Solar FAQs

What is solar energy?

Solar energy is radiation from the Sun that is capable of producing heat, causing chemical reactions, or generating electricity. There are a variety of ways in which the sun's energy can be harnessed including:

Why use solar energy?

Solar Energy is a renewable and plentiful resource that has few limitations. Harnessing solar energy is comparatively cheap and the energy produced can be used directly at the source as opposed to traveling great distances. The two main limitations are shading from nearby trees (nature's solar panels), and that the sun is an unreliable generator, meaning solar production/effectiveness is heavily skewed towards summer months.

Net-Metering or the current Self-Generation Offset program allows a grid-tied home to produce power which feeds the house first, and any excess power is then sent to the grid which is recorded by a bi-directional meter. This meter will provide credits that can be used at night and after a summer's worth of production you can offset the winter's use as well. A more detailed explanation on Net-Metering and the Self Generation Offset Program can be found here (link!)

A Net-Metered Solar PV system uses the grid as an "infinite battery bank," where your excess summer production can be banked for winter.

Is the design process for an on-grid system the same as that for an off-grid system?

The design process for an on-grid system is very different than that of an off-grid system. An on-grid system typically does not have batteries and certainly does not require batteries except in case of a grid-outage. An off-grid system requires an in-depth knowledge of the electrical loads and battery maintenance by both the installer and the customer. In general, off-grid systems require more planning, consultation, and industry knowledge. They are also more expensive (mainly due to the cost of the batteries) and often require more existing infrastructure such as non-electric heat sources or hot water sources.

The design process for a grid-tied system is relatively simple, as the installer does not need to know what the electricity is being used for. A grid-tied system also does not need to meet the entire electrical demand of the property. Most installers use satellite imagery and your historical annual kWh usage (commonly found at the bottom right-hand side of your NSP bill) to determine how many panels can fit on the roof or ground and what the production will be for that size of the system.

Can I install my own solar energy system?

Some parts of a solar installation can be done by anyone, but anything involving electricity should be handled by an electrician. Both on and off-grid solar PV systems need to be installed by a Red Seal electrician and inspected by Nova Scotia Power or the local electrical inspectors.

In general, racking and mounting panels, building a ground mount frame (depending on local building code), trench digging (if required), can all be done by someone with the skills and safety equipment/certifications to do so.

Will a grid-tied solar system power my home during a power outage?

A Solar PV system is capable of producing more power than your property uses in a day; this excess goes back to the grid. During a power outage, you cannot export power to the grid as it could injure line-workers, so all grid-tied Solar PV systems are designed and required to shut down automatically as soon as they stop detecting the grid. This is called "anti-islanding." Additional components can be installed that allow a part or all of a grid-tied solar PV system to operate during an outage but this typically requires a significant investment and is not trivial.

How long will my system last?

A Solar PV system will last as long as its component parts do. Solar PV Systems can broadly be broken down into three categories, each with varying warranty lengths:

In general, a solar PV system is expected to last 25 years, and potentially much longer.

My building's roof needs replacing soon. Does it make sense to combine the installations?

Shingles are damaged mainly by the sun, so anywhere covered with solar panels should extend the lifespan of the shingles underneath indefinitely. However, if your roof needs to be replaced in the next few years, doing it before installing solar panels is an excellent idea. If installing a metal roof, it's advisable to use a gauge of steel that can withstand the work being performed on it. If you're using "penetration free" racking such as S-5! clamps on a standing seam roof, make sure to use 26 gauge steel or better as you're relying on the structural integrity of the steel itself rather than the roof trusses to hold the system down.

Is my home a good site for solar?

Many homes are good locations for solar panels, which is one of the strengths of the technology. Ideally, you want a south-facing roof that's not too architecturally complicated. Other considerations would be self-imposed shading from the building itself (dormer's/second stories) or nearby buildings and shading from trees which can turn a theoretically perfect location into a non-viable one. You know your home better than any contractor, so take the time to walk around and look at the roof with a critical eye and think about where you would place the panels to get the most sun.

What is a Solar Energy System Design Brief?

A Solar System Design Brief, or solar proposal/quote is what a solar installer will provide a potential client. Typically, a proposal will include the number of panels that can fit on a roof in a viable configuration either done through satellite imagery, drone photos, or physically measuring the roof. It will have a calculation for the annual kWh production of the system often compared against an existing power bill. It should list the brands/model numbers of the equipment, particularly panels and inverters.

Solar proposals are often presented as a long-term investment. The idea is that the amount of power produced should remain roughly the same year to year, but the "escalation rate" or the rate of power you pay for will increase over time. Historically the escalation rate has been 3-3.5% per year over the past 10 years, however, an installer is free to set whatever escalation rate they think best on their proposals.

What are the effects of snow on panels?

Snow on the panels will partially or completely shut down PV power production until the snow comes off. When the snow comes off, it does so exactly like a metal roof (it slumps), so if you're filling the roof all the way to the edge with solar panels, a good consideration would be to ensure that there's nothing below that could be damaged/injured by falling snow or avoid placing panels too close to the edge.

In terms of production, solar power is heavily skewed towards the summer months, so anything you're able to get out of the panels in the winter is great but not expected.

Is Nova Scotia a good place for solar energy?

Nova Scotia is absolutely a good place for solar energy, as is most of North America. However, we have some unique aspects that make solar here a great investment. Nova Scotia has a culture of environmentalism and strong backing from the provincial government. It is also one of the only places where kWh for kWh* (the rate you pay for power is the same rate the utility must pay you for your power)* is provincial law instead of a contract with a utility. We also have some of the highest utility rates in Canada which means the value of a kWh produced in Nova Scotia is higher than elsewhere.

I'd like to be a solar contractor / carpenter / technician. What is my first step?

There are a number of different approaches to solar contractors/installers but in general, it's a labor-intensive career that will require heavy lifting (panels can weigh up to 70lbs) and being comfortable working on a roof. Getting fall arrest training and equipment would be the recommended first step. Other suggestions might be reaching out to existing companies or taking an educational course like NSCC's Microcredential in Solar PV - NSCC Solar PV Systems Design.

Do I have to clean my solar panels?

Generally, we get enough rain in Nova Scotia that you probably won't have to ever clean your solar panels. However, dirt, pollen, and leaves or other obstructions can impact solar production and if this is the case you may wish to clean the panels if it is safe to do so.

What is the optimum tilt angle for my solar panels?

The optimum tilt or pitch will heavily depend on the azimuth (compass orientation) of the panels and the time of year. Because we're in the Northern hemisphere, the ideal location for solar panels is a South-facing roof. Anywhere from South East to South West is excellent, and even due East or West roofs can be a good spot for panels if the pitch is not too steep.

If we're talking about a perfect 180-degree South facing roof, the best pitch in the winter is steeper at around ~45 degrees while the best pitch in the summer is shallower at around ~25 degrees. This is because the sun is higher in the sky in the winter and the best "angle" for the sun's rays to hit the panels is 90 degrees (perpendicular).