Sun hours

[bcroe]

Here a 6 inch gap has been added between the upper and lower
panels. Snow will only need to slide half as far to clear a panel, and there will be only half as much
snow being pushed into each pile on the ground. That means I won't be doing so much running the
snow blower to keep the pile lower than the bottom of any panels. And pushing snow off will be a
lot lighter work; possibly avoided completely on some occasions. This would work even better if
the panels were turned landscape. But that would be much more difficult, and will be postponed
to another phase. Bruce Roe

As the white stuff did its last Mon and Tues, the snow slots again proved their worth. This morning
panels with a 6 inch gap were already 97 % clear. The one test section with a 4 inch gap was only
about 60% clear. I extrapolate that without a gap, I would have a lot of snow to move. Bruce Roe

[azdave]

I extrapolate that without a gap, I would have a lot of snow to move.

I hate to extrapolate snow. That's why I moved to Phoenix.

[Mike90250]

Thought I'd piggyback onto this. While doing irrigation research, came across this page of daily solar log for farming

http://www.cimis.water.ca.gov/SpatialData.aspx

Your state may have a like program.

[bcroe]

Its up, a 24 panel tilting array. The original PV array here was a classic SW desert system, which was FAR
from optimized for northern IL operation. After 4 years of observations and measurements, the new design
is an attempt to correct a number of problems.

The newest array is accurately positioned, and located to avoid previous shadows all day long. Physical
accuracy of the array itself is high. It mounts 24 panels of 250 watt rating, or 6KW.

Observations over days and seasons have been made, including with test panels. This input has been
used to attempt to maximum summer hour production over the entire day. This will be somewhat less
effective for other seasons, but variable tilt will allow some compensation. Existing arrays will be working
with this one.

The array is 12 panels wide and only 2 panels high, landscape orientation. This will greatly aid in allowing
easy tilt adjustment. An 8" gap between the upper and lower panels provides a space for snow to drop
through, combined with low height, to ease the labor of snow removal. Tilt bearings placed in the gap are
close to the center of gravity, minimizing tilt effort. 40" ground clearance minimizes or eliminates the need
to relocate snow piles from the panels. In case of a snow storm the array could easily be set to vertical, to
minimize snow pickup.

This array is designed to track the ground 10% slope along its length. No extra earth leveling, moving, or
"steps". The chain running across a picture was to keep my equipment from sliding down the hill while
working. The foundation contains 240' of rebar, with 6 pairs of front and rear supports joined 4' below
ground level to eliminate frost heave. Machine roller bearings can be greased.

I don't expect to change the tilt angle very often, though a couple of electric actuators are available. To
keep things steady the rest of the time, extra braces are bolted on at the bottom.

The wiring isn't on yet, hope I have enough to reach the 12 position combiner box nearly 200 feet away.
A 6 gauge ground wire runs with the panel wiring.

My considerable net metering reserve was useful this year. My well sprung an internal leak, causing
enough loss of pressure to run the motor continuously. I didn't realize it for weeks, my reserve is gone,
its all been renewed now. Net metering starts again on 1 April.

Bruce Roe24Rebar.JPG 24FouPosts.JPG
24FEast.JPG
24EndFr.JPG
24Rear.JPG
24ReSiSec.JPG
WellRepr.JPG

[SunEagle]

Very impressive Bruce. I wish you well with that new panel tilting system.

[Mike90250]

One of the few remaining phone booths !

[bcroe]

One of the few remaining phone booths !

That booth is in A1 condition, from Estes, CO. I got it after spending much of my career (but
not all of it), 41 years designing phone office equipment. Still looking for a rotary dial pay phone
at an affordable price. Bruce Roe

[CharlieEscCA]

It looks like a well engineered solution -- but I'm trying to wrap my head around cost vs payback of changing tilt a few times a year.

And on the telecom career, Western Electric, Bell Labs, GTE Automatic Electric, or ???

[J.P.M.]

That booth is in A1 condition, from Estes, CO. I got it after spending much of my career (but
not all of it), 41 years designing phone office equipment. Still looking for a rotary dial pay phone
at an affordable price. Bruce Roe

So I guess all this means we can assume you can engineer your way out of a phone booth by now, Right ?

[Kingram]

superman celebration.jpg He is out ..

[J.P.M.]

superman celebration.jpg He is out ..

"Superengineer !!"

Ya gotta' love it !

[bcroe]

It looks like a well engineered solution -- but I'm trying to wrap my head around
cost vs payback of changing tilt a few times a year.

And on the telecom career, Western Electric, Bell Labs, GTE Automatic Electric, or ???

There IS a Superman doll in the booth, not visible here. I worked at Bell Labs Naperville after they
opened it in 1966. We designed, then maintained and upgraded 4ESS, a massive project. It was
the first of the big electronic switches that changed everything, and the first AT&T switch to use
integrated circuits. It managed to serve for 4 decades, now it and I are retired.

Cost, did I forget to mention its a science project? If one doesn't like what exists, build something
better. After that, evaluate, decide which features are worth while, and figure how to reduce costs.
Sort of like at work.

My cost structure is different too. Saved big bucks digging my own foundation, not bringing in a
ready mix truck, free engineering, labor, wiring. Lots of what you see was on the property years
before this project started. A BIG POINT, its built on a considerable slope, no heavy earth moving
equipment used or retaining walls built, causing serious erosion problems later. It just follows the
slope, that saved a ton of time, labor, and money.

Its part of my dealing with clouds and snow in northern IL, should boost output under clouds some
20%, its already quite good. Bruce Roe

[J.P.M.]

There IS a Superman doll in the booth, not visible here. I worked at Bell Labs Naperville after they
opened it in 1966. We designed, then maintained and upgraded 4ESS, a massive project. It was
the first of the big electronic switches that changed everything, and the first AT&T switch to use
integrated circuits. It managed to serve for 4 decades, now it and I are retired.

Cost, did I forget to mention its a science project? If one doesn't like what exists, build something
better. After that, evaluate, decide which features are worth while, and figure how to reduce costs.
Sort of like at work.

My cost structure is different too. Saved big bucks digging my own foundation, not bringing in a
ready mix truck, free engineering, labor, wiring. Lots of what you see was on the property years
before this project started. A BIG POINT, its built on a considerable slope, no heavy earth moving
equipment used or retaining walls built, causing serious erosion problems later. It just follows the
slope, that saved a ton of time, labor, and money.

Its part of my dealing with clouds and snow in northern IL, should boost output under clouds some
20%, its already quite good. Bruce Roe

Looks good and like lots of fun, but I don't understand why it would boost cloudy sky system output by 20 %.

[bcroe]

Looks good and like lots of fun, but I don't understand why it would boost cloudy sky system output by 20 %.

Light clouds, I can still run close to 100%. Heavier clouds, might run 25% to 50%. Adding 20% panels here would
boost that to 30% to 60%. Bruce Roe

[DanS26]

Running 2 to 1 DC/AC ratio those Fronius inverters will be screaming on a sunny day.