Introduction
When we moved to our new home in Lakeshore, Ontario, (near Windsor) in Southern Ontario in August 2012. I looked at putting solar energy harvesting equipment (AKA solar panels) on our roof. I based my analysis on 12 cents per Watt and not on the higher 54.9 cent rate. When I found out that the Ontario microFit tariff or contract rate was much higher, I started to investigate the feasibility of a Solar Panel Roof mounted system or program for our home. As an engineer, I used the internet to quickly accumulate a vast amount of information on design, local solar radiance, equipment types, solar panel specifications, component analysis, failure rates, etc.
Caution:
You must be approved for your electrical feed line and gain approval with an offer to connect from the microFit Power Authority BEFORE you spend any money.
Maximum microFit Size is 10 kW DC.
Your 10 kW AC Inverters will automatically limit you so I don't understand why they have the DC limit if they want to protect the environment.
Maximum microFit Size is 10 kW DC.
Your 10 kW AC Inverters will automatically limit you so I don't understand why they have the DC limit if they want to protect the environment.
Educate yourself about Solar before signing anything. This is a good place to start and maybe all that you need. Help us and others to reach the safe CO2 levels of 350 ppm. Every little thing helps. Harvesting energy to meet your electrical consumption is a good first step. We expect to harvest more energy than we use, at least on good days. We currently are at 395 ppm on this planet.
The Conservatives have stated that they will stop this microFit Program and keep funding big business paying in some cases for them NOT to produce energy. That tells me that it most likely is a good idea for the average home owner.
Installing Solar panels in our case will mean never again having to pay for our electrical consumption even after the 20 year microFit contract. After the contract, we remain grid tied and they will pay us the current electrical consumption rate. Current forecasts is for a 40% increase in your electrical bill over the next 3 years.
We found out that Flexible Solar in Windsor, Ontario are one of the best microfit solar panel installers serving Southern Ontario.
Again, for example; Mike Holmes says that we need good structure for our houses and solar panel systems also need a good structure (railing system) plus a well built Tier one solar panel. Be careful not to buy cheap products. We used Schletter Rails which is the best Rail System that we know of.
Your key result areas are:
Reliability, long life, maintainability, optimization, maximum ROI, Tier 1 Manufacturing, Safety
Beware of these type of DC to AC Inverter Systems:
A horrible labor cost to maintain.
3.String Inverter Systems that do not turn off power to panels when switched off. Most systems will maintain 600 V at each panel when turned off. Not good for Firemen and when changing out panels. SolarEdge reduces voltage at panels to 1 V when turned off.
You will lose $20,000 over the life of the project.
Current MicroFit Program - 39.6 cents per KW - Maximum 10 kW DC side.
Current rate is lower but still such a contract can net you $6-7k+ per year added income which is taxable IF you get the right people to work with you to optimize the program for your particular house.
Why settle for $5k per year ($100,000 gross) when you can get an additional $20-40,000 (up to $140,000) over the 20 year project life.
You Don't Need to have any Money?
NOTE: If the Conservatives get into power they want to stop this green energy program.
Our System
UPDATED JUNE 2014:
Our 22.5 degree pitch garage roof was in fact a bit of a blessing. The lower pitch angle allows the sun to hit the east panels up until 5:30 pm or 3 hours after solar noon. That is a real good thing making our harvesting curve much fatter. The array results: The east/west array produces or harvests 25% more than south facing panels from April to Sept or 45% more than static east facing panels. Putting the panels into any type of cooling wind also helps it to produce more power.
System Optimization - Maximize Your ROI and Gross Income
Understanding Solar:
Because the Earth is tilted on it's axis, we get seasons as we orbit around the sun. We are actually closer to the sun in the winter than the summer. On Jan 3 the solar radiance is 7% higher than on 3 July. The sun moves across the sky in what is called a "great circle". The Earth's rotation stays the same so movement in time from solar noon is about the same all year round. Solar noon in Windsor during daylight savings time is 1:34 PM. That is one hour for DLST and 34 min for time zones. The tropic of cancer occurs at 23 degrees 26 min north of the Equator and reverses in winter. For summer with a 22.5 degree roof, your panels should be latitude minus the sun's latitude or 42 -23.5 or 18.5 degrees. We have a 22.5 degree roof. That means on the 21 June the sun is about 4 degrees past optimum. That is good. It means that we will get more intense sunlight as it moves during the summer months on our panels. With the longer summer days, the sun rises at around 6:10 AM and sets around 9:10 PM.
Compare that to the winter months in December sun rises 9 AM and sets 6 PM on daylight time for comparison. With standard time that equates to rise at 8 AM and sets at 5 PM in December with a real time effective sun at 9 AM and setting at 4 PM. So summer gives us up to 7 hours more sunlight to harvest or almost double the Winter hours. Because the angle in winter is so bad, we don't get a good concentrated sunlight on our panels and we get less sunlight all amounts to much less harvesting.
You will find on the internet that the best orientation of your panels is considered to be on the angle equal to the latitude for a yearly average. Here in Windsor that is around 42 degrees (see Feedback note below: most likely 30-34 degrees or around a 7:12 pitch). That will look terrible on a 22.5 degree roof (5/12 pitch) so mount on the same angle as your roof or in my case you would NOT have a happy wife. Don't worry too much about your roof pitch as there is little that we can do about it.
What is the effect of Not having the Perfect Angle of Attack?
If the Perfect Angle for Winter is 65 Degrees (42 + 23.5) you would get 100% solar input for your Panel
If that angle is reduced to 60 Degrees, then you would get 99.6% or the cosine of 5 degrees
In Winter, my 22.5 Degree roof is off by 43 or 73 % of maximum
with about 7 hours of usable sunlight (took away 2 hours)
For March 21 the sun is over head at the equator so you have 42 -22.5 or 19.5 degrees = 94.3%
with 10.5 hours of usable sunlight
For June 21 you have 42-23.5=18.5 -22.5= -4 or 99.7 %
with about 13 hours of usable sunlight
*I took away two hours from sun rise to sun set until we get good light on our roof.
Spring and summer hours might be 1/2 hour more sunlight.
You got to love the Spring, Fall & Summer for Solar Panels.
NOTE: I had some good feedback on what is the best angle for fixed roof mounted solar panels. On December 21 the best angle is 65.5 Degrees: On 21 March that becomes 42 Degrees: On 21 June that become 18.5 Degrees. I did not go further on this as I have a fixed 22.5 Degree roof and anything else is a Moot point. It did occur to me and others that the ideal is most likely less than 42 Degrees because of the longer days. One reader believes 30 Degrees is the optimum value. I can not disagree with this nor agree 100%. I would like to have that 7:12 pitch roof but I don't.
I do however have some real world inputs. Another location has 20% more DC installed than we do (they have a higher tariff rate and are permitted to have more DC generation). The angle of their roof is around the 42 Degree mark. On the 24 December they had a peak output of 9 kW (outstanding as you will be limited to 10 kW from your inverters). Ours was 7 kW with one south panel not producing maximum and 8 panels on east and west total. They have mono and we have poly panels. Mono can produce a bit better in the cold and poly in the hot days. If we had 20% more DC then we would have produced around 8.4 kW peak output. Now account for the poor angle that we have and we did excellent. It is also reported to me that that person does very well in the summer as expected. Remember, the sun rises SE at this time of year and NOT due east. That makes south facing panels extremely desirable from October to March. South facing panels do well all year round. When we have the optimum solar angle of 22.5 Degrees that person will still be at 42 Degrees. Our East and West panels produced double of normally statically mounted panels, but still only about 75% of the south panels in December. They are optimized for the period from March to October when we have longer days and the sun rises and sets a lot more from the east and west. I expect to slightly out produce this person in May and June because of our roof angle is better suited for the spring and summer and fall.
I wanted some East and West facing panels to widen my histogram or in plain terms harvest the solar energy as early as possible in the morning and as late as possible during the evening.
I STRONGLY DO NOT RECOMMEND NORTH FACING PANELS
You may be laughing. Some one put them on a house in Windsor.
Again, some horrible people in this business.
Again, some horrible people in this business.
Even with 6 panels being shaded by two tree trunks and 3 panels being shaded by the garage roof until noon, we produced just under 40 kW for the day. One tree is now 9 feet lower and the other will also be lowered shortly (removal is a Work in progress). I expect that all shading issues will vanish as the sun rises higher in the sky in January through March as we gain on average 7 degrees per month. We started to produce 2 kW at 9 am and 5 kW just after 10 am and peak around noon. The curve is below. All in all, the 24th of December was a great solar day with only intermittent clouds. The wind gusts required that I lower the West panels earlier than I wanted to. Just after noon time, I happened to notice that a solar tracking array had to lay flat because of the wind. I was able to keep the East panels up as the wind was from the NW and our main house roof sheltered the panels from the wind. The panels automatically lowered after 5 PM when we were gone.
UPDATE: Both Tree trunks now lowered to prevent shading.- 26 December 2013- May 2014 both tree trunks are now making great garden supports for our veggies: ie they both have been cut down.
Any shading will significantly reduce the panel's output. See below.
Solar Edge Optimizers Saves the Day:
NOTE_2: Seeing is believing. I had to strain my eyes to see the very faint shadow cast from these two remaining tree trunks located some 35+ feet from the roof. The reduced panel output was horrible. The optimizers prevented the entire string from producing 50% less. You could see the progression of decreased output as the shadow moved across that part of the roof in the morning finally ending just before noon.
In Winter, the sun rises from the South-East and sets South West. That means both East and South panels see the sun as it rises.
In the summer as the sun rises from the East, our South facing roof has a delay before the sun hit the panels. At that time of the year, the East and West have a big advantage. The angle of attack is very good, the duration of solar harvesting is great. Temperature is your biggest nemesis.
The Sun Does NOT reduce its energy output in the Winter.
The 5 kW value was reached at around 10:15 AM. The data is gathered every 15 min. The drop to 4 kW was not for more than 5 min and should be ignored. The above histogram is great. Power rapidly rises from 9 AM to noon and maintains good output until 4 PM. This is mainly because of our south facing panels and the fact that the sun rises in the South of East and sets in the South of West. The East and West panels did very well because they were moved throughout the day. They produced 75% of the value of a south panel. Normally that would be about 33% of South if the panels were not moved.
To summarize:
Temperature Effects:
Panel Selection:
Poly-crystalline panels are better in hotter climates than monocrystalline. Panel type selection is not a simple thing. Poly also does have some small advantages in low light conditions (1-3%) and angled light sources. Mono panels can also produce the largest output up to 310 W for 60 cell units. Manufactures advertise that their poly panels have the best - 96% low light radiance and indirect light performance.
The best panels out there are the SunPower mono panels.
FORGET about using them in Canada.
You can't get them, and they are not CSA approved.
They must be installed by a registered SunPower installer in the USA.
We used a Tier One panel manufacture and selected a panel that gives us more output than regular panels with a Tedlar backing.
DC to AC Inverters:
A 350 V DC system is much better than a 240 V AC system. That reduces your transmission line loses.
Micro Inverters look like a good alternative but they are not IMHO. Add in the expected early failure rate (IMHO), extremely poor maintainability (they are located under the panels on the roof), and the 240 V lines, plus the huge cost for all of the parts required to put them together. Micro Inverters do include a system monitoring program.
I recommend that you AVOID, AVOID, straight string inverters and micro inverter systems.
Click to see a comparison ow SolarEdge verse microinverter systems
What are Optimizers?
Optimizers are used only on string inverter systems. They look at the panel output from their panel (you need one per panel) and add it to the string output without lowering the output from the string. Thus eliminating a major flaw when using string inverters. They also "talk" to the inverter. They are a MUST HAVE component of any solar panel system that uses string inverters. They also give a panel monitoring system.
How do Optimizers Work?
This is my best guess only. Every solar panel output power at around 37 Volts and for 250 W the amps will be 6.75 A. The bus or line voltage is maintained at around 350 V in a SolarEdge system and not the normal 600 V that others use. Power is the product of Voltage times Amps. If you electronically increase the voltage from the panel to this 350 V value, then the amps must decrease accordingly. For a 250 W input the amps will be 250/350 = 0.71 A Now add a second panel and you will double the amps. If the panel is producing half power, then half the amps will be added. With no power it is like a short and like the panel is not in the circuit. Now knowing the power from every panel in every optimizer, you can monitor your complete system.
Remember, Optimizer DO NOT produce AC power, or any DC power and NO inversion of the power occurs at the optimizer. Thus NO APPRECIABLE HEAT is produce in the units. DC power is one continuous straight line pulse. AC power is a sine wave. Capacitors are needed to convert the DC to AC power when connecting to the Electrical Power Grid -AC. The best ones to use are electrolytic caps but the down side is that they have a shorter life. Big Inverters like Solar Edge can use larger capacitors which have a longer life span. The String Inverter companies have operating history and know that their caps will not last much over 12 years or so. That is one of the reasons IMHO that smaller micro inverters will also experience similar failure rates. Do NOT confuse mean time to failure with life expectancy. MTTF is totally NOT applicable here. They will try to BS you as they did me. It is also why a it is a good reason in this case to buy the extended warranty from SolarEdge for about $400 per inverter.
When I taught my students programming, database and computer repair I would tell them to watch for these two rules:
1. Common sense is not so common.
2. Good advice is seldom followed.
When something went wrong, I would ask the adult class, well which one was it? It always brought a good laugh.
Your can achieve all of the benefits of a Micro Inverter System with elimination of most of the problems by using a String Inverter System with Optimizers. Although not really known, they must add at least 10% to your system income alone (some say 24%). Sometimes a lot more. They also give you a monitoring system so you can see if a single panel get fouled or is not working properly. The main draw back is cost but lower than a micro inverter system. They do not however generate heat and the capacitors used have a much longer life (ceramic capacitors) making claims of 25+ year life seem realistic.
Most Micro Inverters use Electrolytic Capacitors (with 8000 hour life capacitors NOT the 100,000 hour life needed here) which have a much shorter life span. So string inverters with optimizers is your first optimization step. It add a huge flexibility in panel orientation and design.
You can't mix east, west, south panels with normal string systems.
You can with a String System that has optimizers like SolarEdge.
The SolarEdge engineers are smart enough to give you 300 W (60 cell), 350 W (72 cell) , 400 W (96) and 600 W options not like others who started at 190 W and then 215 W maximum power output. Considering panels today can produce 250 W, 310 W and 400 W + what are they thinking? Why limit your system output in you inverter if you don't have to? The SolarEdge optimizer selection is also based on the number of cells in the panel, so make sure you get the correct optimizer.
UPDATE APRIL 2014: Go with the new 400 W optimizers
Place your SolarEdge Inverters in a protected area that is easily accessible for future replacement of the Electrolytic Capacitors. Buy the twenty year warranty for around $400 per inverter. Beware of over charges.
A Closer Look:
Let's look at that a bit closer. Let's say our 10 kW install will bring in $5500+ gross per year (SolarEdge) It will gross $110,000 over twenty years. At the end of that period you tie to the Power Grid and still make money but pay no electric bill. A straight string inverter system with out optimizers would bring in a lot less money($10,000+ less). In fact our system just will not work with that type of system as we load balance each inverter with the east, west and south facing panels.
We are very fortunate to have a large truss roof that faces north and south. Our roof pitch is 5/12, where a 7/12 would be much better. We have what we have and that is it. Our garage is also a blessing as it faces east and west. After orientation, temperature is you next nemesis. East panels out produce west panels in the summer, simply because they are cooler in the morning. The heat coming off of your roof will reduce the output. Poly-crystalline panels are better in hotter climates than mono. But panel type is not a simple selection. Poly also does have some small advantages in low light conditions (possible 1-3%). The best panels out there are the SunPower mono panels. But, forget about using them in Canada. You can't get them, and they are not CSA approved. Some mono panels also have much higher efficient silica giving you more power for a limited area. This is changing yearly.
Now optimize the system a bit more and increase your harvesting by +10%. That equates to $121,000 over twenty year. Your ROI just rose $11000 with a small increase in your capital investment (about $1200). This was achieved though proper panel selection. We used a Tier One manufactured panel that simply out produces all other panels. In this case what you see is what you get.
A word on panel selection. There is a test facility in Kortright that some manufactures use the results to show that they have the best panels. This should be a good thing but it is open to abuse or manipulation by smart marketing managers. The purpose of this site was to demonstrate that ALL Tier 1 Manufacturers produce good quality panels which they do. An error was made during the flashing of the 72 cell panel. The flashing equipment was not calibrated for 72 cell panels. You will see that most mono panels produce the same amount of power. Their is no real difference here. What has happened, is that some manufactures have increased their prices based on this site, claiming to be the best. A closer analysis would show something different. Panels lose up to 3% of their output after 1-7 days of burn in. A smart marketing manager would select their best panels, burn them in and then rate them and then send them in for testing. Rating panels for Ontario is a whole other discussion that I will not go into at this moment. Mono offers higher outputs at times and may be the best choice if you don't have enough roof area. That is the case of my garage array and mono would be a good choice for it. Mono panels at the time had a cost factor exceeding 40% over our poly panels with very, very little improvement in output. It all comes down to ROI and cost per Watt. I hate to pay more money per Watt than I need too. Panel efficiency keeps improving so we may see some good things in the near future. Most of these panels produce the same output. All are good. There is only one panel with a 72 cell configuration. Apparently, it was not properly flash tested with a 72 cell standard and a 60 cell standard calibration unit was used. Again, these panels are still high quality equaling all of the other manufacturer's in Ontario. Heliene Canada also make the highest efficient cells and the largest panels available at 440 W. When people use high quality silica like this, they normally don't cut back on other parts of their panel design. They also have an amazing 335 W 72 cell with 17.7% panel efficiency. The biggest problem we currently are facing is low efficiency solar panels at or below 15.% or so. I love the approach that Heliene ans Silfab are taking with their 17.7% efficient panels. Using their 72 cell 335 W panels mean fewer optimizers to buy and more room for more panels.
I am waiting for the day that 20%+ efficient panels are available. That means a 60 cell panel will give us around 300 W. and not your typical 225-240 W. I understand that they are working on a 40% efficient solar cell. Cost will be a factor. We don't have the $300,000,000. spent of the solar panels for the Space Station.
IMHO every 60 cell or 72 or 96 cell manufacturer with a Tier 1 facility like:
Heliene Photovoltaic Modules
Eclipsall Energy Corp.
OSM Solar Corp.
Silfab Ontario
Solgate
and others should all produce good quality panels. With cut backs in pricing, you do have to watch that all of the panels components will last your 25-50 years. Speak with the guys from Flexible Solar , they will tell you what you should buy. We shouldn't have to pay more for the illusion that you may see on this site. Pay attention to the panel's efficiency, construction materials and performance. A lot of manufacturers use the same silica waffers. Some use better quality silica and that is we we should focus on as long as the panel is build to a high standard. Beware of none Tier One manufactures. Tier One is fully automated with clean rooms and a robot to do the work. All panels need people to attach the box at the back of the panel. Some may have difference in design that you may like. To me, it breaks down to ROI. Other factors like minimum roof area will benefit from higher efficiency panels. There is always a variation from one panel to the next. Some people separate the better panels out and charge you more for them. Some don't do this.
UPDATE April 2014: We installed 5 Heliene 72 cell panels with excellent results. After a 2 week burn in the panels are producing 23 % more than similar 60 cell panels. So the test facility results are lower than we are seeing. We are very, very happy with these polycrystalline panels. Again, most panels are similar. I choose poly for the best ROI and low light performance.
A word on Panel Backing Materials
In this era of cutting corners, make sure that the panels all use good quality frames and backing. We recommend using Tedlar backing most likely in a T-PET-T sandwich. Tedlar is proven to last 25+ years. The purpose of the backing and encapsulation is to hold every thing together and seal if from any moisture or oxygen penetration that will corrode the junctions. Historically Tedlar (PVF) from Dupont was the standard backing material. It is very pricey and some people are using alternatives. One of these is Kynar (PVDF) which apparently has been used in Germany for over 25 years. It appears to be a good replacement for Tedlar. Another solution is to use a Tedlar-PET-Tedlar sandwich which is also good. Straight PET was found to be cracking in Spain after 4 years (see references below). It has become the old "buyer beware".
Exposure or Daily Harvesting Optimization
I recommend that you install the maximum amount of panels that you can. More panels normally have a lower cost as you have to over come the fixed system installation costs. Now take 20+% of you harvesting equipment and make it work from sunrise to sunset if you can.
South Facing panels will work better in year round simply because the location of the sun. they even turn on earlier from October to March because the sun rises from the South East and not due east.
East and West will have more time of exposure provided there isn't any clouds in the summer.
Clouds are a huge penalty in late fall and in Winter. January is normally much sunnier than December.
In the Winter months we get about 8 hours of total sunlight, 7 good hours after we clear the neighbors houses. Our 80% South facing panels will produce for much of this 7 hours. It is fun to watch how much more the ridge line panels harvest due to longer exposure times. All this time the sun is low on the horizon so the concentration of sunlight is much less than in the summer. There are no racking systems that you can adjust seasonally to make harvesting more efficient. Besides, most people would forget to adjust them anyway. At the same time our east/west panels are lying flat they harvest about 1/3 as much energy as the south panels. So by automating the movement of your east and west facing panels though out the day, you increase the direct exposure on the panels by at least 2 times in winter and possibly over 3 time in the summer compared to south facing panels. Testing in the winter has shown east/ west panel output to be about 75% of south with our positioning array. This will improve after 21 December as we get closer to March 21.
That means that our 2 kW panels will act like 4kW (winter) (Proven) and most likely 6kW (summer not proven yet) of installed panels as compared to your fixed south facing panels. We are limited by the peak of 10 kW at the inverter. We want to widen the harvesting time as much as possible. That means more East/West harvesting.
We want to optimize the system for Summer when the days are longer and the sunlight is more concentrated.
South facing panels have long been thought to be the best orientation. Here we are just being a bit creative. We are limited to installing 10 kW DC unlike the original people who could install any amount on the DC and they also got 85 cents per watt.
Remember, your inverters are limited to 10 kW. So why the DC limit then if you are a 10 kW microFit system? With so few people installing solar panels and the need to lower our CO2 levels is so great there should be no limitations other than the 10 kW which would be better at 20 kW DC.
When I worked in Ontario Hydro's Nuclear operations as an Engineer, all we heard was Solar and Wind energy should be used. Now, people complain about Wind Turbines and Solar Panels, go figure. We always thought that there was nothing wrong with a little "Nukie" (humor). This was long before CO2 levels were considered to be an issue. We can produce more energy than we use. Solar and Wind Energy harvesting does not produce any of the harmful by products of conventional electrical generation.
Cost of panels has significantly decreased from over $800 for some to around $200 per panel. Greed by the utility, local governments and ridiculous regulations in some cases significantly increase the cost of the system. Your inverter costs have also significantly been reduced. We have a manual shutdown switch for the arrays on windy days and are playing with adding an automatic wind speed shutdown switch plugged into the PLC.
Optimization of the 8 East and West Solar Panels
That is 3 peaks per panel every day verse one and all day harvesting.
I could design the system to give me 3 more peaks per day but that makes things a bit more complicated. I will how ever look at the benefits of doing that later. It means a lot more control equipment.
Another factor to consider is that the sun rises and sets at different times of the year and changes on a daily basis. I programmed the PLC to correct for this on a monthly basis. I could have programmed it on a daily basis but deemed it not worth the trouble.
So in summary, our $6000 income can be increased by a minimum of $1000 per year conservatively by moving the panels though out the day in order to maximize the solar harvesting. The ROI of the added cost is around 7:1 in our favor. That should upset the utility who openly hate this green energy program by evidence of their actions. They only want to support big business wind turbine or solar panels Fit programs. This is not the $12,000 +per year for the original contracts but we do win a lot more.
Enough to pay for the entire system.
This is not like winning the Lotto or becoming a Senator but we can maintain our honesty and still have a nice living.
It pays for a big part of our living expenses.
It is a much better option than some of those "deals out there" that offer up to $100,000 gross income. Go figure.
What did we just learn?
Going cheap we lose big time in the long run.
MicroFit Roof Mounted Solar Panel Optimization Summary With Flexible Solar
-I estimate +10% annual savings. Adds a panel monitoring system.
Independent testing has shown significant savings with optimizers - up to 24%
. Expect $12,000 life time savings (10%).
. Expect $12,000 life time savings (10%).
2.0 Choose a select Tier 1 Panel Manufacturer (details via FlexibleSolar only) +10-15%
Initial Testing Results show 15%+ or $18,000 maximum
3.0 Dynamic Array System -estimate up to +20% (add 2 kW to 10 kW). We have a 2 kW array that has good exposure to the sun from dawn to dusk. I estimate 2 to 3 times more power generation than straight south, east or west exposure because of this. It is like adding 2 -4 kW's on solar panels more to your system which you are not permitted to do. Standard East or West mounted fixed panels do poorly between October and March. On a test day on 24 Dec the array produced twice as much harvesting as statically mounted panels but 25% less than south panels. This will change as we get out of the winter conditions.
Initial Testing Results Show 2x's Static Panels for December -
This gives a minimum 2kW+ of installed capacity for East and West Panels
Summer 3x's not determined yet. Proof of concept is working perfectly.
On Target for $24,000 pay back or more.
You can do this.
4.0 Apply all of the above and put money in your pocket before program is ended and you miss out on getting your 20 year contract.
NOTE: The SolarEdge Optimizer system IMHO is much, much more flexible than micro inverters. Both contain Electrolytic Capacitors used to create AC power from DC. Both should start to fail after 10-12 years. Having them easily accessible reduces this cost by $1,000's of dollars. No one wants to go up on the roof and start removing panels every few weeks. It could take months to get some one to do that and you will be losing money. The micro inverters also are normally limited to 250 Watts where the SolarEdge give you a much better range and thus don't limit your design to low Watt panels. For example if I take Heliene's 335 W 72 cell panel on a 250 W micro inverter the max that I can get is around 250 Watts. Using a 350 Watt optimizer, I don't lose anything. Plus the Optimizers use Ceramic Capacitors which have a much longer life span. We also opted for the 20 year warranty extension with SolarEdge. Having a 25 year micro inverter warranty is not much good if you have to pay $200 + to have them replaced. Also the connectors for the micro inverters are so expensive that it costs you more to install that type of system.
Act NOW! ..................Before it's Too Late.
Engineering Installation Specification
I wrote an engineering specification which you can use with your supplier. That is what Mike Holmes would tell you to do.
Experience with Local Installers
After speaking with half a dozen or more people locally, we saw immediately that the FlexibleSolar people were the only ones interested in getting us the maximum return on our investment while maintaining the high equipment standards necessary for a 25+ year investment. It was a breath of fresh air working with Steve and Glen. I was working closely with a local PV manufacturer until they decided to ignore my engineering specification. It was a "bait and switch" operation that failed. Another supplier tried to put me down at one of my recommendations that will make us over $12,000 over the twenty year contract. Clearly these people are not customer focused. Another customer told me to stay away from Tigo optimizers as he had a poor experience with them. Perhaps they are better today. That leaves you thank God with at least one good company. Another big name string inverter manufacturer developed micro inverters verse optimizers. Again, 10 year warranty and a horrible location to maintain under the panel. They might have optimizers in about 2 years. Poor choice IMHO.
IMHO if you see one lie, run from those people. Mike Holmes says that 80% of contractors are in it strictly for the money and not for the customer. I am sure that Mike would like my ideal of an engineering specification to layout the quality of the work to be performed, and the payment method. We worked closely, and at time, correcting or adjusting my specification when warranted.
Discussion:
Beware of large down payments. I prefer a small 10% down and an immediate give a check for the equipment as soon as it is delivered to your house. This prevents people from grabbing and running away with your money. One guy suckered 15+ people into giving him $30,000 and he was gone. Another local company has over 300 home installed but not connected . Both the customer and installer should equally benefit from the payment specification. IMHO as soon as you get the equipment, pay them from you LOC. It will help to keep the costs down. All solar panel manufactures and I am sure all equipment suppliers want to be paid before releasing the goods. You simply want to prevent your self from paying large amounts of money and getting nothing in return. By the way, if that does happen, contact the RCMP as several of these cases can quickly turn from civil law to criminal law.
Get your offer to connect first from the Ontario Power Authority and then give out your money on the agreed schedule.
I hate to see thieves stealing from people and in many times retired people who can least afford the loss.
Hold back 20% until your are connected and your monitoring system is working. Then pay them.
Beware of hidden costs which your installer may or may not cover. Things like the building permit, engineering assessment of your roof, engineering review of the project, Hydro One's huge $1500. connection fee. Make sure that the MicroFit 22-26% Ontario content, CSA approved equipment, etc. FlexibleSolar are totally up front about any of these costs with you.
We went with Tier One manufactured solar panels, the best panel railing system, SolarEdge string inverters with optimizer to maximize the output of each panel and to give the ability to monitor each panel's output. We also have SS flashing over each attachment to the roof which will be a god send when the roof has to be re-shingled in 20+ years as they can be easily unbolted and re-used. Panel selection is very, very important. The good guys at Flexible Solar will make sure that you get the best panels with the best components built in.
A word about Inverters. You need to change the DC voltage from the panels to match the 240 V AC supply from Hydro. We went with string inverters with optimizers. We wanted to monitor each panel. String inverters IMHO must have optimizers on each panel. If a bird leaves it's droppings on one of your panels, it effects each panel in the string and lowers each panel to the lowest amount. Not a good thing. For a beautiful review of what happens when just a few leaves fall on one panel go to this SunPower mono link and see what they say. It is an eye opener. String inverters will need replacement or maintenance after 10-12 years. We went with the low cost additional 20 year warranty. We positioned the inverters in a semi protected area on the north side of our house next to the Hydro meter. I must add, IMHO all inverters using electrolytic capacitor will need replacement in 10-12 years and that includes the popular Micro-Inverters which in the end, cost a lot more money to install and maintain. I am NOT alone in this line of thinking. My system design and philosophy does reflect what I learnt as a Professional Engineer working for the local power company in operations.
IMHO my system will result in up to 20-30%
We went with the SolarEdge string inverter system with optimizer I researched micro Inverters and at the time IMHO believed that their 8000 hour capacitors would not last 100,000 hours as indicated by the failure rates posted by the string inverter manufacturer's who should know best. Remember, the maintainability is extremely important for a system that will last you a life time. It is the customer who must pay someone to replace the micro Inverter when they all fail after 12 years regardless of the posted 25 year warranty. We put the SolarEdge Inverters in a sheltered north side of our building next to the power meter. It keeps them in the shade all year long and parts can be quickly replaced when required. We opted for the 20 year warranty extension. It was a no brainier to me. Almost anyone can turn off the system and replace the capacitors or boards that simply pop in and out. Remember to wait 20 minutes after you shut the system down. There are all kinds of isolation switches: one on each inverter, a breaker for each inverter, a main disconnect switch from the grid.
If you have any questions, please contact me at KW Masters Photography and I will put you in touch with Steve or Glen at FlexibleSolar. Our contact information is above via the menu bar or click on our link. Pictures and stat's will follow as soon as they are available. You can even have our dynamic solar positioning system installed at your home. This extra is not cheap but the ROI is significant. I am a customer and not associated with FlexibleSolar. I assist them because I hate the sales practices of other people that I have seen in this business. We were careful and did not get ripped off. I do offer the dynamic positioning system to FlexibleSolar Only that I designed, coded and built so that you too can benefit from my research and work.
Thanks for dropping by. Give us a call if you like to talk about this (use CONTACT at top of page), or by drop in to discuss your project. Seeing is believing. An educated consumer is the best customer. We will have a monitoring system with this install. Drop us a line and tell us if you like what you see! Remember to tell Steve or Glen about this post if it helped you to make your decision to go with Flexible Solar.
NOTICE: We are on track to earning over $140,000 on our 20 year contract.
After the 20 years we will Grid Tie and sell power at going rates:
Reference: Here is a comparison with Tigo and Solar Edge
One of the First People to go Solar with Ontario's MicroFit:
Cost of Solar Power verse others - Good INFO Here
Getting the Panels with the Best Backing
Solar Panel Construction Component Studies
Dupont's Tedlar Backing
Alternatives to Tedlar Backing
More Alternative from Dupont for PV Panel Backing
Government Testing 15 year exposure of Backing
Another Backing Study
"The best orientation of your panels is on the angle equal to the latitude for a yearly average. Here in Windsor that is around 42 degrees."
ReplyDeleteThat is definitely *not* the case, as you say, common sense may not be so common.
The amount of power collected by a panel by otherwise unfiltered sunlight is the cosine of the angle between the sun and the panel. So for a south facing panel, for instance, in the morning it will collect almost no power, because the sun is 90 degrees off to the left.
Now we can't do too much about daily motion (more on that later) but we also consider the motion due to the Earth's tilt. In order to minimize the cosine angle, we would want the panels to be set up more vertically in the winter and more flat in the summer. So one would suspect, as you note here, that the best compromise is "half way" between the two extremes, or in our case, around 42 degrees.
Ahhh, but this analysis ignores the contribution of the changing amount of sunlight over the seasons. In the winter I normally figure for 2.2 hours of sunlight and 5.4 in the summer. If I set my panels to 42 degrees, then I will collect equal amounts of error in summer and winter -- but the summer error will "cost" me much more because I'm applying that error to twice as much input!
If you run all the math, you'll find the best yearly income angle is close to 30 degrees. This holds true for a surprising amount of the northern hemisphere. If you'd like to run the numbers yourself, I suggest googling up my article on "Green Apples" and then using the tools in that article to do runs in PVWatts at different angles.
"I estimate that this will result in harvesting 2 to 3 times more energy than a static roof mounted panel system"
I find this *very* difficult to believe, but I'd need more data to know for sure. What is the minimum and maximum angle for each set of panels?
The reason for my suspicion is simple. All across Ontario you will find dual-axis trackers that keep the panels pointed to within 5 degrees of the sun, or less, throughout the day. That is, the cosine error is basically zero while the sun is up. However, these devices, which are in effect "perfect", add a widely measured 30 to 35% more power. With a one-axis tracker, which is what I suspect you have, you should expect that to be closer to 20%.
Why so small? For a couple of reasons, but the main one is that there's simply not enough sunlight to improve on. Consider that the cosine of small angles is basically 1, and that's true for angles up to about 15 degrees (anyone recall this from their trig classes? And you thought it wouldn't come in handy!) So that means that a static panel will have two hours every day (15 degrees per hour rotation) when the error is basically zero.
Well, on average, there's only about two hours of sunlight a day in the winter. So no matter how perfectly you track, you can't improve input more than a few percent. It works much better in the summer when you have five hours to work with, but that's only a few months a year.
The other input is that the blue sky contains about 10% of the sun's total output, which means that even if you face your panels due north, they would still product power (something a little less than 10% for technical reasons I won't get into). So it's not like you get zero all those other times.
But more critically, this second point is only true on blue-sky days. On lightly cloudy days you might get as much as 50% of the sun's power falling on the panel, no matter what direction it's pointed. And it's pretty cloudy around here.
Once again, when you do all the math, you may be surprised to find that panels facing due east or west still collect a significant amount of power, perhaps 65 to 70% of a "correctly" oriented south-pointing one. Again, PVWatts is your friend here, and I'd be happy to walk you through a couple of examples if you'd like.
I am aware of PVWatts thank you. SolarEdge have a program also. I would like to have a 7/12 pitch roof, but we have what we have. 30 degres is better than my 22.5 degrees. It is a bit surprising that we can get 40-50 kW on a sunny day in December. Even on our cloudy days, all panels harvest the same. Perhaps you missed my point. On a microfit program you are limited to 10 kW DC installed. So how can I harvest more energy under these restrictions?
DeleteBy moving my East West panels they will double their output year round as per testing. Using South facing panels as a standard, east facing panels are known to out produce south facing panels when the sun rises more from the East. I observed the sun hitting my roof all last summer. This year I will track and capture the energy to see if I can exceed the south panels harvesting. Just due to longer exposures one can see that I will exceed the 2 x normal for East / West. That is like adding 2 kW more of panels in these locations. The sun would rise and hit my east roof around 6:30 AM and not hit the South roof until around 10:30 AM during the months from May to August. I am happy to see as East-West wain, South waxes.
Even in December we now harvest 70-75 % of South from East West. This will only increase as the sun rise more from the East as we approach June 21. I will post what I collect. Have a good look at our 24th of December's bell curve. It looks good to me.
Couldn't agree more with you about the cloudy weather. Try further north at the Bruce and you might never see the sun in the winter. Perhaps that is why they called it Grey County (and not after Lord Grey).
We will see how the pudding comes out (the proof is in the pudding). So far the only thing NOT proven is what factor to use with the dynamic positioning system. Two is minimum year round. During the major harvesting period what that number will be we will have to wait to find out.
In the hotter months, west facing panels tend not to do as well as east facing panels because of the higher temperatures. Perhaps poly will work better than mono as indicated on the web and providing better cooling to the panels will also help. Time will tell.
One can argue what is the best angle to put your solar panels. We are speaking about FIXED roof mounted panels not moving arrays. Today, Dec 24 2014 due to shading from neighbors houses, we don't really get to see the sun until after 9 am and much better at 9:30 am. At 10:30 am we have the West panels facing east as best as we can. The west panel output is equaling the best output from the South facing panels. At this time of year, the best angle of the sun for south is around 65.6 degrees. We have to live with our 22.5 degree roof. 65 degrees would look like sh#$@. FYI, yesterday we saw a peak output of 7 kW on a 10 kW DC system. You can apply your cosine of the triangle to this if you like. Things like cloud cover and shorter days have a big effect at this time of year. For example, in May we expect that the best angle will be 22.5 degrees and not 65. I address the sun rising in the east by raising the west panels. In December, the sun rises SE and not east so your 90 degrees is way out. It helps the South facing panels to work earlier and longer. There are many things that effect your panel output. You must be correct. common sense is not so common. This problem is varies throughout the year. As Engineers we are forced to make compromises. One is a happy wife. Another is practicality. It is published on the web that the best compromise to put your panels on a fixed roof is equal to the latitude or 42 degrees in our case. It is better to optimize your system from March to October. I would like a higher pitched roof but that is what we have. Merry Christmas to you all.
ReplyDeleteI love math and especially geometry. We can do all the calculating that we want. We then need to go outside and visually look at what is happening and look at the output of the Inverters. By 9 am because the sun is rising in the South of East NOT East, we were producing 2 kW. By 10:10 this had risen to 5 kW. By 11:20 am 6 kW. One goal is to spread out the histogram to as high and wide as possible. Normally you need to add East and West panels to do that. Solar noon is around 12:20 pm so we will be harvesting power for 7 hours + if the clouds stay away. 60% output in the Winter is great. I had to back off the west array because of wind. Trackers shut down when the wind exceeds 20 mph. I could see the 100 W decrease in production because of this. I increased east's orientation and made up for the difference. I only have a 3 position array. It is a compromise. I am playing with the system as this is the best day that I have seen so far. Yesterday was good. It was reported to me that we ranked number one of 8 systems locally. We must be doing something correct. I like your analysis .
ReplyDeleteWhen I speak of 2 to 3 times I am referring to the output from the East and West panels only (20 % of total installed capacity). Not from the south or complete system. I estimated a 20% increase which may be conservative. Simply put I am trying to get the panels to have more exposure over the entire day. It is the period from mid March to mid October which gives us more sun and at a higher angle of attack. So far moving the panels on the east and west arrays is working great provided that the wind and clouds co-operate. IMHO if you can get your east and west panels to produce power equal or so to the south in December, you are doing something good. Production will improve significantly after March as we slowing see the sun moving from south of east to east (21 June). I can see how a little shading from my old pine trees is robbing us of considerable generation. They will be cut down shortly. Harvesting solar energy is grabbing little bits when ever you can. Today we hope to have 7 hours of production and not your forecast 2 hours. Some days we would love your 2 hours as we get very little from a dark overcast day.
"When I speak of 2 to 3 times I am referring to the output from the East and West panels only (20 % of total installed capacity)."
ReplyDeleteI assumed as much, but again, I believe that is much higher than what you should expect.
I assume the "flat to roof" angle is 22.5 degrees based on the text above, but how high can they go?
Our east west panels average output is about equal to the south output per year. We doubled the output of the east/west panel lying flat on the roof. Their height is limited to the 12 inch actuator that I found locally. West works better than east for some reason unknown to me. In the summer they outproduce south panels by 30% or so. Other factors are now applying making analysis impossible ie we saturate the inverters at max power for many hours.
DeleteThis blog is a WIP. I do appreciate all worth while comments. That is how we learn and improve ourselves. By reviewing the panel harvesting from the East and West panels in December, I am able to determine that moving the panels resulted in more that a 2x improvement in solar harvesting. Normally the harvesting from east and west in December is quite low. I saw ruffly 1/3 that of a south facing from a static east panel. In total the east and west panels produced about 75% of south. Excellent results for this time of year. What will happen in the summer when the sun does indeed rise from the east, we well see what happens. From observation last summer, east roof was getting sunlight at about 6:30-7 AM South roof start at about 10:30 AM. With the array, West will now produce first a good 4 hours before south. The same thing reverses in the afternoon. I expect east and west to blow south's production away due to orientation and extended time of exposure. Time will tell. Season's Greetings to you all and a happy new year.
ReplyDeleteHow high can the panels go? This depends on your system design. I haven't measured the angle. It would appear to be about 40 degrees. I do worry about wind loading and still have to install safety chains and an automatic shutdown based on wind speed and some stiffeners to remove any deflection from wind.
ReplyDeletelike your style of blogging. I added it to my favorites blog page list and will be checking back soon.Home solar panels
ReplyDeleteAwesome ! i really found very informative article here and bookmarked this blog. Thank you.installers
ReplyDeleteVery informative, thanks. we got the pitch from grasshopper for them to install and our roof. i told my wife to wait and i would investigate. do you know any installers or reputable dealers in Richmon Hill , T;oronto Area. Thanks Roddy
ReplyDeleteThanks for this blog. A question about CRA Treatment of Loan Interest with MicroFIT...
ReplyDeleteI understand the CCA claim each year is limited by total PV revenue (that is depreciation may not be used to create a “business” loss). I was wondering what your experience is with regard to tax write-off of loan interest on “money borrowed to earn investment income,” for those who wish to borrow the full or partial cost of the capital purchase. Specifically, can the loan interest be an expense further offsetting personal income taxes, creating a loss on the PV investment and essentially making the loan “interest free” (since you get the taxes back)?
We do not post a loss. IMHO the interest cost on any loan can be written off but is less than what you generate. With the right set up you generate more income than what it costs you to borrow the money at today's rates. It helps us a lot. We borrowed the full amount and are still very happy. With the wrong roof orientation and too high installation costs you can lose money. Be careful. Only Flexible Solar worked with us honestly. All others were not interested in us maximizing our output. The ROI is about 12% on investment. You have to be careful and do the math correctly. At 3.5% loan monthly interest payment is a lot less than what you generate. You still have to have a house which also normally has a mortgage which is also a cost to generate an income.
ReplyDeleteYou can only write of expenses related to the micro fit and NOT related to your income. So you can not lower your income taxes.
ReplyDeleteGreat pleasure reading your post.Its full of information, thanks for sharing.
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