Solar Panel Estimate Calculator

How to use this calculator

The estimator turns a single number — your monthly kWh — into a full project view: system size in kW, annual production in kWh, gross C$ cost, net cost after the Greener Homes Loan and provincial rebate, year-1 savings, payback, and a 25-year cumulative figure with tariff escalation built in. Use it before paying for an in-person CanREA quote.

Inputs:

1. Monthly electricity use (kWh) — average the last 12 bills. NRCan Survey of Household Energy Use shows Canadian households averaged 11,135 kWh/yr in 2021, but ranges from 6,500 kWh/yr (Toronto, Montreal, Vancouver — gas heating) to 22,000 kWh/yr (rural Manitoba/Saskatchewan electric baseboards). Heat-pump retrofits add 4,000-7,000 kWh/yr.
2. Target offset (%) — under provincial net-metering policies, banked credits typically expire annually (Ontario IESO 11-month rolling balance, BC Hydro NMA annual reset, Alberta Micro-Generation Reg lifetime carry), so sizing above 100% is wasteful. Off-grid sizing requires battery autonomy modelled separately.
3. Peak sun hours/day — NRCan PV Availability dataset annual averages: Regina 4.5, Calgary 4.5, Saskatoon 4.4, Winnipeg 4.3, Edmonton 4.1, Toronto 3.8, Ottawa 3.8, Montreal 3.7, Halifax 3.6, Vancouver 3.0, St. John’s 3.0, Whitehorse 3.4, Yellowknife 3.5.
4. Installed cost per watt — the all-in CanREA-member turnkey price including DC and AC equipment, racking, permits and ESA/SaskPower interconnection. 2026 Solar Industry Magazine median for residential is C$3.20/W on systems 6-10 kW, falling to C$2.85/W on 12-15 kW. Below C$2.65/W typically signals tier-2 panels.
5. Federal/provincial rebate (%) — 25% default approximates Greener Homes Loan effective subsidy via 0% interest. PEI residents enter 35% (Solar Electric rebate), NS residents 18% (SolarHomes C$0.30/W).
6. Electricity rate (C$/kWh) — the all-in retail rate from your bill: BC Hydro Step 2 C$0.151/kWh, Hydro-Québec D-Tier C$0.0851/kWh, Toronto Hydro TOU peak C$0.182/kWh, ENMAX deregulated default C$0.18-C$0.22/kWh, SaskPower residential C$0.166/kWh, Manitoba Hydro Tier 1 C$0.097/kWh.
7. Annual rate escalation (%) — provincial regulators have averaged 2-3.5% nominal growth since 2010; 2.5% is defensible.

How the math works

annual_target_kWh   = monthly_kWh × 12 × (offset% / 100)
system_kW           = annual_target_kWh / (peak_sun_hours × 365 × 0.78)
annual_production   = system_kW × peak_sun_hours × 365 × 0.78
gross_cost          = system_kW × 1000 × C$/W
net_cost            = gross_cost × (1 - rebate% / 100)
year_1_savings      = annual_production × C$/kWh
simple_payback      = net_cost / year_1_savings
lifetime_savings    = sum over 25 years of (production × (1-0.005)^year × rate × (1+esc%)^year)

The 0.78 derate follows NRCan CanmetENERGY testing for Canadian conditions, accounting for snow cover (3-7%), winter low-irradiance underperformance, and -25°C performance bonus on cold sunny days that partially offsets summer high-temperature derate.

Worked example for an Edmonton home using 7,500 kWh/yr at C$0.20/kWh:

• Annual target: 7,500 kWh
• System size: 7,500 / (4.5 × 365 × 0.78) = 5.85 kW
• Annual production: 5.85 × 4.5 × 365 × 0.78 = 7,500 kWh
• Gross cost at C$3.20/W: 5,850 × C$3.20 = C$18,720
• Net after Greener Homes (effective 25%): C$14,040
• Year-1 savings: 7,500 × C$0.20 = C$1,500
• Simple payback: C$14,040 / C$1,500 = 9.4 years
• 25-year lifetime savings (2.5% esc): ~C$48,200

Canadian payback ranges by province (2026)

Solar Industry Magazine + provincial regulator data:

Sources: Canadian Renewable Energy Association (CanREA) member data 2025, NRCan PV Availability Maps, provincial regulator default rate filings 2025-26.

What lowers Canadian payback

• Greener Homes Loan ($40,000 at 0% over 10 years) — the cost of capital is normally 4-6% in Canada, so 0% saves the equivalent of 25-30% net present value
• Net billing in regulated provinces — 1:1 retail credit on every exported kWh, well above the 4-8c/kWh export tariff in deregulated Alberta or grid-purchase agreements
• TOU tariff arbitrage in Ontario — sized to overlap peak (11 a.m.-5 p.m.) the system displaces C$0.182/kWh peak rate, not just average
• Cold-climate temperature bonus — Tier-1 panels gain 0.3-0.5% per degree below 25°C, so a -10°C clear winter day at 60% irradiance still produces near nameplate

Pair this with the cost calculator, payback calculator, and ROI calculator

The estimator gives the headline numbers; the cost calculator drills into C$/W and adders; the payback calculator separates simple from discounted payback (with cost of capital factored in); the ROI calculator presents the project as an IRR comparable to a TFSA-held GIC ladder.

Sources

• NRCan Photovoltaic Availability Maps — peak sun hours by region
• CanmetENERGY Solar PV Knowledge Centre — performance modelling
• Canada Greener Homes Loan — 0% interest financing
• PEI Solar Electric Rebate — provincial incentive
• Nova Scotia SolarHomes Program — provincial rebate
• Solar Industry Magazine 2025 Canada residential pricing — installed price data
• HomeStars Solar Pricing Index — installer benchmarking