Off-grid Power


When I first installed the hydro turbine fifteen (!) years ago I cobbled together a temporary pyramidal doghouse cover from XPS to keep the direct weather off of it until I got the permanent housing cover made.  Over the years my incentive for making the new one was low as the old cover lasted much longer than expected. This past winter was the final straw as the old “temporary” cover started coming apart, so I commenced to begin the new, final one.  I took advantage of a heavy dew the other day, making me wait for my daily dose of mowing, to finally assemble the new cover.

I began some time ago with making a laminated arch using exterior grade adhesive and copious crown staples.  I then screwed on a section of Ondura corrugated asphalt panel roofing for the, well, roof.  The unit is light and stiff due to the corrugated arched construction.  Once installed I recognized an unintended benefit.  The corrugation makes it stiff, yes, but also acts as a sound diffuser on the underside reducing the sound to almost zero once I get more than a few feet away.

If the “temporary” cover using scrap materials lasted fifteen years, I can only imagine how long this one will be doing its job.

Now, back to mowing.

In The “First Time For Everything” Category

For the past dozen years I have been mothballing the barn’s microhydroelectric system once we get a few consecutive days with daily highs below freezing, usually in late November, then de-mothballing the system once we get to spring-like weather.  I learned a painful lesson the first year when I thought I could keep it running all winter long.  The result of that error was replacing 600 feet of spiral fractured 2-inch PVC line when the water inside froze solid.  Since following the newer strategy I mostly limp through the winter on the output of the solar panels.

As I reassembled the water line every spring, roughly a quarter mile of 2-inch PVC, and walk it top to bottom every year I would find some damage to repair, from ground upheaval (it is truly astounding how much the ground moves in the creek bed ravine over a winter here), extreme water flow during a heavy winter rain or snow melt, or (mostly) fallen trees.  Thus, my bringing the system online was usually a two- or three-day event.

Not so this year.  When I hooked up the water line from top to bottom, for the first time ever there was no damage!  Yes, a few of the soft joints had loosened and needed to be snugged up, no big deal other than getting pretty soaked, but other than that it was a couple hours of good exercise hiking up and down the creek bed.

Let the water and the electrons flow.

Scads of Helical Fracturing

The first of what eventually grew to several piles of thrashed pipeline.

For many years my seasonal regimen for the hydroelectric system has been fairly routine: I drain the waterline some time in November, depending on the temperature trajectory, then recharge the line sometime late in March.  I use the descriptor “For many years” because our first winter here also saw the coldest temps since we bought here in 2000 with overnight lows reaching -15F, and my dream of running the system year-round was dashed.  The water froze in the pipe, resulting in my need to replace almost 600 feet of pipeline the following spring.

At one time I was rethinking the scheme of having the pipeline above-ground and wondered, could I get it buried beneath the frost line?  Since the answer to that question turned out to be, “Of course, all it takes is something north of $75k, and oh by the way it will completely destroy your creek and everything adjacent to it,” I’ve just stuck with the original concept.

So now, every late autumn as soon as we get a string of days with sub-freezing daily high temperature, I shut it down to preserve the line.  Notwithstanding that I’ve had to do a little repair every spring, virtually all from trees falling on the line and breaking it (once was from a bear gnawing on it) the routine has worked well.

No big deal.  A half-day of work and we’re ready to roll.

Until this year.

The replaced section near the bottom of the system.

For starters, between travel and yard duties I did not even begin to turn my attention to the hydro system until a couple weeks ago, a full two months later than usual; since I have not been in the shop much and there has been plenty of sunshine, the solar panels did more than enough to keep things copacetic power-wise in the barn.

When I dove into it this week, I encountered almost two hundred feet of shredded pipe near the bottom of the system.  The damage was the typical helical fracture pattern of bursting due to water freezing in the pipe.  This perplexed me since I had drained the line last fall.  My annual draining protocol is to disconnect the pipeline just below the capturing box at the top of the system by loosening the hose clamps holding it together, then moving the pipeline aside a bit.  And that’s where the problem this year started.  To quote the famous LBJ line, “I reserve the right to be smarter than I used to be.”

Now I are smrt smarter than I used to be.

What almost certainly happened was a fierce rainstorm occurred after the disconnect, with the resulting water flow in the creek high enough to pour into the open disconnected water line and refilling the line.  And when the line subsequently froze, BOOM!  A couple hundred feet of pipeline turned into confetti.

Treacherous footing abounds. One false step can land you flat on a bed of rocks.

I spent this week working on the damaged area, which is an exhausting undertaking.  Every footstep has to be considered and calculated given that every single space is uneven, loose rock, most of it slippery from being in a creek bed.  Even wearing my best old lumberjack boots, it is treacherous.  Especially since it requires good vision to navigate the terrain, a feature I do not possess.  (Monday I will be having my 22nd eye surgery, which will provide no enhancement to my very compromised vision but should help to preserve what little vision remains in my used-to-be-dominant eye).  Trying to traverse treacherous ground with zero depth perception is a challenge.

I was able to make the repairs with the last of my original inventory of 2″ x 20′ PVC pipe.  When I had the first catastrophic winter damage I bought a complete bundle of the necessary pipe, I think it was 80 pieces, and have been using a piece or two every year since the first one.

Yesterday morning I walked to the top of the system and much to my dismay saw serious damage up there too – not from freezing but from destructive/tumultuous water flow in the creek — which I repaired fairly quickly, then reconnected the water line.  Just downstream from that repair I discovered another breach.  Drat.  Walking the line yesterday afternoon I found dozens more breaches, and hundreds more feet of shredded pipe.  Double drat.  The air was pungent with not-appropriate-for-Sunday-School epithets.

I went to the local farm coop and bought all the pipe they had but still I am way short.  This morning I will check with the hardware store the next town over.  I’ve gotta get enough material to finish the project next week and bring the hydroelectric turbine back on-line.

Remember the full bundle I bought ten years ago?  It was roughly $11 per piece.  Now the price is $36 per piece.  Ouch.

Lesson learned, albeit a very expensive lesson – put a $1 cap over the end of the pipe intake when you disconnect it, stupid.

Springtime Ritual #1 – Upstream Edition, Finis*

The end was definitely in sight.  All I needed to do was make the fitted lid with two layers of screen, window screen supported by 1/4″ hardware cloth and haul it the 350 yards to the weir dam.  Somehow I have misplaced the camera with most of the lid-making images.

It was very satisfying to see the unit all together, ready to get to work.  The only hard part of the project, really, was hauling it up the hill.  It is very awkward and though not especially heavy, it was not a feather weight either.  I actually strained a tendon in my left hand rasslin’ it up the hill but that is recuperating nicely.

Once I got it up to the top I had to spend some time re-configuring the creek bed since the new box is so different from the old Rubbermaid tub.  But when it went in place with a solid WHUMP! as it filled with almost 100 pounds of water I knew the this was just right.  To make sure it would stay put from either a rushing thunderstorm torrent or a rummaging bear I filled it with several hundred pounds of rocks.

The connection to the pipeline was a slip-fit gasket inside the shower drain fixture so I hooked it up and we were off to the races.

*Now all I have to do is make a new metal chute and it’s done.

Springtime Ritual #1 – Upstream Edition, Part II

With the dovetailed box sides assembled I moved on to attaching the board bottom.  The orientation of the wood there was such that it will cause the maximum swelling and thus compression sealing that panel.

My strategery was to lay down a bead of asphalt and screw thing down tight for each board.  I left each board over-length by about an inch to reduce the risk of splitting from the screws.  I left the end board even longer to allow for a more stable outrigger effect when sitting in the stream after installation.

The successive board was tarred to both the sides and the preceding board.  Tidiness was not the objective, sturdy durability and performance was.  My only real objective was squeeze-out.

When the bottom was in place I turned my attention to one of the side boards that had a bit of surface cracking.  I trowelled on some tar on that whole surface just to make sure it would remain intact.  Probably overkill.

A line of tar on the inside and outside of each corner completed the assembly.  Using a hole drill I installed the shower drain fixture that served as the connector for the penstock water line.

Now all I had to do was make the screen lid and haul the monster up the hill.

Springtime Ritual #1 – Upstream Edition, Part I

Not only was the severity of the winter weather manifest in the damage to the pipeline and master valve, the existing intake setup (pictured above) at the top of the system was thrashed.  The Rubbermaid tub was several yards downstream from the weir (dam) and the copper chute was missing altogether.  I cobbled the system back together to give myself a few days to make a new capturing basin.  The time had come to construct the collector box I have vowed to make ever since installing the system.

Using some of my prized c.1840 11/4 bald cypress lumber I made the box I have always wanted.  The first step was resawing the 11/4 stock into three equal boards roughly 4-feet long and eight inches wide for the long sides and a foot long for the ends, and the requisite number of cross-boards for the bottom.  I started the process by cutting the initial kerfs on the table saw, then finishing the task by hand (the lumber was too wide for my upstairs band saw.  I could’ve used the resaw bandsaw in the basement but would have had to move a whole lot of stuff to excavate it.)  Sorry, no pics for this process.

The boards were foreplaned as the finished surface.  Incidentally, even though the wood is 180+ years old it is still tacky on the inside when re-sawn and planed, and cypress’ typical smell of patchouli oil fills the air!  BTW I hate square-post-through-the-bench-top planing stops a la Roubo and always have.  I much prefer the right-angle stop in the leg vise as shown here.  It’s just how I roll, or rile, or whatever.

With the lumber prepped I set to cutting the dovetails in the corners.  As is my custom I cut the tails on both pieces at the same time.  Normally I nail the two boards together but this time I decided to tape them.

Another of my multitude of peculiarities is a dislike of sawing out the dovetail waste.  I just incise the shoulder, pare out a bit, then go back and wail on the waste.  In a minute or two they are done.  I cut the pins basically the same way.

The dovetailed corners were screwed together with decking crews (pre-drilled and countersunk) since adhesive was not likely to perform permanently under water.  With the screws and the swelling from the moisture I expect these joints to remain tight until forever.  Even so, before installation I slathered the corners inside and out with tar, just to make sure.

Stay tuned





Springtime Ritual #1 – Downstream Edition

Once I got the water flowing through the repaired penstock I trudged down to the turbine to check the result.  As I approached the turbine I was gratified to hear the soft whine of the mechanism, and exasperated by the sound of spraying water.  Once I got close enough to see, I noticed an absolute geyser of water spouting from the master valve that allows me to shut down the system to allow for maintenance (read: extracting fogs or crawdads from the nozzles).

So I hiked back up to the first soft joint — there are a half-dozen joints that are actually radiator hose from a bulldozer, held in place by four hose clamps (this method is designed to allow the penstock to blow itself apart without damage if there is an obstruction downstream) and disconnected it.  Yup, the master gate valve housing was split, big time.  There was no way to do anything except replace and re-plumb the business end of the system.  A hairline fracture I could possible deal with.  An eighth of an inch? Not so much.

I decided it was time to make some substantial changes to the water routing at the bottom.  as it happens I was in town, i.e. “over the mountain” on other business so I dropped into the farm supply store there to upgrade my valve system to a 2″ solid brass spigot valve rather than the low-tech, low cost, and low strength PVC sliding gate valve.

I also decided to take advantage of the opportunity of the completely disassembled plumbing to enact a longstanding goal of upgrading the system and complete the second line into the turbine housing, something I had been hesitant to do while the overall system was working well.  This upgrade 1) balances the forces on the impellor shaft by directing the water jet to strike the impeller from both sides, and 2) allows for a near-doubling of the wattage output as well.

For the connections between the new brass valve and the turbine housing I used new 1-1/8″ heater hose from the auto parts store.  The water pressure at the bottom of the system is 40-45 p.s.i so these flexible hoses should work just fine.

Finally, the new setup has me contemplating changing my strategy of mothballing the system over the winter.  Given the increased robustness of the new valve and the elasticity of the hose connections, why not just let the system run all winter long?  Water can flow well below freezing temperatures, particularly water within a pressurized construct (pipeline).  This feature is enhanced by particulates suspended in the water itself (the water coming though the pipe is very hard, essentially mineral water) so that fact alone would suppress the freezing point.  Thank you Mr. Auletta, my 9th grade Physical Science instructor, for 53 years ago relating the anecdote of the coal fields’ slurry pipelines that can keep on flowing until 15 degrees below zero Fahrenheit, or 47 degrees below freeing!  And, if I wrapped the bottom plumbing with heat tape to keep the smaller lines and the nozzles above freezing, couldn’t it keep running all winter long when our coldest temps are just barely below zero, and only for a few hours at a time?


Time to turn my attentions to the intake end of the system.

Springtime Tradition #1

The end of winter here in the Shangri-la highlands is accompanied by a number of traditions, not the least of which is the status assessment and repair/maintenance of the power system.  Sometimes this occurs as early as mid-March, but with travels back and forth to visit Li’l T and his parents and the deposition of several inches of snow as recently as last week, this year “spring” and its requisite duties is/are late in coming.

It is an undeniable truth that when you are “off grid,” a prominent blessing is that you are your own power company.  It is also an undeniable truth that when you are “off grid,” a prominent bane is that you are, well, your own power company.  Last week I split my time going over the mountains to get some service on my truck (I am old; I remember buying a complete set of new tires for my first car, a 1961 Ford Galaxy 500 with a trunk big enough to hold six feet of a 4×8 sheet of plywood, for $50 in 1970.  Now, two tires for my F150 are $500!   Sigh.) and working on the water line.

I walked the quarter-mile of water line last Sunday to gauge the level of repair needed.  Even though the winter seemed fairly ordinary judging by memory and the consumption of firewood, the condition of the hydro system penstock suggested a different history.

In six places the penstock was breached and fractured with classic helical ruptures as evidence of water freezing in the line.  This was surprising as I thought I had been pretty conscientious when mothballing (draining) the system in November, but the proof of the contrary is unavoidable.   And, this was not even the full extent of the damage to the system (more about that later).

I spent the better part of three days walking up and down the creek to make the repairs to the line itself.  I’m still sore.  I wound up grafting in about 80′ of new line, requiring 14 new joints.

As occurs every spring I spent some time refining the path of the water line to streamline it and increase its efficiency.  And still, every winter I must endure the damage that nature inflicts on it.

Is there a solution to this neverendingly onerous burden?  Sure.  All it would take is to find someone who could bury 1/4 mile of water line 48-inches deep in a mostly-solid rock substrate.  Finding that someone would be a challenge, finding someone to sign the check for maybe $125k is an even bigger problem.

Thus, I learn to embrace the responsibility of putting the system back together every “spring.”  There is a lesson there.  Whenever I face a particular challenge or hardship, I try ask, “Okay YHWH, what are you teaching me with this one?”

Winter Project – Solar Heat (?) for Scrounging BTUs

In a perfect world, 1) all the bents of the barn would be equally spaced, and 2) if #1 is not the case then the larger of the side bents, the one where my shop resides, would be on the south side of the building.  Alas, such is not the case.  When the barn was assembled and erected, what I got was what I got.  My shop is on the north side of the barn, and in the winter vis-a-vie the sun nary the twain shall meet except for perhaps three hours after dawn (east-ish wall) and four hours before dusk (west-ish wall).  As for the smaller space in the south side of the barn, the one ostensibly dedicated for a classroom, the solar/thermal gain is immense with full wall exposure to sunlight and a complete row of clerestory windows all the way around.  Given enough motivation I could probably move my shop there, but it is a smaller space and the heating stove is underneath the current shop, the classroom is entirely uninsulated…  I just had not experienced the alpine winters (near-zero lows are common) before setting up shop or things might be different.  Sigh.

Between my propane wall furnace keeping the overnight shop temps in the upper 30s for about $2/night (no real desire to heat more aggressively with it through the day as delivered propane is topping $5/gallon!), my kerosene heater (frankly astonishingly effective; I am pretty certain I could heat my shop with it alone for about $5/day, but that open flame thing…) and my wood/coal stove in the basement under the shop I can keep the temps congenial 99% of the time.  Nevertheless, my ongoing hunt for BTUs remains, well, ongoing.  The other day when it was single digits with a stiff breeze outside it was a challenge despite 3″ XPS insulation in the walls and ceiling, new tighter doors, and a relentless hunt for crevices to caulk.

Many years ago my friend Tred told me of a set-up whereby direct solar heat could be harvested and introduced into the interior space via a ducted “greenhouse” panel.  This video shows the concept.  My plan is to modify that construction to build and install a couple of solar thermal collectors, one on the northeast corner of the barn (near the vise end of my Roubo bench) and the other on the wall nearest my Waxerie at the other end of the shop.  For the former I expect I can harvest BTUs two or three hours each morning, and the latter perhaps four hours each mid-day and afternoon.  Any BTUs I can garner without ongoing effort is a winner to me.  A few years ago I made a solar oven to melt beeswax and it wound up melting the case for the digital thermometer (!), so I am optimistic that these units can be useful.

I think I just might start this project later today.  I’ll check to see if I have all the materials on hand that I need.

Winter Projects (and well beyond) – Harvesting Watts

Though I have been exceedingly pleased with my latest iteration of the hydropower capturing basin, a/k/a “Rubbermaid tub with a window screen” and its attendant weir flow sluice eliminating 99% of any debris build-up, a recent trip up the hill has revealed a fundamental shortcoming to the system — it cannot withstand a bear (?) attack.  The plastic tub-and-screen assembly was, to put it technically, knocked all whomperjawed.  The problem was temporarily resolved but now that it is winter and the system is mothballed for the season, the time has come for a more robust response to the travails of life here where there are plenty of big critters.

I’m thinking of fabricating a more robust wooden basin from some of my exquisite c.1840 cypress, designed along the same lines as the plastic tub and its screening feature but with the addition of long horizontal cleats on the underside of the box.  That way I can restrain the entire unit under a thousand pounds of rocks.  And it the megafauna tears that one up?  Hmmm.

I may also try to “straighten” the hydro line to allow year-round operation.  since water will flow in a contained line well below zero degrees F, there is no conceptual reason I cannot operate it here all the time.

Gotta noodle that one.

Plus, it is time to get going on the second water turbine that absolutely positively can run year-round.

Stay tuned.