The OPA has a 50MW procurement target that is rapidly filling up. By the end of May we expect the capacity to be allocated, and the MicroFIT rate (the price paid for your power) will drop again, probably by about 10 to 15%. Call us today to get your MicroFIT application started.
MicroFIT 2.0 defines the 'nameplate capacity' as the larger of inverter size or array size. in other words, both your inverter and your PV array must be less than or equal to 10kW (=10,000W). Unfortunately, and strangely, this decision seems to have been made without the benefit of PV design experience.
Most contractors and system designers will be trying to hit exactly 10kW of array size (for systems unconstrained by roof area). This looks good on paper, but may result in poor system performance over the system's lifetime.
Common PV module sizing includes 250W modules, so 40 x 250W = 10kW quite nicely. Arrays with 40 modules (regardless of module size) will be designed in 4 strings of 10 modules. However, for most grid-tied inverters strings of 10 will result in poor hot weather performance, a problem that will get worse as the modules age. Such a system could spend a significant portion of each hot day not producing at all, as the array cannot sufficiently drive the inverter. (Just think of this past July: hot and sunny.)
Strings of 11, 12, or 13 are a much better design and that's what we use in our designs. So a system based on 44 x 225W modules = 9.9kW is a more robust design than 40 x 250W = 10kW. Similarly, 39 x 250W = 9.75kW is more robust than 40 x 250W, even though it's 250W smaller. In fact, strings of 13 represent the best design, maximizing system efficiency and prolonging inverter life.
String sizing issues can be eliminated all together by using micro-inverters. Whether or not micro-inverters are worth their premium price will depend on your site details.
Overall preferred system design will be based on your site. Call us to set up a site assessment and we can recommend a system design for you!
Yorkshire Valley Farms is a producer of certified organic chicken. The farmers, Tom Ahrens, Tony Ambler, and partners, have ambitious and exciting plans for broad scale availability of organically grown chickens. (Their chickens can now be purchased at Loblaws stores across the province.) To support these plans they are building a number of new barns and elected to include a FIT PV system on the first new barn.
The barn was built in the fall of 2010 with the first batch of chicks arriving in November. The roof-top portion of the solar project had to be finished well before the chicks' arrival so as to not disturb the chicks with construction noise.
This project includes 540 Conergy P235 modules and 270 Enphase D380 micro-inverters. Enphase was selected as the project inverter in part owing to their availability as Ontario Content within the timeframe of the project. The array was broken into 3 sections, each feeding its own Enphase Line Communications Filter and Envoy Communication Gateway. The Envoy allows module-by-module performance and error monitoring for maximizing long term system performance.
The building design was optimized for solar in 2 ways: roof pitch was increased for improved PV performance, and roof structure was designed to accommodate vertical PV mounting rails and a landscape module orientation.
The site had great access all along the southern side, and was only a single storey high. This allows us to use a telehandler (sometimes called a zoom-boom) to retrieve full skids of modules from the storage trailer, move them to the installation location, and place the entire skid right at working height at any point from the eave to the top of the roof.
This project encountered many bureaucratic hurdles along the way. This owes largely to the degree to which it was pushing the envelope in the province: Among the first FIT projects to reach commercial operation; The first Enphase FIT project to reach commercial operation; The first FIT project for this Hydro One service region
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When constructing its new building in downtown Peterborough, the YWCA of Peterborough, Victoria, and Haliburton decided to incorporate a number of green features, including a 10kW roof mounted solar electric system.
The Y and its architect turned to Generation Solar for advice on how to best incorporate the solar array into the new structure. We recommended the use of standing seam metal roof so as to permit a penetration-free roof-top installation and the idea was endorsed by the Y's building committee.
The finished installation made use of standing seam roof anchors by S-5! installed on each and every roof seam. The roofing installation itself was reinforced to accommodate the solar array based on design work by Generation Solar. Wiring was slipped up under the roof cap for a completely penetration-free installation, ensuring that, for the life of the roof, there will be no leaks associated with the solar installation.
The installation was complicated by the proximity to the sidewalk -- we knew we would need to work on the sidewalk, so we secured a permit to close the sidewalk. The articulated boom we used for roof access caused some depressions in the recently landscaped boulevard, so we regraded and resodded once we were finished.
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Take one Canadian Art landmark, add a steep steel roof, 60 feet in the air on a sloped site, and a 15kW - 3 Phase solar electric array and what do you get? The McMichael Canadian Art Collection project.
The McMichael Canadian Art Collection houses Canada's largest collection of Canadian Art most notably the best collection of Group of Seven work in the world. Directly under the PV array is gallery space - a roof leak could ruin a priceless work. For this job, a Standing Seam Metal Roof was used. It allowed us to fasten our racking without making a single roof penetration. We attached directly to the standing seam with special clamps made by a company called S-5!. The S-5!s with a standing seam metal roof are a premium combination but if potential roof leaks will keep you up at night you might want to consider them.
The second challenge with this job was the height and steepness of the roof combined with the sloped site. An aerial lift or crane would not work on this slope. To deal with this we used custom scaffold along the entire length of the eave below where we were working. This gave us a staging area for equipment and tools as well as an added measure of safety for those down below if a part or tool was to slide away on us. This type of work environment requires extra planning to ensure few trips up and down the scaffolding as this can add tremendously to installation time and installer fatigue.
Our last big challenge on this job was dealing with the irregularly shaped roof surface. The wall construction is log with stone piers in between. Over time, the logs settled, but the stones didn't. This left a terrible hump in the roof above the stone pier. We felt that the lines of the solar array would further accentuate this hump so we used a racking system that allowed us to 'mellow' the hump. It was a long and systematic process but it worked out well in the end.
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The Kelly Residence is a classic case of perseverance and performance. It's a 9.66kW high efficiency squeeze that started in the Spring of 2009.
Brian and Lynne Kelly first contacted us shortly after the initial microFIT announcement in March 2009. They liked what they were hearing about the Green Energy Act and Feed in Tariffs for solar electricity production. The Kelly's wanted to take part with a 10kW system on the roof of an addition to the family's home. We kept in touch through the turbulent beginnings of the program and regularly sent each other updates when we heard new information.
I had the roof measurements and knew it was going to be a tight fit for 10kW, but as new modules with different dimensions and efficiencies became available I sized them up for suitability.
When the program officially became available in October 2009, Brian was one of the first to get his contract application in and Generation Solar had become authorized to install the uber efficient and highly coveted Sunpower line of modules. The Sunpower 230W panel was a perfect fit. With its 18.5% module efficiency we were able to hit 9.66kW - a power density of over 180Watts/square metre!
Brian and Lynne Kelly's contract came through in the spring of 2010. In June, the family was hosting a family re-union weekend with 300 guests. The goal was to get this system connected in time for the re-union.
The Kelly home is beautiful. It's a delightfully crafted old one-room schoolhouse converted to a home in rural Peterborough with very well manicured gardens. Brian warned me, with a fearful husband's smile, that Lynn's gardens were not to be disturbed!
We set to work in May. We used a 51' articulated aerial boom to access the 2nd storey 12:12 pitch steel roof and light feet to minimize our impact on the gardens. We had the complete system up in just over a week. After passing electrical inspection, the connection authorization was issued to the utility. With 2 days to spare before the family re-union weekend the system was connected and commissioned - and not a single guest complained about the gardens!
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