Wanna know how to choose the best solar panels? It’s simple: find out which ones give you the most electricity for the cheapest price. Let’s call this ‘solar value’.
Well, how do you figure out which panels give you the most electricity? Do I need to know which panels are the ‘most efficient’? Nope. Efficiency is not the same as output. Efficiency is output per area. You should only care about output. Let your installer worry about the area. Read the rest of this entry »
So, you’ve got a few quotes from solar installers and want to know which solar power system will give you more energy / output / electricity. Let me teach you how to calculate solar output like the pro’s. This way you can double-check their quotes to know you’re getting a good deal.
Step 1: Grab your solar quotes and look for the specific solar module name and how many solar modules will be installed. Make sure you know the exact panel. Circle the panels and how many. Ex. 20 x SunPower SPR-200-BLK-U.
Then find the exact solar inverter in the estimate. This might be SMA SunnyBoy, Xantrax, Fronius, or Enphase. Circle this too. Ex. SMA SB4000US (240V).
Step 1: Determine your solar array size in kW and enter it into the calculator below.
Step 2: Decide which solar panels you want to use, and enter the DC Watt rating of the specific solar panel model you want to use into the calculator below.
Example: Suntech STP210-18/Ub-1 are rated at 210 DC Watts. Sunpower 230-WHT are rated 230 DC Watts. Read the rest of this entry »
Should I use Sanyo 200′s or Suntech 270′s? SunPower 210′s or Canadian Solar 240′s? Which size solar panel you use depends mainly on how much roof space you have available and how much electricity you plan to use (with solar power). Below are 6 steps to calculate which size solar panels you need for your building.
Step 1: Know Your Electricity Usage
Gather your old electricity bills for the past 12 months. Contact your utility company if you don’t have them and your electricity provider should gladly send you a printout with your past electricity usage. You’re looking for 2 things: (1) your monthly kW/h usage, and (2) your monthly cost.
Step 2: Know your Roof Direction
Grab a compass (maybe your car navigation, or check Google Maps) and figure out which way is South. Go outside, look at your roof and see how much roof space is facing South, Southwest, East and West. The more South the better, but West is actually okay.
Disclaimer: Our solar calculators estimate the solar cost and size of a solar project. These should only be used as rough estimates, and may be incomplete. A solar installer would be able to provide you with a more accurate estimate.
(*Calculator at bottom)
