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Calculating Solar Costs
February 22, 2012 4:40 pm
In our last segment, I began exploring how to size your home up to install solar electrical generating panels. Picking up from there, the folks from residentialsolarpanels.org suggest you calculate up-front costs vs. the long-term savings you could enjoy.
For nearly everyone, the upfront cost of a photovoltaic solar system will be a major factor. However, with the yearly utility savings and the government incentives, it can be well worth the initial investment.
Considering a single solar panel can generate 21.294 kWh/month, if your electricity company charges an average of 20 cents per kWh, you would save about $512 per year. If that system costs $20,000, solar Government rebates / Tax Credits could cut that cost as much as 50 percent, so you’ll have to pay back $10,000.
That means it will take you about 19.5 years for 10 x 2 m² solar panels to pay off the system and begin truly saving. And if you consume 1,000 Kw /Month it will reduce your typical energy bill by about half.
Finally, if all the numbers work out— it's time to plan your photovoltaic system placement. A good rule of thumb to use when determining the correct tilt of solar panels is to find out the approximate latitude of your area and set the panels at an angle equal to that latitude.
This should maximize the amount of solar radiation absorbed all year. If the southward facing roof on which the panels will be installed is slanted beyond the angle of your area’s latitude, then the panels should be lifted at the bottom edges, in order to achieve the best radiation angle, whenever possible.
For flat roofs, any of the four sides can be elevated to match the latitude angle.
Finally, to start a power purchase agreement with your local utility, you will have to start filling out paperwork to get approved. One of the first things that you will have to submit is your current electric bills.
This is to show what your normal consumption is. If you get approved, you could get some solar renewable energy credits for every megawatt hour you are producing.
If your state offers money for these credits, it could add up to some nice pay for you, according to the folks at residentialsolarpanels.org.
For nearly everyone, the upfront cost of a photovoltaic solar system will be a major factor. However, with the yearly utility savings and the government incentives, it can be well worth the initial investment.
Considering a single solar panel can generate 21.294 kWh/month, if your electricity company charges an average of 20 cents per kWh, you would save about $512 per year. If that system costs $20,000, solar Government rebates / Tax Credits could cut that cost as much as 50 percent, so you’ll have to pay back $10,000.
That means it will take you about 19.5 years for 10 x 2 m² solar panels to pay off the system and begin truly saving. And if you consume 1,000 Kw /Month it will reduce your typical energy bill by about half.
Finally, if all the numbers work out— it's time to plan your photovoltaic system placement. A good rule of thumb to use when determining the correct tilt of solar panels is to find out the approximate latitude of your area and set the panels at an angle equal to that latitude.
This should maximize the amount of solar radiation absorbed all year. If the southward facing roof on which the panels will be installed is slanted beyond the angle of your area’s latitude, then the panels should be lifted at the bottom edges, in order to achieve the best radiation angle, whenever possible.
For flat roofs, any of the four sides can be elevated to match the latitude angle.
Finally, to start a power purchase agreement with your local utility, you will have to start filling out paperwork to get approved. One of the first things that you will have to submit is your current electric bills.
This is to show what your normal consumption is. If you get approved, you could get some solar renewable energy credits for every megawatt hour you are producing.
If your state offers money for these credits, it could add up to some nice pay for you, according to the folks at residentialsolarpanels.org.

