Grid-tied solar

[dave1949]

The reason that the product is warrantied for 20 years is because after that many years of baking in the sun, it's no longer reliable and/or the power output from it is no longer at a level that makes it useful. PV cells are electrical components, and each heat / cool cycle and "power up" (getting hit with the sun in the morning) cycle causes wear.

When the solar system providers can show me that 90+% of the equipment they installed over 20 years ago is still in use, I'll be at a point where I can consider making the investment.

I have no idea how long the system will perform at a reasonable level, but it seems likely that something sitting outside in the sun for 20 years is going to show it.

Since I am 63 years old, my personal performance and payback horizon- well, I'll give it 10-15 years :laughing: I will likely either be gone in 20 years or unable to spell "solar." I am not expecting miracles. The system is off to a decent start but as I explained to Dan, if the cost of the money tied up in it is included, I think it will have to repay it's purchase price in 10-12 years and perform decently well for another 8-10 years to really break even.

If the price of electricity goes up in relation to an average annual rate of inflation around 2.5%, then my rates would go from 14 cents now to about 18 cents per kWh 10 years from now. That rate of increase is greater than the expected rate of performance decrease (~1%/yr). The system generates fewer kW, but each is worth 4 cents more than 10 years ago.

The numbers are close enough I don't think I am just throwing money away, yes there would be less risk just letting it earn interest or something. My primary goal is to eliminate what I consider to be a poor use of propane, just for the sake of reducing fossil fuel use. We all have our causes.

 

[yelbike]

When the solar system providers can show me that 90+% of the equipment they installed over 20 years ago is still in use, I'll be at a point where I can consider making the investment.

Good for you.....don't buy a solar system, nobody is trying to sell you one. If it works for the op all the better for him.

 

[Travelover]

Good for you.....don't buy a solar system, nobody is trying to sell you one. If it works for the op all the better for him.

Exactly what I was thinking.

 

[Redneck in training]

Just today I talked to an expert. I attended alternative energy presentation at Iowa state Fair. The presenter was a researcher from Iowa State university.
In his words we are in "perfect storm" condition.
1.) China put on line the world larges silicon wafer plant.
2.) World economy is in depression.
3.) Many countries (large installers of the solar) either cut or completely canceled subsidy so demand for solar panels dropped.
4.) China started producing solar panels in mass numbers and flooding the world marked depressing cost/watt to unprecedented level and bankrupting quite few manufacturers in USA and Europe in the process.

Certified panels run around $1.2/watt while off brand panels are as low as 70 cents/watt.
Cost of hardware (framework, panels, cables, inverters etc) dropped to about $1.65/watt. Total installed cost (got a ball park quote today) is about $3.9/watt.
State of Iowa doesn't require certified installer to do the work. It requires state inspection only.
State of Iowa gives a zero percent loan for half of the cost of the project.
US government gives 30% tax write off for the cost of the project. Still don't know if own installation work can be added to the final cost of the project. Most likely not.
Here is an example:
My property needs about 20 kW system costing about 40000 in hardware only. To get the 20K zero percent I would have to borrow 40K from a bank at about 6% on half of the amount.
My current electric bill is about 300/month. If the solar covers my consumption it will drop to about 30/month. So if the loan payment is about 270/month for 15 years loan, I will be paying about the same amount as for electricity. The loan payment will not go up while elctricity cost will. I will also get 12000 federal tax write off.
I think if you can install solar by yourself it is no brainer at current cost (while it lasts).
Guys what do you think? Shoot some holes in my thinking.
Sorry for hijacking the post. If I actually do the project I will start new post.

 

[Alien]

You guys have it so good with your energy costs. We get hit 23 cents Kwh and and can't fathom why. I believe it is something to do with greed. Naturally I have a 4 Kwh system to alleviate the pain.

 

[Redneck in training]

You guys have it so good with your energy costs. We get hit 23 cents kWh and and can't fathom why. I believe it is something to do with greed. Naturally I have a 4 kWh system to alleviate the pain.

It is cost of large infrastructure spread over small number of people. I think it is partially related to population density.

 

[yelbike]

It is cost of large infrastructure spread over small number of people. I think it is partially related to population density.

I don't know how true that is. I live in Manitoba, home of the hydro electric damns. Most of our power is produced some 800 km away in north, huge transmission and distribution costs. They have quite a few new projects on the go. I think the biggest difference is deregulation in your area. Our power is government owned and regulated. We pay only about 5.2 per kwh. Our whole population is only 1.5 million I think.

I think the super high prices reflect corporate greed more than anything else. Imho

 

[whirly]

You guys have it so good with your energy costs. We get hit 23 cents Kwh and and can't fathom why. I believe it is something to do with greed. Naturally I have a 4 Kwh system to alleviate the pain.

The more you have to pay per kWh the better solar looks. I'm on a small island in the middle of the pacific, 19° above the equator, and ALL of our fuel has to be shipped in. Consequently, our electricity cost is 39¢/kWh. The upside, besides I don't need heating, is my payback on a solar system would be around 5 years on pretty much any size system. On the flip side, Nanook of the North at latitude 50 with hydro or local LNG and rates close to zero wouldn't see much need or use for solar.

Makes sense for me, not for Nanook.

 

[Loren49]

The reason that the product is warrantied for 20 years is because after that many years of baking in the sun, it's no longer reliable and/or the power output from it is no longer at a level that makes it useful. PV cells are electrical components, and each heat / cool cycle and "power up" (getting hit with the sun in the morning) cycle causes wear.

When the solar system providers can show me that 90+% of the equipment they installed over 20 years ago is still in use, I'll be at a point where I can consider making the investment.

Your conclusion is flawed. The warranty is that the output will remain at or above 80% for 20 years. After 20 years it may remain there for a long time but would more likely continue to decline at a similar rate. It is warranted to not lose more than 1% per year. So its possible that at 50 years it would still produce over 50%. At that point it would have been paid for for 30 to 35 years and its production at any level would seem to be a good thing. Does anyone consider something useless after the warranty expires?

A couple of my panels are still producing at useful levels after more than 20 years and a few others doing well after 15. The surface of the panel chalks a bit over time and loses its transparency so production decreases. Mechanical generators have more serious issues over 20 years.

Loren

 

[meburdick]

Your conclusion is flawed. The warranty is that the output will remain at or above 80% for 20 years. After 20 years it may remain there for a long time but would more likely continue to decline at a similar rate. It is warranted to not lose more than 1% per year. So its possible that at 50 years it would still produce over 50%. At that point it would have been paid for for 30 to 35 years and its production at any level would seem to be a good thing. Does anyone consider something useless after the warranty expires?

A couple of my panels are still producing at useful levels after more than 20 years and a few others doing well after 15. The surface of the panel chalks a bit over time and loses its transparency so production decreases. Mechanical generators have more serious issues over 20 years.

Loren

How is my conclusion flawed? I stated exactly what you stayed with regard to what is warranties. And, for what it's worth, the panels are not guaranteed to lose no more than 1% efficiency pet year. 100% of all panels produced have an efficiency of less than 100%. Losing 1% per year for 20 years would leave the panel at less than warranties levels prior to the end of the warranty.

A "couple" of your panels? How many panels do you currently have that are 20+ years old? How many that are that age are not producing at levels at or above 80%. How many panels at least that old are producing at below 80% our have already been replaced?