May was a pretty rainy month in New England. Plus with all the pollen accumulating on my panels, I was forced into my first maintenance. In any case, I was not optimistic about my electrical production.
But it turned out to be a pretty good month nonetheless, with a $5.62 net metering credit appearing on my bill, my second consecutive month of producing more electricity than I’m using. Although I don’t think I’ll make it three in a row since I put in my window air conditioners last weekend.
So here’s my production summary thus far:
|Period Ending||Production||As % of Usage||Savings|
|Dec 21, 2011||223 kWh||32.5%||$45.05|
|Jan 24, 2012||288 kWh||34.5%||$59.26|
|Feb 23, 2012||419 kWh||72.2%||$86.81|
|Mar 23, 2012||484 kWh||87.7%||$106.48|
|Apr 24, 2012||663 kWh||110.4%||$145.86|
|May 21, 2012||536 kWh||105.0%||$117.92|
If there seems to be some inconsistency, it is due to monthly usage fluctuations, the number of days per billing period and NStar price changes. I also under-reported my Usage % last month because I forgot to subtract the $6.43 NStar flat fee before calculating it.
Note that my production dropped almost 20% from last month. That shows you how important sunny days are and why solar probably wouldn’t do so well in a place like Seattle.
Although that is a little deceiving since there were 5 fewer days in my NStar billing period this month than last. So, on a daily basis, my production dropped less than 4%. This is mainly because the sun is still rising in the sky and the days are still getting longer so on a day-by-day basis, I am producing more energy than I was a month ago. So while there were a lot more bad days, the good days were that much better.
Looking at my Enphase reporting, I can see that my top 6 energy producing days were all in this billing period, with the highest day being April 28th when I produced a full 33.0 kW. I assume that my biggest day of the year will be around June 21st or whenever the longest day of the year is, depending on the weather.