said we should get some wood to lever the back of the car up.

Suppressing my doubts about the likelihood of finding any wood in this tree-
less part of the valley, I followed him to some patches of scree where he thought
he might have seen some.  After a while of scrabbling around and moving rocks
back and forward, he declared/gestured that it probably under this patch of ice
and snow and would therefore be difficult to extract.  I thanked him for his help
and he shouldered his pack (which appeared to be full of animal dung for fuel)
and continued on his way.  Whether he had actually seen some there previous
time he was here, or whether he was just showing willingness to help, we'll
never know.

The rescue party.  After a bit of a hike, Jimmy came across these chaps, and
got chatting to them.  They told him some stories about all the people they'd
dug out:  "Oh yes, there was this doctor who got stuck and the jeep couldn't
get him out, and the tractor couldn't get him out, but then he paid us eleven
thousand rupees and we got him out!"

To which the reply was "I'm sorry, we don't have that kind of money".  After
settling on a flat rate of four thousand (just under £30) to get us out, they got
out their spade and walked back up with him.  (Jimmy had asked for more
than these four to help us essentially lift the car out, but that would have
meant sharing out the reward money between more people, so...)

Hard at work.  By this time it was getting kinda chilly for our summer clothes.

Free!

As we started our long journey back (5 hours including a stop for some
local chicken karahi at about 10pm - we'd lost 2-3 hours in the mud),
it started to get pretty.

Driving back down those roads in the dark was less hair-raising than you might
expect - a case of what's out of sight is easier to put out of your mind.  Further
down it had evidently rained a bit earlier, which made some sections a little
more exciting.

Last but not least, over the course of the day we had seen (and had to stop for) various flocks that the Gujjars were driving back up to the pastures.  But it became quickly apparent that they do much of their moving at night time - cooler and less traffic.  We'd just see a couple of little torch lights in the darkness ahead, then we'd be pulled over watching thousands of animals troop though our headlights.  In the video above, about 3/4 of the flock had already passed by the time I'd got my camera out.

There was some fairly amazing stargazing to be had up here too.  We made it back to Naran just before midnight, where the nightlife was still buzzing!

SWH project part 15 - teething problems

Temperature sensors

The day after I mounted the temperature sensors on the panels, we had a big storm.  Had this happened after we had put the glazing on, this would not have been a problem.  In reality, despite the sensors being encased in a large blob of silicone, the water managed to do some impressive capillary action where the wires enter the silicone, shorting out 5 of the sensors.  One of the sensors inside the tank also failed, though this was more expected. 12/18 still working!

Water tanks

The original setup made use of an old blue plastic water tank, which acted as a heat store (unpressurised) through which passed a couple of copper coils carrying the water to be heated.

System diagram - with heat exchanger.

Old blue tank with heat exchanger coils.

While the heat exchanger method was giving decent enough results, after a few days of sitting at 70-80°C, it became clear that the surface of the plastic was not responding well to the hot water, so we bought a new superior quality (allegedly!) tank to replace it.

This tank had the advantage of having a screw top, hopefully allowing us to seal the tank. This would allow us to run the tank under pressure with direct connections to the water supply, dispensing with the heat exchanger coils.   The larger tank will also run cooler, meaning lower heat losses and thus better efficiency.

System diagram - without heat exchanger.

In a separate issue, it was found that the pressure loss caused by all the additional pipework meant that there was no longer enough pressure for the washing machine's liking (it's a bit fussy!).  So we raised the height of the water tower supplying the pressure by another 5 feet.

Newly raised water tower.

Anyway, yesterday we sealed the top of the tank, screwing the top on tight with silicone applied to the screw thread.  After giving it a few hours to cure, I opened the valve from the water tower.  The tank ballooned out slightly as expected, then the top just popped off!  Inspection revealed no cracks or tears anywhere; the lid had apparently just stretched enough for the screw threads to pass over one another.

Recalcitrant lid (with air release valve and sensor leads), having just popped off.

So, take 2: this morning we strung a bunch of jubilee clips together around the edge of the lid, with the hope of holding the screw threads in a meshing position.  This seems to hold okay, but the way the tank bulges makes me nervous about its future longevity.

Bulging lid.  The rest of the tank looks similarly bloated.

I think we'll revert to the heat exchanger plan (assuming we can get the kinks out of the copper pipe).

Tank stand

A stand which was adequate for the 600l tank was not sufficiently strong for the new 1200l tank, with a couple of dodgy welds breaking. Fortunately we spotted one of the legs beginning to bend in time to avert a complete collapse, and the stand was then beefed up considerably with an extra central support and some proper diagonals made of some nice new chunky angle iron to stop it flexing.

Beefed up tank stand with new 1200l tank.

These problems partly stem from the way people are taught to learn parrot-fashion and the general low standard of education here - the guys have an idea what a structure should look like, but often without really understanding why you need to put a particular strut in a particular place. Hence you will end up with something which looks similar to a strong structure, without necessarily having the function of one.

Weekend away part 3 - Babusar Pass

On Sunday we set out on a little expedition to the top of the valley, some 70km away.

The first challenge was getting out of the car park.  The guys at the guest house
apparently only built it a couple of weeks ago, and are milking this little money-
spinner for all its worth by packing up all the available space.  Even though we'd
told them we'd be leaving early, they still had to go and wake some poor guy up.

There are many side valleys branching off the main one, each one would be
an adventure all by itself.

A view back down the valley, sometime after we stopped at a roadside eatery
for breakfast parathas and omelettes.

One of the better bridges.  At every river crossing there were concrete supports
waiting for a permanent structure to be (re)built, a diversion to a little temporary
structure like this one, and in some cases a little way down the river the twisted
remains of the previous one.  On most, the planks rattle and bounce as you cross,
on one the plates were misaligned meaning you had to slalom across it, but the
best was a tiny one about the width of the car, which you had to drive both on
and off at an angle.  Fun.

You know, parts of this look a lot like Scotland.  Only somewhat... magnified.

Looking up towards the pass.  After a while you get used to roads with no edges.

There are lots these settlements huddled in the base of the valley:  some of them
seemingly abandoned, others being re-inhabited by the nomadic Gujjar peoples
bringing their flocks (mainly goats, sometimes with a few horses/donkeys/mules
thrown in) back up to the summer pastures.  Some of them walk for two months
each way to/from wherever they spend summer.  The richer ones hire a truck.

Keep your thumbs out - the rocks make the steering wheel really kick.

Looking down the other side of the Babusar pass towards Chilas.  There were
a surprising number of tourists up here, in/on a surprising array of vehicles.  I
would not have liked to take a motorbike up those steep twisty gravelly rocky
roads.  It hailed.

The ground up here is festooned with all sorts of tiny little wild flowers - pink,
yellow, blue, purple, white, and even dark red, contrasting with bright orange
and green lichens on the rocks.

Cairns.  I think hills everywhere have these, but I've never come across such
geometrical ones.

Looking down from just below the Babusar Pass into the Gittidas pastures.
Click to view full size.