diy solar

diy solar

How much power do I need?


Works in theory! Practice? That's something else
Sep 20, 2019
Key Largo
Sweet! You've decided to install some solar panels! So, where to begin?

The first thing to do is to determine how much you power you need. Power is measured in "watts", for example on the back of your device you might see a label saying it takes 60 watts. By itself, that number is only so useful, you need to also know how long you use the device for. Say you have a 60 watt light bulb. If it's on for an hour it'll consume 60 "watt hours"; or abbreviated as "wh". 1000 watt hours is a kilowatt hour, and typically abbreviated "kWh".

If you're trying to power the life-style in your house, most people can just look at their power bills and determine how many kWh per day they use, it'll vary throughout the year depending on how much seasonal power you're using for air conditioning or heating.

But sometimes you just want to power a few devices, or want to add power where you haven't had it previously. This link will take you to the wiki where it'll walk you through the steps to perform an energy audit. Basically you figure out how much power a device consumes, how long you use it, and then add it all together.

Getting the amount of power for some devices can be tricky. If you can't get it off the internet, you can always measure it with a meter like the one shown to the right.

Basically you plug the meter into the outlet, then plug your device into the meter and use your device as you normally would. That'll tell you how long you used a device (e.g., TV) and how much power it consumed. Repeat that for every device and jot down the watt-hours it consumes. Then add them all together and that's the power you need. Some devices like TV's will consistently draw the same amount of power. Other devices like computers will vary depending on what you're doing. The best way to know is leave the meter on for a few days and go about your normal life. Some devices like refrigerators hum along nicely, then suddenly start gobbling power (i.e., the refrigerator enters defrost mode).

You can also measure the amount of power devices consume, and use that to make informed decisions when buying consumer devicers. Most people are aware at how much power you can save by simple things like converting incandescent bulbs to LED bulbs. For example, a 40 watt light bulb that's on all the time, is consuming a 1000 wh per day. An LED bulb twice as bright would only consume 150 wh/day. But, not all LEDs are equal, beware really cheap ones as they can cause problems with wifi.

Doesn't sound like much. But 10 watts a day, 24 hours a day, at 15 cents per kWh is 10 x 24 x 365 x 0.15 / 1000 = $13.14.

A lot of devices, like TVs, internet modems, clocks, are all either on all the time or are consuming stand-by power. It adds up.

For more tips, google Reducing Energy Consumption.
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diy solar

diy solar