Ground-mount solar panels in Ottawa and across Ontario

KAJK Constructors provides a suite of services to design, build, repair and maintain a variety of ground mount solar panels. These ground mounted solar panels are an alternative to roof mounted solar panels: they are often much more efficient than rooftop solar panels and can be the right choice for both residential and commercial applications.

Ground mounted solar arrays are known to outperform their rooftop counterparts. Here's why you should choose a ground mounted solar array if one is available for your location:

It is worth it when the roof is the limit. A ground mount earns its extra cost where the roof faces the wrong way, sits under trees, is too small or too flat, or needs replacing before the panels would wear out. In open ground the array can face due south at the best angle, grid-tied or paired with battery storage.

Natural Resources Canada's figures for Ottawa show what that is worth. A south-facing array tilted between about 30° and 45° yields 1,200 kWh a year per kW of panels. The same panels lying flat yield 977, so the right tilt is worth about 23% (our arithmetic on NRCan's table).

If your roof already faces south at a decent pitch and has 25 years of life left, the gain is small and the roof usually wins on cost. NRCan's Photovoltaic Ready Guidelines call roof-mounted equipment the most cost-effective way to install solar in most homes.

We design and build all three. NRCan's monthly Ottawa data shows the trade-off in kWh per kW of panels; NRCan notes its monthly values do not account for snow.

Ontario's Building Code leaves frost depth to local experience (Division B, 1.1.3.2) and sets 1.2 m as the minimum foundation depth for buildings in clay or soils not clearly defined (Table 9.12.2.2). A ground mount is light, so frost pushing its posts up usually governs the design more than weight does.

Researchers measured this in Ottawa. In 1969, E. Penner and W. W. Irwin of the National Research Council set steel pipes 8.9 cm across to 1.5 m in Leda clay on NRC land in Ottawa and recorded uplift of about 2,700 kg over two winters. Their conclusion: a footing below the depth of frost penetration does not ensure stability if the soil freezes to the post.

Helical piles and ground screws hold against that uplift with a helix anchored in unfrozen soil. CHANCE, a helical pile maker, says to place the helix below maximum frost penetration plus at least one helix diameter, and cites the Canadian Foundation Engineering Manual's adfreeze value of 100 kPa for steel in fine-grained soil. A 2015 paper on Ontario solar farms by Kibriya and Tahir reports piles lifted by frost where contractors shortened them to save cost.

Ottawa's Zoning By-law 2026-50 is generous to ground-mounted solar. Section 202 sets no maximum size for ancillary solar energy generation in the N1 to N6 neighbourhood zones, and the same in village and rural zones, provided the ground-mounted devices sit in the rear yard and the ground under them is soft landscaped. The City's Development Information Officer can confirm setbacks and height for your lot before the design is final.

The building permit question is narrower than for a roof. Ontario's 2024 Building Code designates solar collectors mounted on a building with a face area of 5 m² or more (Division A, 1.3.3.5); a ground array is not on that list. Norfolk County, for one, states that no building permit is needed when the panel is not installed on a building. Ottawa's own solar page covers building-mounted systems only, so a ground mount's permit status is confirmed with the City for the specific design. The electrical side needs an ESA permit either way.

A ground mount adds a trench between the array and the house or service, and its length feeds straight into the power-loss calculation.

Ottawa sits at 45.4° N with about four months of snow cover a year, the figure given for the University of Ottawa's SUNLAB test site in the IEA's 2021 bifacial report. NRCan notes that arrays at 15° or less shed snow poorly. A ground mount can be set at any angle, high enough to clear drifts and within reach of a roof rake.

Snow has an upside too. Researchers at Queen's University found that snow losses depend on tilt and panel technology, that older prediction methods overstate them, and that bright snow around an array can raise yield, most of all for steep arrays (Andrews, Pollard and Pearce, Solar Energy, 2013). The IEA report lists snow albedo at 0.55 to 0.98 against 0.15 to 0.26 for grass. That is why bifacial panels, which also collect light on their back face, are worth pricing for an open-field array.

Ground mounts are also built at farm and industrial scale. KAJK reports it “worked on over 150MW on various industrial ground mount solar farms” in its 2016 to 2019 timeline. For a business or farm array above 12 kW AC in Hydro Ottawa's territory, connection starts with a Preliminary Consultation Information Request, answered within 15 days, then a Connection Impact Assessment with drawings stamped by an Ontario professional engineer. See commercial and industrial solar for the business side, or residential solar for rooftop homes.

To find out whether your lot suits a ground mount, book a free assessment: (613) 869-8254.