December 2010 Power Production

December was generally -8 to -1 with about 10 cm snowfall mid-month. The second half of the month was almost always overcast. A thaw with rain melted all the snow on 27 Dec.
The panels were snow-covered most of the second half of the month and power generation was significantly reduced (see chart, Whr/day). The overcast days which were slightly below 0C did not provide sufficient radiant heat to warm the panels and melt all the snow off. This was clearly shown in the previous postings of the snow-covered panels. Partly sunny days just after Christmas resulted in some snow melt and snow sliding off about half of the panels (see earlier post with photos). This resulted in an increase in generation on 27 Dec.
The remaining days of December were very overcast with heavy dark cloud. Even the melt that occurred on 29 Dec was not sufficient to increase production even though the panels were clear. The increase on 31 December showed the benefit of clear panels and a little sunshine. Fortunately, the clear panels is helping increase generation during the first week of January which are a little more bright. Happy New Year!

Generation Results up to May 2012

The results of the power generated, in kWhr up to May 2012:

Sum - Daily kWhr	Years
Date	2010	2011	2012	Total Result
Jan		170	256	426
Feb		275	323	598
Mar		561	569	1130
Apr		493	626	1119
May		534	758	1292
Jun		707	13	720
Jul		769		769
Aug	164	658		822
Sep	438	528		966
Oct	450	391		841
Nov	355	316		672
Dec	78	220		298
Total Result	1486	5623	2544	9652

And the revenue, gross, generated up to May 2012:

Sum - Revenue, daily	Years
Date	2010	2011	2012	Total Result
Jan		$136.10	$205.18	$341.29
Feb		$220.57	$258.66	$479.22
Mar		$449.77	$456.57	$906.34
Apr		$395.30	$501.84	$897.14
May		$428.51	$607.72	$1,036.24
Jun		$567.19	$10.30	$577.50
Jul		$616.75		$616.75
Aug	$131.53	$528.09		$659.62
Sep	$351.28	$423.49		$774.77
Oct	$360.90	$313.65		$674.55
Nov	$285.03	$253.69		$538.72
Dec	$62.74	$176.31		$239.05
Total Result	$1,191.47	$4,509.43	$2,040.28	$7,741.18

Panel Shading Tools

Your solar provider should provide a very thorough analysis of your roof and near-by obstructions before you accept your contract. There are many websites that list tools and calculations. I found PVResources to be quite handy. [There is actually a lot of info on PVResources.]

There are some very handy tools to use, the primary one is the Solar Pathfinder. A solar installer would be able to provide a quantitative analysis of your roof and show you the areas that would be affected by shade.

Another interesting tool by Sustainable by Design that I found quite helpful was for tilted panels on flat roofs. I am sure you could use it on a sloped roof to estimate the impact of obstructions too. But I found it equally interesting to see the impact on our roof. See below! We don't have any obstructions from trees, etc. You can see with the white blocks our panels are fully illuminated, but after 4 or 5 pm the sun has gone far enough westward that it no longer strikes our SE facing panels.

Plotting Revenue Up To 14 May 2012

A quick chart to show the revenue generated from our system. The orange line is our daily loan payment amount. We don't pay daily of course, but I plot the line for illustrative purposes.

Figure 1. Daily revenue to 14 May 2012.

Here Comes the Sun!

A short blog update to provide you the latest data from my solar PV system. I have the data below for the first 2 weeks of May added to my monthly kWhr of generated power generation.

Sum - Daily kWhr	Years
Date	2010	2011	2012	Total Result
Jan		169.71	255.84	425.55
Feb		275.02	322.52	597.54
Mar		560.81	569.29	1130.10
Apr		492.89	625.74	1118.63
May		534.31	320.48	854.79
Jun		707.22		707.22
Jul		769.01		769.01
Aug	164.00	658.47		822.47
Sep	438.00	528.05		966.05
Oct	450.00	391.09		841.09
Nov	355.39	316.33		671.72
Dec	78.23	219.84		298.07
Total Result	1485.62	5622.73	2093.87	9202.21

I've mentioned in earlier posts that we need to generate approximately 375 kWhr per month to have the system pay for itself. As we've seen, December and January can be poor due to clouds and snow shading the panels. But March, April, and the first half of May have been good and more than cover the low generation from Dec-Feb. We are quite pleased that we are approaching 10,000 kWhr - likely by mid-June.

Ontario Power Authority 2 Year Review of Feed In Tariff Programme, Minister's Directive of 5 April 2012.

The Ontario Power Authority released the scheduled 2 year review of the FIT programme on 22 March. Yesterday they held a webinar to provide information to the public about the changes to the microFIT programme being proposed. There is a comment period and readers may see these details on the OPA website. The points below are the proposed changes to the programme, contract, and rules, take verbatim from the OPA website (I've put my comments in brackets):

Key changes to the FIT and microFIT Programmes include:

• As a first step, the FIT and microFIT program rules will provide for the awarding of 50 MW of microFIT and 200 MW of small FIT contracts as soon as possible. (applications in the queue will be processed and released soon)
• FIT applications will now be accepted only during an application window, rather than on an ongoing basis. (a more planned application approach -likely to help the OPA assess applications based on grid capacity and their ability to process the applications)
• Small project FIT applicants will now need to submit application security if they wish to apply or re-apply under the new program rules. (likely to reduce the number of speculative applications)
• Applications will be prioritized with points awarded based on applicant type, municipal support, Aboriginal support, project readiness and electricity system benefit. (allowing for greater community involvement in the development process)
• Solar rooftop projects must reach commercial operation within 18 months of receiving a contract, compared with three years previously. (if you get an application you need to build - this way the price you have to pay for the system reflects the price you'll receive for the electricity sales. Also, if you have grid capacity allocated to you then build now or give the capacity to someone else)
• Ground-mounted solar projects need to be located on lands that are not used for residential purposes and also cannot be adjacent to lands that are used for residential purposes. (proximity and land use decisions)
• Ground-mounted solar projects are permitted on commercial and industrial lands as long as it is the secondary use of the property. However, if the project is the only use of the property, it will be ineligible. (ground-mounted solar is the the main use of the land but ancillary. This will encourage more solar to be put on roof tops)
• In addition, ground-mounted solar projects can be located only on property that does not contain any Class 1, 2 or 3 soils, organic or specialty crop soils, regardless of zoning, or any mixed soils that contain Class 1, 2 or 3 soils. (protection of highly valuable lands)
• For projects other than rooftop solar that receive prioritization points related to the type of applicant, there are new restrictions on changes that would reduce the equity held by a community, Aboriginal group or health or education entity below the level that enabled the project to qualify for such prioritization points during the entire term. For rooftop solar projects that receive prioritization points related to the type of applicant, such restrictions apply from the contract date until five years after the commercial operation date. (ensuring significant community investment {and community benefit} and reducing the risk that "token" community investment will be used for the project only to be transferred to the main developer after project approval)

These points above are derived from the Minister's Directive released on 4 April 2012. This directive has many very important details and people should read this directive very carefully.

March 2012 Power Yield and How RETScreen is Doing

I've downloaded the data up to 13 April and I've put it in my spreadsheet to calculate the power yield for March 2012 (table below). It was marginally better than 2011. I am looking forward to the rest of April because so far the bright, cool days have been good energy producers. March 2012 was just 9 kWhr over last year. However, RETScreen calculations show that my system should have yielded 584 kW, so, two years in a row RETScreen is overestimating the system. Two years of data is not enough to say RETScreen is not accurate, but the overall trend with my system is underestimation. RETScreen calculated that my system should have produced 9128 kWhr to the end of March whereas my system did 8256 kWhr (10.6% under estimation). Most of the deviation came from the winter of 2010-2011 where snow substantially reduced the panel output. So, with this limited dataset, it points to people being conservative when estimating their payback expectations.

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	569.3	1130.1
Apr		492.9	313.5	806.4
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	1485.62	5622.72	1461.16	8569.52