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The Cost of Solar Energy
Calculating The Cost of Solar Energy
There are many households that are interested in installing solar energy in their own homes, but they don't know how much it will cost them.
Below are some simple steps for you to determine the estimated cost of solar energy to power your home. Make sure you have your calculator with you to aid you in the computation.
Refer to your previous electricity bill and find the average of your daily power consumption in kilowatt hours (kWh/day). Your bill can help you identify it. If your bill is below $100 per month, you might be consuming less than 30kWh/day. On the other hand if your electricity bill is almost $200, maybe your daily consumption will average 60kWh/day. In the same way, your bill will tell you your monthly consumption of kilowatt hours. Divide this value by 30 and you will get your kWh/day. For instance, its 1000kWh/month, divided it by 30 would equal to 33kWh/day.
Find a US Solar Map (or other country) and determine the number of hours per day that the sun is shining on your house. It is located on the left part of the map. For example, if you are living in California, it's about 5 hours, in South California, it is 5.5 hours and in North California, its closer to 4.5 hours.
Decide for yourself how much of your total electricity bill do you want your solar array to cover? Is it 50%, 70% or 100%? If you have a strong budget, then 70% to 100% is good, but try to realize that you are just about to start using solar energy, which means that you will need to use your usual electricity for some time. On the other hand, if you have a tight budget, then start with the 50% and leaver a space for expansion in later time.
Calculate your array size in kW. The formula is:
For instance, your electricity bill is $110 per month and your daily consumption is about 30kWh/day. You are situated in Southern California and wanted to cover only 75% of your bill.
The efficiency value of 75% because of there is efficiency losses such as the irradiation, temperature, dust and wiring that can interfere to the system power performance.
After knowing the size of the solar array to be used in kW, the cost of the solar array will then be approximately estimated. The average installation cost varies among different location but the recent average is about $8 per watt for a common residential system of less than 10kW. To convert watts to kilowatts, multiply your array size by 1,000. Then, multiply it with the current estimated average which is $8/watt. The formula then is:
So, for the example above, if you have 5.45kW x 1,000w/kW x $8/watt = $43,636
$43,636 is not the exact cost of solar energy that you need to pay. Find for website that will tell you the solar incentive programs intended for your State. One of the popular website is www.dsireusa.org and locate your State to find out what they can offer you. Finally, subtract your State's discount to the total price to determine how much you needed to pay
