23 October 2013

Solar Costs in Germany and USA

I found this interesting article that analyses the differences in costs of solar PV systems in Germany versus USA. I don't have a similar analysis of Ontario costs, but I am looking - let me know if you have seen any research on Ontario solar PV costs.
http://cleantechnica.com/2013/02/17/why-german-solar-is-so-much-cheaper-than-u-s-solar-updated-study/

08 October 2013

Solar Generation Results to Sept 2013

I am updating the results of the solar PV system, below. It is now 3 years and a month since the system was installed [well, and a little bit of October too and the few days in August 2010]. This is giving me a good range to see what good and bad months are, as well as how the system is faring relative to what i hope was to be the rate of return.
First, I have my set of important variables : mean daily total kilowatts, mean kilowatts per watt installed, minimum and maximum output days. And the same is in dollars, as calculated from my data. However, what my datalogger calculates as output and revenue is less than what my Guelph Hydro meter shows. This is what I hear from others - what their system reports seems to be less than their utility's meter.  I haven't heard of anyone producing more than what their meter is reporting.

Variables kW Dollars


Mean 15.96 $12.80


Per 1 kW 3.26 $2.61


Min 0.05 $0.04


Max 35.44 $28.42














Sum - Daily kWhr Years



Date 2010 2011 2012 2013 Total Result
Jan
169.7 255.8 242.6 668.2
Feb
275.0 322.5 213.8 811.3
Mar
560.8 569.3 499.5 1629.6
Apr
492.9 625.7 573.5 1692.2
May
534.3 757.8 767.9 2060.0
Jun
707.2 714.6 632.6 2054.4
Jul
769.0 762.4 693.0 2224.5
Aug 164.0 658.5 719.7 725.9 2268.1
Sep 438.0 528.0 599.6 572.8 2138.4
Oct 450.0 391.1 337.5 87.8 1266.4
Nov 355.4 316.3 286.3
958.0
Dec 78.2 219.8 144.3
442.4
Total Result 1485.6 5622.7 6095.6 5009.5 18213.4
as of: 2013-10-08




And you are likely asking, well, just how variable is it by month? Are the summer months consistently bright and the winter consistently dull? I know, you wanted to know the coefficient of variation, and now that i have 3 months (4 Septembers), i have done the calculations for you:
MonthCV
Jan0.21
Feb0.20
Mar0.07
Apr0.12
May0.19
Jun0.07
Jul0.06
Aug0.05
Sep0.13
Oct0.14
Nov0.07
Dec0.48
What it shows, for this limited dataset is that June, July, and August are fairly consistent between the years, with only 5 to 7% variation, whereas Jan, Feb, and esp Dec are quite variable between the years.