Little Snow Means Better Solar Production in 2011-2012

Spring is already here but our 2011-2012 winter ended a long time ago. There has been very little snow - I didn't have to shovel much since Christmas. The sky seems to have been clearer too and this has enabled our solar array to generate more power than last winter. It means a lot too, financially. Last August was our 1 year anniversary and on a $30k investment after 10-year loan payments, we netted $460 - not a great return on investment so hopefully 2012 will be better. So far, so good. Here is our kWhr generated by month in Table 1.

Sum - Daily kWhr	Years
Date	2010	2011	2012	Total Result
Jan		169.7	255.8	425.5
Feb		275.0	322.5	597.5
Mar		560.8		560.8
Apr		492.9		492.9
May		534.3		534.3
Jun		707.2		707.2
Jul		769.0		769.0
Aug	164.0	658.5		822.5
Sep	438.0	528.0		966.0
Oct	450.0	391.1		841.1
Nov	355.4	316.3		671.7
Dec	78.2	219.8		298.1
Total Result	1485.6	5622.7	578.4	7686.7

If I use Dec-Feb to define winter, then we yielded 523 kW in 2010-2011 and this year 798 kW. That is a 275 kW difference or $220.55 difference in revenue. We'll see what this March brings to be able to compare two full winters. December 2010 and 2011 were especially different because Dec '10 was dark, dreery, and frequent intermittent snow that accumulated on the panels and seldom fully melted off or slid off.
The system didn't get connected until 25 August, so ignoring that we can see that most months are better than the year before, other than Oct and Nov 2011. We had a "dark" fall, but otherwise, I see it is all going well.
As you may read in this blog, I focus on the numbers, kW, dollars, and cents of our solar system. I am interested in these results today as it shows that you can't use a single year to determine if production data. Or any coefficients either. In an earlier posting I calculated the typical coefficients people use to estimate the power generation for our first year. I look forward to calculating this year's coefficients, plus to calculate the values for the duration of the system - that way we'll get the general values to expect for a multi-year estimation of coefficients.
So far, so good.
Oh, a little note about how I analyse these data. I use OpenOffice Calc to store and analyse the data. I use the Data Pilot tool [Pivot Tables in Excel] to summarize the data very quickly and easily.