When the Solar Guy comes by
Posted: Sat Mar 22, 2008 7:54 pm
DAR
So a solar guy from Sun City Solar Energy came by today. They are located in Springdale. He sells a solar water heater package (and a version that can heat a swimming pool), a grid tied solar panel system and a solar powered attic vent fan.
The water heater package is about $7,200. The attic vent fan is $750 installed. We really don't use enough water to make the water heater useful. The attic fan is a little pricey. I think I can put something together for a lot less, solar or not.
The solar panel choices are a 8 panel 1.4 kw system for about $17,000 and a 12 panel 1.56 kw package for $19,800. That's total price, installed ready to go, tax paid. A $2,000 tax rebate is currently available which would come off of that total.
He claimed the panel package would pay for itself in 22-27 years. I don't see how. According to his numbers in Arkansas we can expect to get a yearly average of 5.5 hours of sunlight per day. That's not bad. This system will make, in the best sunlight 1.56kw and if it does it for 5.5 hours a day that equals about 8.58 kwh per day. Electricity currently costs about .10 cents per kwh so that's a generation of about 85 cents per day worth of electricity. That's $313 per year. If you divide that into $19,800 and don't account for interest on the value of the money, that works out to about 63 years. There are a few details that in fact make it worse than that, but close enough to seriously disqualify this as any kind of sensible financial investment. First of all, the electric company is not going to credit you at 10 cents a kwh, not even close (unless the were forced to provide such a subsidy as is done in Canada and Germany etc.).
If I were to borrow that $20,000 at 9% interest over say 15 years, the monthly payment would be $202.85. Total paid at the end of 15 years is: $36,513. Divide that by the $313 per year generated by my little electricity power plant and break even payback time is now 116 years.
At this point he tried selling the system on a hypothetical projected increase in the cost of electricity. He said electricity had doubled in cost in the last ten years and he expected it to double again in the next five. I didn't think that was right but said I would look into it. Here is what I found:
![Image](http://www.grinzo.com/energy_old/graphics_misc/aeo_prices.png)
That chart isn't referenced so it is best to go here: "Average Retail Prices of Electricity, 1960-2006." Here is the html link
So if you look at the "real" average US cost of residential electricity per kwh you get:
In 1960 = 12.4 cents
In 1970 = 8 cents
In 1980 = 10 cents
1990 = 9.6 cents
2000 = 8.2 cents
2006 = 8.96
In fact, in the last 46 years I can only find 15 years in which electricity cost less than it did in 2006. So the fellow's information is not accurate.
I wish them the best. I wish energy did cost more so as to reflect the true value and expense to the planet. I wish solar panels we a lot cheaper. Until this happens I can't say I love solar power enough to make such a terrible investment.
D.
So a solar guy from Sun City Solar Energy came by today. They are located in Springdale. He sells a solar water heater package (and a version that can heat a swimming pool), a grid tied solar panel system and a solar powered attic vent fan.
The water heater package is about $7,200. The attic vent fan is $750 installed. We really don't use enough water to make the water heater useful. The attic fan is a little pricey. I think I can put something together for a lot less, solar or not.
The solar panel choices are a 8 panel 1.4 kw system for about $17,000 and a 12 panel 1.56 kw package for $19,800. That's total price, installed ready to go, tax paid. A $2,000 tax rebate is currently available which would come off of that total.
He claimed the panel package would pay for itself in 22-27 years. I don't see how. According to his numbers in Arkansas we can expect to get a yearly average of 5.5 hours of sunlight per day. That's not bad. This system will make, in the best sunlight 1.56kw and if it does it for 5.5 hours a day that equals about 8.58 kwh per day. Electricity currently costs about .10 cents per kwh so that's a generation of about 85 cents per day worth of electricity. That's $313 per year. If you divide that into $19,800 and don't account for interest on the value of the money, that works out to about 63 years. There are a few details that in fact make it worse than that, but close enough to seriously disqualify this as any kind of sensible financial investment. First of all, the electric company is not going to credit you at 10 cents a kwh, not even close (unless the were forced to provide such a subsidy as is done in Canada and Germany etc.).
If I were to borrow that $20,000 at 9% interest over say 15 years, the monthly payment would be $202.85. Total paid at the end of 15 years is: $36,513. Divide that by the $313 per year generated by my little electricity power plant and break even payback time is now 116 years.
At this point he tried selling the system on a hypothetical projected increase in the cost of electricity. He said electricity had doubled in cost in the last ten years and he expected it to double again in the next five. I didn't think that was right but said I would look into it. Here is what I found:
![Image](http://www.grinzo.com/energy_old/graphics_misc/aeo_prices.png)
That chart isn't referenced so it is best to go here: "Average Retail Prices of Electricity, 1960-2006." Here is the html link
So if you look at the "real" average US cost of residential electricity per kwh you get:
In 1960 = 12.4 cents
In 1970 = 8 cents
In 1980 = 10 cents
1990 = 9.6 cents
2000 = 8.2 cents
2006 = 8.96
In fact, in the last 46 years I can only find 15 years in which electricity cost less than it did in 2006. So the fellow's information is not accurate.
I wish them the best. I wish energy did cost more so as to reflect the true value and expense to the planet. I wish solar panels we a lot cheaper. Until this happens I can't say I love solar power enough to make such a terrible investment.
D.