Off Grid Electricity

Solar SunriseWhen we were shopping for the ideal property to build our homestead on, I assumed it would probably have grid electricity already installed. At that time, (2010 – 2011) the math argued for staying on the grid, and perhaps installing some solar under a net metering program. This would not be energy independence, as these systems tend not to be usable during an outage. The main advantage was that you would not need to buy, maintain and replace batteries. The experts said that at best, a solar installation would help reduce your home energy costs over time. The property we found in the fall of 2011 had grid electricity available at the lot line. The quotes we got for installation made us re-think the idea of going totally independent. We reasoned that the 25k saved on a grid installation would buy a lot of panels and batteries. My simplistic calculations at the time estimated that over 20 years, the grid option would cost about 75k, whereas fully independent off grid should not exceed 50k. The advantages of full energy independence are still evident, uncertainties about the cost and security of grid supplied energy have not receded. The ecological considerations are important to us, but are generally not allowed to overule the practical and economic. The good news is that it seems to be getting easier to reconcile ecology to economy.
Power System 2013 During the earliest days of establishing a presence here on the land in 2013, all electrical power came directly from a gas powered generator. After we moved from the west coast into a rental in town (14km from the property) I set up the first storage and inverter system. During the early stages, my efforts depended heavily on elderly components left over from my first off-grid experience more than a decade ago. Over the winter of 2013-14, I commuted to the property every day warmer than about -25c. The simple system that consisted of two 6 volt golf cart batteries, a 45 amp charger and a 1500watt inverter was adequate to provide lights, a fan and to run small power tools.
After we moved on to the homestead full time at the end of April 2014, a major upgrade was needed. Our original plan to run my RV type fridge on propane ran into a snag when the propane control burned out after a couple of weeks use. The fridge could also be run on 110volt, but was hideously inefficient, drawing an average of 350watts. Late in the season we replaced that fridge with a smaller 4.3 cu. Ft. bar fridge with a modest 65watt draw. Our initial solar capacity consisted of two ancient 75watt panels, plus a 100watt panel acquired from a big box store the year before. After some hunting around we found a good supplier in Regina, who provided 2 additional panels of 150watts each. A problem at that point was that the combined solar capacity was enough to overwhelm one of my old 20amp charge controllers. So, I split the system into two battery banks, each with it’s own charger, inverter, charge controller and solar panels. This setup made best use of the components I had on hand, gave some redundancy in case of component failure and allowed me to delay expensive upgrades. Power System 2014
The setup as it exists in the winter of 2014-15 is working reasonably well, but still requires a fair bit of generator run time. Long term plans call for a much bigger array of panels, the deployment of the small wind generator that we have on hand, a possible upgrade to a larger wind generator, a 4000watt true sine inverter/ charger, an mppt charge controller to reconcile older and newer solar panels and a much bigger battery bank. (whew!)
We will continue to learn as we go, but our confidence level in being able to live off-grid with acceptable levels of comfort, convenience, security and economy is on the rise.

SYSTEM SPECIFICATIONS as of January 2015

Solar Capacity: 550watts @12volts
Wind Capacity: n/a
Generator Capacity: Main – 6500watts
Backup – 2000watts

Battery storage: 900amp hours @12volt
Inverter Capacity: 1500watt x 2

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