Is Your Home or Business Solar Panel Ready?


A question we encounter quite frequently in talking to home and business owners is: Does solar work for my roof? While solar systems work on most roofs the answer sometimes is not that simple. This is why I am going to shed some light on this issue to give you some tools for your own roof assessment.

1) Roof Pitch

Roof pitch for solar panelsThe roof pitch is one of the factors that influences how much energy your solar modules will absorb. Keep in mind that we are trying to find a good balance between summer/winter. While some people are leaning towards your location’s Latitude as the optimum angle, there are others that deduct a number from your Latitude so the modules perform better in summer, when the bulk of the harvested energy is available. The reason why the optimum pitch is often below the Latitude for a location is the fact that a typical solar system in the northern hemisphere will harvest the majority of energy from April to October. Thus the modules need to be angled a bit less to hit the optimum for when the sun declination (the angle of the sun rays in relation to the equator) is quite high. Most industrial units have flat roofs and are ideal for a solar installation as the angle of the panels can be adjusted. At the end one should not put too much emphasis on this topic since most residential installations are roof-parallel. This means the pitch is given by the existing roof slope and can not be altered.

2) Orientation

roof orientation for solar panelsThe best orientation of a solar module is facing towards True South. This is ideal as you can see in the diagram, the sun’s path changes from season to season. But with the cost of solar modules coming down, roofs that are facing towards the East or West, and even in some cases North-East/North-West exposures are still producing good return rates. Businesses with flat roofs are ideal as the solar power system can be positioned to suit the sun’s path irrespective of the buildings direction. How important this maximum efficiency of a solar system is, depends on the feed-in-tariff program and the overall system cost.

3) Shading

solar panel shading on the roofShade on a solar module is not a good thing and must be avoided. Modules should only be mounted on roof spaces that are not affected by partial or full shading during the core hours (10am to 4pm) of a day. Even the shadow of a telephone wire can significantly reduce your energy production. It also needs to be noted that there is no inverter technology available that can generate energy from a shaded module, contrary to what micro-inverter supporters sometimes claim.

4) Temperature

Solar modules can operate even at very cold temperatures. In fact the electric efficiency of a module increases the lower the temperature is. Most modules are rated for as low as -40 degrees C. Due to this effect you can expect very high power generation on crisp cold but clear days. Great for northern climates like ours in Ontario.

5) Dust and Dirt

cleaning solar panelsModules have a self cleaning effect when it rains. The tempered glass surface does not allow dirt and dust to stick to it once rain water runs over it. There may be exceptions when additional cleaning is required, i.e. farm operations or locations near major highways. Ensure that demineralized or rain water is used for the cleaning. Otherwise you may get calcium build up, negatively effecting the amount of light that gets through to the solar cell under the glass.

If you think your roof is solar ready or are still unsure then seek the advice of a reputable solar installer. Most companies provide you with free solar assessments and advice.

Stand Up for Solar


stand up for solarThe Ontario government has made several ground breaking advances in promoting the development of renewable energy through subsidies with the FIT and microFIT initiatives. So popular has the program been that the Ontario Power Authority (OPA) has been overwhelmed with applications from home and business owners. This blossoming development has seen the renewable energy capability of Ontario increase to 1,300MW — enough to power more than 300,000 homes, making it one of the 10 solar hotspots in North America. The OPA has further guaranteed development of the Ontario economy by insisting that 60% of the solar power systems installed in the province be made locally.
stand up for solarThe insistence on local content has made the province a viable and attractive prospect for solar companies. Companies like Canadian Solar, Silfab SpA and others have opened plants in Ontario in recent months, creating much needed ‘green collar’ jobs. The increase in contracts has seen solar installers popping up like mushrooms. Solar installers provide thousands of jobs in the solar power industry.
Another incentive for growth is the sharp decline in prices for solar power systems; PV solar systems cost half of what they did in 1998. A recent study by Duke University showed that the ballooning costs of nuclear plants last year resulted in the crossover eagerly anticipated by renewable energy companies for decades; solar is finally cheaper than nuclear! But trouble may be on the horizon. The McGuinty government has shown a strong preference for nuclear and gas electricity production, refurbishing two nuclear reactors at the Bruce power plant with plans to build two more. The opposition has shown strong resistance to the FIT and microFIT initiatives, threatening to scrap the programmes altogether. The OPA has also hinted at future reductions in FIT and microFIT subsidies which would slow solar power installations dramatically and lead to the closure of solar companies and a loss of jobs in the province.
The Canadian Solar Industries Association (CanSIA) represents various interests in the solar industry. Said ex-chair David Eisenbud; “By 2025, solar energy expects to be widely stand up for solardeployed throughout Canada, having already achieved market competitiveness and no longer needing government incentives. By 2025 solar will be supporting more than 35,000 jobs and displacing 15 to 31 million tonnes of greenhouse gas emissions per year, while providing a safer, cleaner environment for generations to come.” All this will be jeopardised should FIT and microFIT subsidies be halted or altered.
When the German government threatened to reduce solar funding, members of the solar industry and local communities campaigned to have their subsidies extended. So great was the support that the German government revised its plans. CanSIA is hoping to drum up similar support. To this end, they are launching the Stand Up for Solar campaign. A website,, allows you to create awareness through social media sites like Twitter and Facebook and email or tweet your MPP to voice your support for the solar industry. If you want the government to vote for solar in the October elections, you will have to join those in the solar industry to make a stand. 

Go to the website, donate funds or post the site on your social media outlets to spread the word.

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