Monday, November 23, 2015

Solar Washington, Part Deux.

Why should a solar installation be a one-time thing, and why would one have one 2160 Watt Array, when you could compare it to another 2160 watts of of solar right next door, but using different technology in a different manner?
Our 2015 project involved assembling 400 square feet of solar atop a sturdy steel frame, once again courtesy of Boeing Surplus Sales.  The clearspan structure was built from thirteen 20' sticks of SuperStrut steel channel, literally a big boy's erector set!  There's no substitute to vastly overbuilt when it comes to amateur engineering, as each of those sticks could support 5000 lbs!

The modules came from electric vehicle co-conspirator Matt Moreno, who has limited area with solar exposure on his home, and decided to upgrade from these Kaneka 60 Watt thin film modules to the Iteks that dominate our Made in Washington market.  These thin film modules are sometimes superior in our low light conditions, and the panel has complete coverage with active material between the frames, with no gaps as appear on mono or poly crystalline modules.  Thin film can outproduce crystalline during diffuse, indirect or the low-angle sunlight that we often have here in the cloudy northwest.  However, in terms of annual production per square foot, crystals are where its at.  So, I got 32 of these at depreciated and friendly pricing, plus found six more new-old stock modules to square out the array and stock two spares from a depressed "Prepper" who never put them into use (which doesn't matter much because the world didn't end after all).

In order to not be too obtrusive on the neighbors and to maximize my covered storage space, (at the cost of  8% less annual production than optimal tilt of 34 degrees). I set this array at the minimum 6 degree angle required for drainage, and came up with a mounting method that made the roof rain-tight using continuous strips of aluminum to bridge the longitudinal gaps, and the steel channel frame catches rain from the horizontal gaps and channels it to either side.  Like any simple shed, there is still dewfall below, but it is an improvement over sun and direct rain.  Note that optimal tilt does not equal latitude here in the cloudy PNW.  Most of our insolation comes during summer, so optimal tilt is biased towards summer production.

It was a nice bit of luck (that I pushed, of course) to get two arrays of the same rating; 2160 Watts from 36 Kanekas and 2160 Watts from the 8 Iteks!  But wait, there's only one inverter, isn't there?  Well, to maximize the state incentive scheme, I'm switching the Iteks over to Made in Washington Blue Frog microinverters, which apply maximum power point tracking to each single module in the array while producing grid-tied 240 VAC at the array.  Normally this would be overkill on a dual-axis tracker, but my modules do see some shade in the early mornings and late afternoons, so this will squeeze a few more electrons out of it.  This approach also fits into the theme of comparing technologies, and it will be interesting to watch the performance under different conditions and over different timeframes, as well testing as the long-term reliability of each.  This will also allow reuse of both the AC and DC wires already passing under the lawn, without expensive rewiring.

Solar Washington

It is often feared and now well-shown that electric vehicles are a gateway to other subversive activities, such as a drive towards energy independence.  With that in mind, I started solarizing the Donnaway homestead last year.  Never one to choose the simple solution or pay retail, I found an orphan, the overbuilt WattSun 1200 dual-axis solar tracker, which was discontinued after a corporate takeover, but I can hardly blame them, as the falling price of panels no longer justifies the added cost of a mid-size tracker.  It's usually cheaper now to get more production with more fixed-position panels than to point them properly at all times.

This tracker was an orphan because the original owner accidentally encroached on his property line with it, which was discovered during a pre-sale survey.  So, I got a bargain and learned the technology through manual dis-assembly and reassembly.  Part of the deal were 18 12-Volt nominal panels, which I saved for an off-grid application and replaced those 1835 Watts worth with 2160 Watts of Made in Washington Itek 270 Watt modules.  These eight panels will pay off better due to the state incentive structure.  Construction didn't commence until mid-summer, and final electrical inspection was accomplished on 12/28/2014, just in time to cement my tax credit!

PapaJoe Donnaway assisted in the engineering as we set sixteen feet of 8" steel pipe into a six foot borehole, six feet deep and six feet across.  The pipe was good galvanized Schedule 80, but a Boeing Surplus bargain, having spent its first 20 years as a parking stop..

We poured a whole pallet worth of concrete mix, applied in the following lifts:
First, a 6" floor with rebar threaded through the pipe base, topped by 2' of  native gravel and cement mix, then another 6" of  rebar and concrete, topped with another 2' of  "localcrete" and another slab, then topped off with the cobblestones that I had dug out of the hole, for a natural but weed-resistant and heavy base.


In addition to two wiring conduits that I trenched in at a good 36" below the back yard, I ran a 1" water pipe to a frostproof hydrant n order to have both water and power on the far side of the yard, and all the way back to the spa house.  Kind of a long round trip, but the water doesn't care.
Like many summertime construction projects, I kinda pushed the schedule on this one, and was working on it right up till the end of the year...


Tuesday, November 17, 2015

Sylvester Signs a Sponsor!  

Longtime friend and fellow eCo-Conspirator Tracy Farwell has seen fit to invest substantially in Sylvester's rehabilitation through his Better Energy, LLC. enterprise.   Better Energy seeks to bring about change in light and medium-duty truck fleets by repowering mid-life delivery trucks with proven battery-electric drivetrains.  Most EV conversion efforts have been short-lived due to their pursuit of extremely expensive AC drivetrains and their attendant complexity.  Better Energy believes that a simple series-motored BEV is the key to maximized economic utilization, and a far more attractive equation when paired with a local delivery truck that may not do many miles per day, but delivers lousy mpg, noisy and noxious onsite impacts, and is maintenance-intensive.  A battery-electric truck with a modern lithium-ion battery pack and a basic drivetrain make a powerful and affordable combination.

The classic Grumman Kurbwatt with an upgraded battery pack will demonstrate this concept at the small end of the scale, while John Lussmyer's electric 4WD Ford F-250 MegaCab Longbed amply demonstrates this concept in a very popular package.

Thank You Tracy!

Introducing Sylvester

As a result of my EVangelism and attempts to mentor EV newbies in the local area, I received the donation of a very special vehicle; a pristine 1983 Grumman Kurbwatt postal truck, one of only fifty built.
Here's the story if its creation, courtesy of www.kurbwatt.com.


The Electric KurbWatt and Gasoline/Diesel KubVan were the United States Postal Service's answer to the 1970's Oil Crisis. The Electric KurbWatt and Gasoline/Diesel KubVan were designed to save the United States Postal Service 500,000 gallons of fuel per year. The Electric KurbWatt and Gasoline/Diesel KubVan were ready for mass production, and was being tested by the USPS by 1983. The KurbWatt, and the KubVan were to replace the converted army jeeps that were used to deliver the mail door to door. The KurbWatt and the KubVan have the same mail delivery capabilities as an army jeep, but would save the USPS 500,000 gallons of fuel per year. The Electric KurbWatt, and the Diesel/Gasoline KubVan are the only vehicle to pass all of the USPS endurance tests. The KurbWatt and the KubVan were not mass produced because they were determined to be too small. The USPS needed a vehicle in a hurry, so Grumman designed the Long Life Vehicle (LLV). The LLV was larger, but got the same fuel economy as an army jeep. No fuel was saved.

Somehow, one of these wound up in the Washington State Dept of Transportation Fleet, where it was well-cared for and received an upgraded GE motor, larger than the original 7" Prestolite, as well as an upgrade to 156 Volts and a compatible Curtis controller!  A nice handwritten note from the WSDOT mechanic accompanied this trucklet into private hands at the surplus sale.  After two private owners, the Grumman was sitting in the weeds with a dead house battery and unknown other concerns when offered to me.  Thankfully, it turns out there were few other concerns, as the traction battery pack still had some life in it, being a bunch of Deka Dominators that were salvaged from a crashed Solectria Force.

It took one day to resurrect the Grumman and give some test drives, winning school district consent for the idea of training high school auto shop students in EV basics.  Sylvester, as we'll call him, has a five speed 1983 VW Rabbit front end, and a VW Dasher (Passat, Audi Fox, Audi 80) rear axle.

First order of business is making sure the binders are good, so off came all the wheels, and as usual, removal of the rear brake drum cylinders  resulted in a rounded-off brake line nut and we had to replace the hard line.  This was an excellent educational activity that will certainly result in safer stopping!







Lets Meet Tweety

After years of preaching the EV gospel at work, which had already resulted in the installation of three public charging stations and my boss buying a plug-in hybrid Ford C-Max, I succeeded in convincing Sumner School District to add an electric vehicle to its operations.  We settled on an EZ-GO burden carrier from Boeing Surplus.  I had been watching for a while, and scooped up a bargain that had lived life indoors and had a fairly fresh battery pack, in addition to a newly-replaced motor.
The name just seemed to fit, given that tiny body and big ol yellow head.
Tweety's no lightweight, however.  With 360 lbs of lead-acid batteries under the bed, a heater and fan in his head, a one-ton carrying capacity and 6-ton towing capacity, he came ready for work.

However, the intended mission didn't work out.  Seems that our district mechanics, after years of driving a sickly gas golf cart, wanted something more macho, claiming that they couldn't fit inside, and a diesel Kubota 4x4 would be much better suited for the job of topping off fluids and jump-starting school buses.  Never mind that burly Boeing machinists had used this cart for the past 22 years, and it is a twin to what hauls injured NFL players around!  Ever one to rise to the challenge, our 7 foot tall Director of Athletics folded his size fourteens up against the go-pedal, and said "Guys, this would be great for the Stadium- can we take it?!"  All parties breathed a sigh of relief, and Tweety now hauls ice and trash and tows sweepers and rakes to groom turf in far greater comfort, style, and cleanliness than the old diesel gator that he replaced.   And the mechanics?  They got another gas golf cart without a cab...  Just Sayin'