


Code: Select all
2017 2016
Jan 787.68 846.75
Feb 827.43 1,260.48
Mar 1,420.07 1,364.66
Apr 1,569.70 1,421.10
May 1,343.54 1,234.13
Jun 1,473.96 1,486.90
Jul 1,516.38 1,620.35
Aug 1,340.45 1,476.57
Sep 1,156.03 1,234.49
Oct 1,129.70 1,111.95
Nov 787.77 992.07
Dec 324.97 749.82
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Energy Table
2012 6,132.38
2013 15,442.73
2014 15,280.89
2015 14,966.99
2016 14,799.27
2017 13,675.74
Wow! You've lost about 9% of your production in four years. (I used 14.1 MWh for this year.) That's better than a Nissan LEAF battery, but not a whole lot better.davewill wrote:Plus the system has been showing a steady year by year decline, then a steeper one this year (we aren't going to make enough between now and the end of the year to make this look tons better.Code: Select all
Energy Table
2012 6,132.38
2013 15,442.73
2014 15,280.89
2015 14,966.99
2016 14,799.27
2017 13,675.74
I'm on a lease, so I called Sunpower. They agreed there is something up and will be sending out a technician. Should all be on their dime.
davewill wrote:Well, I hadn't checked on my production for a while, so I did. Low and behold, the much of the last year is showing a significant decline, especially Nov, and Dec isn't looking any better despite unseasonably warm and sunny weather in SoCal this fall. Just as telling the peak numbers are lower, too.Code: Select all
2017 2016
Jan 787.68 846.75
Feb 827.43 1,260.48
Mar 1,420.07 1,364.66
Apr 1,569.70 1,421.10
May 1,343.54 1,234.13
Jun 1,473.96 1,486.90
Jul 1,516.38 1,620.35
Aug 1,340.45 1,476.57
Sep 1,156.03 1,234.49
Oct 1,129.70 1,111.95
Nov 787.77 992.07
Dec 324.97 749.82
Plus the system has been showing a steady year by year decline, then a steeper one this year (we aren't going to make enough between now and the end of the year to make this look tons better.Code: Select all
Energy Table
2012 6,132.38
2013 15,442.73
2014 15,280.89
2015 14,966.99
2016 14,799.27
2017 13,675.74
I'm on a lease, so I called Sunpower. They agreed there is something up and will be sending out a technician. Should all be on their dime.
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Old panels New panels
2009 1165 kWh
2010 1132
2011 1203
2012 1227
2013 1179 2148
2014 1145 2072
2015 1125 2034
2016 1150 2077
2017 1109 1988 (as of Dec 11)
dgpcolorado wrote:One thing that I do see very clearly from day-to-day is that I get better production in colder temperatures, other things being equal. Is it possible that generally warmer weather this year, and in recent years, is causing a drop in production?
Nope, with a temperature coefficient of power of -0.3%/K, the average temperature of San Diego, CA, would have had to have risen by over 54 degrees Fahrenheit to account for a 9.1% drop in production. In fact, there was no real change in temperatures between 2013 and 2017:dgpcolorado wrote:Is it possible that generally warmer weather this year, and in recent years, is causing a drop in production?
NeilBlanchard wrote:Are trees growing taller, and shading your system more over time?
Sure enough, January 30 saw a new momentary production peak, so I thought this would be a good time to update our system's production through January.RegGuheert on December 8, 2017 wrote:Due to the pointing angle of the M250s on the roof, I don't expect to see the full 12.775 kW at any time this winter, but I do think we might see over 12.5 kW, particularly on a cold, clear day when there is snow on the ground (and none on the arrays).
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Month PVW42 2011 2012 2013 2014 2015 2016 2017 2018 PVW54 Units
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January 916 669 869 822 857 1006 1300 756 1300 1229 kWh
February 702 158 1085 866 1054 1361 1192 1241 915 kWh
March 965 0 1350 1152 1113 1547 1498 1572 1240 kWh
April 1465 0 1465 1495 1338 1737 1754 1654 1899 kWh
May 1583 0 1477 1491 1457 2069 1574 1618 2074 kWh
June 1268 0 1478 1368 1521 1585 1932 1916 1666 kWh
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July 1448 595 1395 1406 1880 1823 1887 1792 1902 kWh
August 1442 1347 1447 1333 1794 1887 1932 1778 1875 kWh
September 1209 910 1295 1414 1577 1495 1551 1612 1555 kWh
October 1304 931 981 1034 1258 1415 1593 1587 1713 kWh
November 864 949 1041 1018 1227 1277 1340 1205 1154 kWh
December 820 803 612 669 812 865 1002 985 1108 kWh
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Totals 13986 6362 14495 14068 15888 18067 18555 17716 1300 18330 kWh Total: 106.451 MWh