Sun hours

[DanS26]

.......At 6:45 am sun time the newest
array (facing east) was well irradiated.........

Can the new array tilt to the west for afternoon summer production?

[bcroe]

Overnight we received some unwelcome ice followed by a couple inches of snow. But it did provide another
snow trial of the array, esp the latest design just put into service this month. At 6:45 am sun time the newest
array (facing east) was well irradiated, with no ice and barely any snow. One quick swipe and 6 KW were
operational. The next near vertical section wasn't entirely out of the shade yet, but took little effort to clear
the snow. What little ice was left, will soon be gone as the sun rises.

The less elevated section (facing south) had a solid layer of ice covered by a couple inches of snow. The
snow slots allowed efficient clearing of the snow, will have to wait for a somewhat more favorable sun
position (and the rising temp) to finish by melting the ice. But by 7am sun time, the system was producing
8KW, more than 50% of capacity. Sorry I didn't take a camera to record the event. Bruce Roe

[bcroe]

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

Part of the reason for easily adjusted tilt, is to better level out the power level over the day, an
ongoing experiment. The curves from a while back are some of the results. For the several
snow months, I expect to just put them vertical, possibly not the perfect angle but not a high
production time anyway. I expect them to them be nearly immune to snow, and ground snow
will do better with reflected sun. Bruce Roe

[DanS26]

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

[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

[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]

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.]

superman celebration.jpg He is out ..

"Superengineer !!"

Ya gotta' love it !

[Kingram]

superman celebration.jpg He is out ..

[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 ?

[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 ???

[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

[Mike90250]

One of the few remaining phone booths !

[SunEagle]

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

[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