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Off-Grid Solar System Calculator (Canada)

Free Canadian off-grid solar calculator. Sizes PV array (kW), battery bank (kWh), and inverter (kW) from daily kWh load using NRCan irradiance data and CSA C22.1-aligned design.

Off-Grid Solar System Calculator

PV array (kW DC)
3.3 kW
Usable battery energy (kWh)
27 kWh
Battery bank (kWh nameplate)
31.6 kWh
Inverter (kW continuous)
4.4 kW

How to use this calculator

The Canadian off-grid calculator above takes your daily kWh load and NRCan-derived peak sun hours and returns three numbers: PV array size in kW DC, battery bank capacity in kWh nameplate, and inverter continuous kW rating. Units are mixed metric/imperial (Canadian convention: m² for area, AWG for wire, kW for power).

  1. Daily energy use (kWh) — your average daily AC load. Pull it from a recent utility bill (monthly kWh ÷ 30) or sum nameplate watts × hours-on. Statistics Canada’s Energy Use Database puts the national residential average at 30 kWh/day driven by electric heat in Quebec, BC, and Atlantic Canada. Off-grid Canadian properties typically run 8-15 kWh/day because heat is wood/propane/oil and high-draw electric loads are minimised.
  2. Peak sun hours (h/day) — NRCan’s Photovoltaic Potential and Solar Resource Maps annual averages: Toronto 3.7, Ottawa 3.9, Calgary 4.4, Vancouver 3.1, Edmonton 4.0, Winnipeg 4.2, Yellowknife 3.4, Whitehorse 3.0, Halifax 3.7. Default 3.6 covers most southern off-grid territory.
  3. Days of autonomy — 3 days for southern Canada; 4 days for Yukon, NWT, northern BC. Always pair with a generator backup.
  4. Battery chemistry — LiFePO₄ (Discover AES, BYD, Pylontech, Simpliphi, EG4) is now standard for new Canadian off-grid builds. Cold-rated lithium (Discover AES, Polar Power) is essential anywhere with unheated battery rooms — standard LiFePO₄ refuses to charge below 0°C. AGM (Rolls Battery Engineering, manufactured in Springhill NS) remains popular in budget Atlantic Canada and remote northern installs because it tolerates -40°C.
  5. Peak instantaneous load (W) — Canadian off-grid suspects: well pump 1,500-3,000 W, electric kettle 1,500 W, microwave 1,200 W, baseboard heaters (avoid!) 1,000-2,000 W, table saw 1,800 W. Most run a 5-8 kW Schneider/Magnum continuous inverter.

How the math works

The Canadian calculator follows methodology in NRCan’s RETScreen Clean Energy Project Analysis Software and CSA C22.1 Section 64 (Renewable Energy Systems):

PV array (kW DC):

kW = daily_kWh / (peak_sun_hours × derate)

Derate 0.77 covers inverter losses, MPPT charge-controller losses, DC cable losses, snow/soiling losses, and module mismatch. Canadian winter snow soiling is significant — RETScreen recommends an additional 5-10% derate Dec-Mar in snow-belt regions, but the annual figure averages out to 0.75-0.78. With Canadian defaults of 9 kWh/day at 3.6 PSH: kW = 9 / (3.6 × 0.77) = 3.25 kW DC, typically 8× 415 W panels (Heliene Mountain Iron MN/Sault Ste. Marie ON, Canadian Solar, Trina).

Battery bank (kWh nameplate):

usable_kWh    = daily_kWh × autonomy_days
nameplate_kWh = usable_kWh / (DoD × battery_round_trip_eff)

9 kWh × 3 days = 27 kWh usable; nameplate = 27 / (0.90 × 0.95) = 31.6 kWh of LiFePO₄. Maps to about 6× Discover AES 6.65 kWh or 7× Pylontech US5000.

Inverter (kW continuous):

kW = peak_load_W × 1.25 / 1000

A 3,500 W well-pump start plus 800 W background = 4,300 W × 1.25 = 5.4 kW. The Schneider Conext SW 6048, Magnum MS4448-PAE, or Outback Radian GS7048E are standard Canadian answers.

What an off-grid system actually costs in Canada (Q1 2026)

Pulling installed-cost ranges from licensed Canadian off-grid installers (Solacity Ottawa, Powerland Winnipeg, Conservation Construction Vancouver Island, Polar Power Whitehorse). Prices in CAD:

System sizePV kWBattery kWhTotal installedAfter Greener Homes Loan
Cabin / cottage2-314-20 (Li)C$18,000-26,0000% APR financed
Small full-time off-grid (9 kWh/day)3-524-35 (Li)C$32,000-45,000C$40k loan covers most
Full off-grid house (15 kWh/day)6-840-60 (Li)C$50,000-70,000+ C$10-30k cash
Northern Canadian off-grid (Yukon/NWT)8-1260-90 (Li)C$70,000-110,000+ AEA / Yukon GEF

Add C$4,500-9,000 for a Champion, Honda EU7000is, or Generac iQ propane/diesel generator. Generator backup is mandatory at all Canadian latitudes for full-time off-grid; the only debate is dual-fuel vs single-fuel.

Where most Canadian off-grid systems get under-sized

Three common mistakes from Solacity and Polar Power post-mortems:

  1. Annual PSH used in winter analysis. December PSH in southern Ontario runs 1.6-1.8 vs the 3.7 annual average — production drops to 45% of yearly mean. A bank sized to annual PSH will run flat by mid-January. Recompute at December PSH for any Canadian off-grid build.
  2. Standard LiFePO₄ in unheated battery rooms. LiFePO₄ refuses to accept charge below 0°C and self-heating circuits draw battery power constantly. Spec cold-rated cells (Discover AES, Polar Power) or build a heated battery enclosure (200-300 W inline). NRCan’s Cold Climate Battery Guide covers the trade-offs.
  3. Snow load on panels. Flat-roof or low-tilt PV in Quebec, NB, and northern BC accumulates 30-50 cm snow that blocks production for 1-3 weeks at a time. Mount at ≥40° tilt (closer to latitude) so snow sheds; budget for monthly clearing.

Pair this with the battery bank calculator, charge-time calculator, and wire-size calculator

This Canadian off-grid calculator gives the three headline numbers (PV kW, bank kWh, inverter kW). The battery bank calculator drills into Ah at 24 V or 48 V. The charge-time calculator validates recovery after a 3-day overcast/snow stretch. The wire-size calculator picks CSA C22.1-compliant AWG for the DC runs from PV to charge controller, charge controller to bank, and bank to inverter.

Sources

Frequently asked questions

How much solar do I need to live off-grid in Canada?
For a typical Canadian off-grid property running 9 kWh/day at 3.6 peak sun hours (NRCan southern Ontario annual average), you need about 3.2 kW of PV plus 24-32 kWh of LiFePO₄ battery for three days of autonomy. A full off-grid house at the NRCan residential average of 30 kWh/day (electric heat included) is essentially impossible without aggressive load shedding — most Canadian off-grid homes use wood, propane, or oil for primary heat and reserve PV for 8-15 kWh/day of small loads. Yukon, NWT, and northern BC need 4-5 days autonomy due to short December daylight.
Does the Canada Greener Homes Grant cover off-grid systems?
The original Canada Greener Homes Grant closed in 2024. The Canada Greener Homes Loan (interest-free up to C$40,000 over 10 years) remains active for primary residences and DOES cover off-grid PV and battery storage when prescribed by an energy advisor. Provincial programs vary widely: Nova Scotia SolarHomes ($0.30/W), PEI Solar Electric Rebate Program (up to $10,000), Yukon Good Energy ($800/kW), and NWT AEA Energy Action Program ($/kW varies). Always check current provincial program status — they cycle annually.
Why does Canada need so much more battery than warmer climates?
Three reasons: short December daylight (Whitehorse gets 5h 30m of daylight vs Vancouver's 8h 12m on Dec 21), heavier cyclonic cloud cover east of the Rockies in winter, and snow accumulation on panels reducing winter PV output by another 15-30% even when cleaned monthly. NRCan's CanmetENERGY recommends 3-day autonomy as the minimum for southern off-grid (south of 50° N), 4 days from 50-58° N, and 5 days north of 58° N. The CSA C22.1 (Canadian Electrical Code) Section 64 covers PV system installation requirements.
What does an off-grid system actually cost in Canada (2026)?
Q1 2026 ranges from licensed Canadian off-grid installers (Solacity Ontario, Powerland Manitoba, Conservation Construction BC, Polar Solar Yukon): a 4 kW + 25 kWh LiFePO₄ + 6 kW Schneider Conext SW or Magnum MS-PAE inverter system runs C$32,000-42,000 installed. A full off-grid house (8 kW + 50 kWh + 8 kW inverter) sits at C$60,000-80,000. The Greener Homes Loan can finance up to C$40,000 of that interest-free over 10 years, making cash flow workable even at high northern latitudes. Add C$4,000-9,000 for a propane or diesel generator backup.
Should I use 24 V or 48 V for a Canadian off-grid system?
Use 48 V for any system 3 kW or larger. Higher DC voltage means smaller wire (lower amperage at the same power), which matters in Canada where DC runs from rooftop PV to the equipment room are typically 15-30 m. The Magnum Energy MS-PAE 4448, Schneider Conext SW 4048, and Outback Radian 8048A all run at 48 V and dominate the Canadian residential off-grid market. CSA C22.1 Section 64.060 limits residential PV to 1500 V on the array side; 48 V battery is universally accepted under Section 64.400.

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