Sun hours

[bcroe]

As hoped, Feb production is heading way up. In other words, lots less clouds. A
week of good production topped by exceeding 100 KWH today. Bruce Roe

[bcroe]

How does it work in your area? Do they carry forward production
and then just zero out any net generation on some date?

They could at least send a Thank You card for the power you gave them.

They were very vague about that last year, net metering was a haphazard, by hand
operation. It was hard to tell what happened. But this year bills are regular again.

I believe they will reset 1 April or whenever they (manually) read the meter. The
plan was I get no credit for extra KWH, but A. I can burn extra heating the other
building, and B. It looks to be a very small amount anyway, which cost me nothing.
I can make 128 KWH in one sunny day. Or, I might run short, too close to call. Bruce

[pleppik]

2 more months till the Po Co
resets it to zero.

How does it work in your area? Do they carry forward production and then just zero out any net generation on some date?

They could at least send a Thank You card for the power you gave them.

[bcroe]

Just got the electric bill; here is the extended plot of KWH RESERVE this winter. The
slope right now looks like I'll zero out before 1 April. BUT I expect production to be
much better in a few weeks, than the just past months. And warmer temperatures in
March should greatly reduce usage, with the heat pump coming back on. So if we don't
have another terribly cold winter, I expect it is on track. Bruce Roe

Here is the 30 Jan version of my KWH reserve chart. 2 more months till the Po Co
resets it to zero. While the curve at 30 Jan doesn't look optimistic, the longer days along
with more sunny days, definitely improve the slope in Feb, more so in March. I have
taken last year's production, along with increasing March temperatures, and estimated
the curve to 1 April. It came out 128 KWH to spare. If this is correct, the annual energy
generate will match consumption by closer than 1%.

The next data point will be known only a couple of weeks before reset date; a decision
on how to finish will be made then. Bruce Roe

[bcroe]

PVOutput

I updated a year of output on PVOutput. Bruce Roe

http://www.pvoutput.org/list.jsp?p=5&id=30265&sid=29099&v=0&o=date&d=desc

[bcroe]

Here is a curve I plotted, of how much energy reserve (Po Co rollover) I had by date.

In June the heat was off, and the reserve began climbing
at a considerably faster rate than 2013 (more panels);

In Oct 2014 the reserve didn't flatten like 2013, but continued to rise on a lesser slope.
This is because the new heat pump was conserving a lot of KWH;

With the unseasonably cold weather, I had to shut down the heat pump in early Nov.
I am now on the reserve down slope. With 4 times the reserve of 2013,
it should last at least until the 1 April reserve reset date. Bruce Roe

Just got the electric bill; here is the extended plot of KWH RESERVE this winter. The
slope right now looks like I'll zero out before 1 April. BUT I expect production to be
much better in a few weeks, than the just past months. And warmer temperatures in
March should greatly reduce usage, with the heat pump coming back on. So if we don't
have another terribly cold winter, I expect it is on track. Bruce Roe

[SunEagle]

Something is in the sky!! Its... Its... the SUN! First time we in NW IL have seen it this
Dec. Depressing to hear the weatherman saying Dec has been 97% overcast. If it will
just stay for today, maybe the array will make more than 20 KWH. Good news is the
heat pump is doing well in this warmer weather. Even with it running, the meter says
I'm now banking most of the energy. Bruce Roe

It must be tough to have grey or cloudy sky's for weeks on end.

My wife was up in Lincoln Il. for a week in early December and never saw the sun. The good thing was there was no snow, just some sleet.

[bcroe]

Something is in the sky!! Its... Its... the SUN! First time we in NW IL have seen it this
Dec. Depressing to hear the weatherman saying Dec has been 97% overcast. If it will
just stay for today, maybe the array will make more than 20 KWH. Good news is the
heat pump is doing well in this warmer weather. Even with it running, the meter says
I'm now banking most of the energy. Bruce Roe

[SunEagle]

Here is a curve I plotted, of how much energy reserve (Po Co rollover) I had by date.
A few things of interest:
The system started up with south facing panels 1 Aug 13; reserve built up till cold weather
started 1 Oct. The east-west panels started working 1 Nov, but with shorter days and record
cold, reserve was gone in Jan;

The rest of winter 13/14 was run on energy being collected, a minimal amount of KWH
purchased, and some propane. I managed to conserve a single tank of propane into
the summer, to be refilled at the lowest price. The huge Feb propane price spike in Feb
was entirely avoided;

After reserve RESET in April, with longer days I managed to generate about as much
energy as was being used. In June the heat was off, and the reserve began climbing
at a considerably faster rate than 2013 (more panels);

In Oct the reserve didn't flatten like 2013, but continued to rise on a lesser slope. This
is because the new heat pump was conserving a lot of KWH;

With the unseasonably cold weather, I had to shut down the heat pump in early Nov.
I opened its circuit breaker, since it may have a compressor pre heater element (need
to check this). I am now on the reserve down slope. With 4 times the reserve of 2013,
it should last at least until the 1 April reserve reset date. The drop will be steeper,
because I'm not planning to use ANY propane for heat this year;

Come 1 April I'll have the struggle to collect as much energy as I use again. But if the
weather will allow a couple weeks use of the heat pump, it should be OK. In that case
the reserve built in 2015 should be even larger than 2014;

If I see a large surplus reserve in Feb/March 15, I'll burn some of it off with electric heat
in the car shop. It is normally kept around 40F except when working, with propane.

In another thread, someone showed a chart with (nearby) Chicago getting 3.14
SUN HOURS a day yearly average. That seems a little pessimistic, must be the clouds.
However, 90 mi west I managed 5.42 SUN HOURS for the yearly average, despite the
clouds & storms. Bruce Roe

Looking good Bruce. Hopefully you do not get a large number of snow storms or very low temps this winter.

[bcroe]

Reserve kwh

Here is a curve I plotted, of how much energy reserve (Po Co rollover) I had by date.
A few things of interest:
The system started up with south facing panels 1 Aug 13; reserve built up till cold weather
started 1 Oct. The east-west panels started working 1 Nov, but with shorter days and record
cold, reserve was gone in Jan;

The rest of winter 13/14 was run on energy being collected, a minimal amount of KWH
purchased, and some propane. I managed to conserve a single tank of propane into
the summer, to be refilled at the lowest price. The huge Feb propane price spike in Feb
was entirely avoided;

After reserve RESET in April, with longer days I managed to generate about as much
energy as was being used. In June the heat was off, and the reserve began climbing
at a considerably faster rate than 2013 (more panels);

In Oct the reserve didn't flatten like 2013, but continued to rise on a lesser slope. This
is because the new heat pump was conserving a lot of KWH;

With the unseasonably cold weather, I had to shut down the heat pump in early Nov.
I opened its circuit breaker, since it may have a compressor pre heater element (need
to check this). I am now on the reserve down slope. With 4 times the reserve of 2013,
it should last at least until the 1 April reserve reset date. The drop will be steeper,
because I'm not planning to use ANY propane for heat this year;

Come 1 April I'll have the struggle to collect as much energy as I use again. But if the
weather will allow a couple weeks use of the heat pump, it should be OK. In that case
the reserve built in 2015 should be even larger than 2014;

If I see a large surplus reserve in Feb/March 15, I'll burn some of it off with electric heat
in the car shop. It is normally kept around 40F except when working, with propane.

In another thread, someone showed a chart with (nearby) Chicago getting 3.14
SUN HOURS a day yearly average. That seems a little pessimistic, must be the clouds.
However, 90 mi west I managed 5.42 SUN HOURS for the yearly average, despite the
clouds & storms. Bruce Roe

[bcroe]

the Po Co didn't bother to send me a bill for SEPT.

I've been told the heat pump won't function for below freezing outside air.

In 2013 at this time, my total production since the net metering reset date was 5880
KWH. This year its 19,700 KWH, a lot better starting point for winter. I'll know how
much is in reserve if they ever send me another bill. Annual production is about
28,400 KWH. Bruce Roe

The heat pump is great, keeping me toasty well into Nov. while conserving KWH.
I can't see any blue sky, but with the pump running, net KWH reserve for winter is
still increasing. Finally got an electric bill (for Oct.}, reserve had reached 12,400
KWH. Bruce Roe

[bcroe]

Pretty awful sun day today, severe overcast with rain some of the time.
Managed 32 KWH.

Meantime yesterday was so cold here it set an all time record for 11 Sept. But a new
component is up & running. My old 1978 AC had died. One week ago a new 14.5
SEER heat pump went in, 3 ton air to air. Can't use it in the middle of winter, but today
it is heating the house while multiplying my KWHs. Will need them; another cold winter
predicted. Bruce Roe

The heat pump has been doing a nice job conserving my KWH reserve while keeping
the house toasty. The KWHs about break even for clouds, make more reserve when sunny.
Don't have precise numbers, since the Po Co didn't bother to send me a bill for SEPT.

Sunny today, making max KW. But the season has come where days may be well above
freezing, but the nights dip below. I've been told the heat pump won't function for below
freezing outside air. Not sure if the efficiency drops too low, or there would be icing up
of the outside coil. But I'd like to maximize its use until it gets really cold.

What I started doing is noting nights predicted well below freezing, then running the
house up to around 74F in the evening. About the time outside drops below freezing,
shut down & try to coast through the night. Soon as outside rises above freezing, bring
the heat pump back on to recover in the morning & build a little reserve in the evening.
So far it seems to be working.

In 2013 at this time, my total production since the net metering reset date was 5880
KWH. This year its 19,700 KWH, a lot better starting point for winter. I'll know how
much is in reserve if they ever send me another bill. Annual production is about
28,400 KWH.

Bruce Roe

[SunEagle]

That was the goal, get enough south facing panels for mild clipping at noon, then add enough
E-W to total nearly the same when the sun hits them. Probably wouldn't be so flat if there
wasn't mild clipping; lots of luck involved on this pass. I do have to wait for the sun to clear
the trees. But I can't increase the peak (without replacing EVERYTHING), so broadened it instead.

The prize for the picture won't push this project into the black; it WILL buy me another batch of
stainless steel bolts. Bruce Roe

Or a little more gas to run that plow to clear the snow off your array.

[bcroe]

We've had east-facing, south-facing, and west-facing arrays here for many moons to flatten our solar production curve during the day and maintain a relatively steady PV input to our power system. And we have a logging system that logs PV production once a minute. Our production shows a very rapid increase to a high PV output level early in the morning with the rising sun. But it certainly doesn't have a flat top like your curve. Our PV production still peaks at solar noon.

That was the goal, get enough south facing panels for mild clipping at noon, then add enough
E-W to total nearly the same when the sun hits them. Probably wouldn't be so flat if there
wasn't mild clipping; lots of luck involved on this pass. I do have to wait for the sun to clear
the trees. But I can't increase the peak (without replacing EVERYTHING), so broadened it instead.

The prize for the picture won't push this project into the black; it WILL buy me another batch of
stainless steel bolts. Bruce Roe

[ChrisOlson]

Decided to graph the level of my AC energy output over a sunny + cool day.

We've had east-facing, south-facing, and west-facing arrays here for many moons to flatten our solar production curve during the day and maintain a relatively steady PV input to our power system. And we have a logging system that logs PV production once a minute. Our production shows a very rapid increase to a high PV output level early in the morning with the rising sun. But it certainly doesn't have a flat top like your curve. Our PV production still peaks at solar noon.