Preface. Although you may not be as far north as Victoria, British Columbia (48.4 latitude), you’d ideally want to be at 30 degrees or less latitude from the equator to even consider the expense of off-grid solar power. And even then you’ll need to be wealthy. Keep in mind that the Tesla Powerwall 2 is $5,500 for the battery alone, plus about $1500 additional charges for installation and other components.
If you’re getting solar for when TSHTF, you’d better have a lot of spare parts and enough mechanical bent to fix the system yourself until the batteries die…
— Alice Friedemann www.energyskeptic.com author of “When Trucks Stop Running: Energy and the Future of Transportation”, 2015, Springer and “Crunch! Whole Grain Artisan Chips and Crackers”. Podcasts: Derrick Jensen, Practical Prepping, KunstlerCast 253, KunstlerCast278, Peak Prosperity , XX2 report
November 23, 2017. Want to go off-grid? You might need hundreds of Tesla batteries.The Climate Examiner, Pacific Institute for Climate Solutions.
Going completely off-grid is infeasible for most households in Western Canada, energy systems modellers conclude, due to the diminished amount of sun in our northern latitude. To “cut the cables” to the electricity grid, requires an impractical number of batteries or solar panels.
- The scenarios below do not account for electricity needs to heat homes or charge electric vehicles
- Fewer solar panels = you need more batteries
- Fewer batteries = you need more solar panels
Families in BC use solar panels on their roof and install batteries in their garage because they want to reduce electricity costs or do their part to help reduce emissions. Some have dreams of one day going entirely off-grid. So researchers with the Pacific Institute for Climate Solutions’ 2060 energy future pathways project modeled just how feasible this would be.
They used 2016 data from a typical three-bedroom house in Victoria with an annual load—or average electricity demand—of 9,600 kilowatt hour (kWh). The house uses natural gas for its heating and a conventional gasoline vehicle, meaning no extra load from these sources.
A common PV system is 12 kilowatts (kW) as a larger PV system requires more roof. Researchers found that given Victoria’s solar irradiance, a 12 kW PV system needs a 1,766 kWh battery to achieve self-sufficiency. This is equivalent to 131 Tesla Powerwalls.
Another option is to reduce the size of battery and buy a larger PV system, as more energy is available and thus less needs to be stored. If a homeowner bought a 30-kW PV system, they could get away with a 289 kWh battery (equivalent to 21 Powerwalls). But this PV system would require an area of roughly 300 square meters (3,200 square feet)—about the size of a tennis court.
They ran the numbers for Vancouver, Kelowna and Calgary. The results for Vancouver and Kelowna similar to Victoria. But Calgary, with its clearer winters, required less PV and battery capacity to be self-sufficient. Calgarians could make do with a 9 kW PV system and about 62 Powerwalls. With a 30 kW PV system, taking up 240 m2 (2,475 square feet), the homeowner needs roughly 10 Powerwalls.
But in these clear, cold places, the electricity demand of the household rises due to the electrification of heating and transport so the prospect of self-sufficiency is even further out of reach. The researchers found that the increase in demand from heating via electric baseboards at least a 22 kW PV system and 236 Powerwalls. Newer technologies, such as heat pumps would have a reduced impact on electricity demand.
The projections for the number of batteries seem mind-boggling, but they are in line with storage requirement assessments for other jurisdictions.