How To Calculate Your Off Grid Needs

The biggest struggle most have with going off-grid is knowing just how much equipment they need in order to take on such a task. How much electricity does one family or one person need? Asking and answering that question is the single biggest step to even considering your solar needs. If you don't need much you may drown yourself in equipment and cost. If you need too much you may actually size yourself out of a tiny house due to equipment and setup. It is time to do the math and take inventory of your life and power consumption. 

If you have the benefit of living on the grid for some time you may have a reasonable idea of how much electricity you use each month. You have your power bill or electrical company statement to compare and average your kWh reading. Go ahead. Take a look! You can just divide your average monthly bill by 30 and pretty much understand your daily needs. If you are still in planning phase though and don't have the history from an electrical company, here's a good way to plan:

Everything that runs on electricity has a "load". To find out how much power you need, make a lit of all your loads, and multiply their power requirements by how many hours you think you'll use them in a day. For example, your mini-split HVAC may be used 8 hours a day. In comparison your flat iron may only be used for .6 hours a day. Here’s the math:

  • Make a list of each appliance, power tool, and lightbulb you need.
  • Look at the manual, label, or search the Internet to find the power they need to run, (measured in Watts)
  • Multiply the wattage of each appliance by the number of hours you need it.

Some appliances like refrigerators are plugged in all day but only draw power when a compressor clicks on. Below is a pretty common power usage idea.

APPLIANCE WATTAGE HOURS/DAY WATT-HOURS/DAY: Coffee Maker 600 0.5 300 Electric Hot Plate 1,650 1 1,650 Fan (floor) 40 4 160 Hair Dryer (1600 watts) 1,800 0.5 900 Laptop computer or device 225 4 900 Lightbulb – 14W LED 14 4 56 Microwave Oven (650 watts) 1,000 0.5 500 Mini-Split Ductless HVAC 800 5 4,000 Radiant Heater 1,300 4 5,200 Refrigerator – 17 cu ft 180 6 1,080 WiFi Receiver 250 2 500 Slow Cooker 220 3 660 Television – Flat Screen 120 2 240 XBOX 360 100 2 200

All of these calculations can be done on paper or even in a spreadsheet. However, you may want to find a solar calculator app like this one or one of the dozens online! 

Again, this is only the first step in four to building out your solar system. It is arguably the most important though and certainly one that all tiny housers need to pay attention to. 

So have you started your solar construction? Do you know what your solar needs are? If not, what is holding you back? The sheer size of tiny houses on wheels makes them ideal for off-grid living. Let us know in the comment section below. To continue the conversation and more like it, join us on Facebook or follow us on Instagram!

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