Grid-tied solar

[MossRoad]

http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/redbook/atlas/serve.cgi

It looks like we're both in the poorest solar areas in the US. Locally there are a good number of small to medium sized solar installations. My point is that even with the available construction subsidies, the only way that a profit will happen is if an adequate amount of electricity is produced. The proposed project will still require a sizable investment and its hard to believe that these investors did not require good information that it will be profitable. Also note that during the time period (October to March) of greatest cloud cover the area has it shortest daylight and the electrical demands are lower. Over the rest of the year there are the greater hours of sunshine and the higher electrical demand. In my area many installations are on roofs and are covered with snow part of the winter but over the long summer days and with a relatively flat orientation the yearly output is enough.

Loren

Link doesn't work. What was it to?

 

[MossRoad]

I was talking to a town councilman (an engineer) recently about the installation at the town buildings (not far from Lake Ontario) and he said that even on 10-15 degree overcast days, if there is a little bit of the panel peeking out from under the snow, it will clear the whole panel off.

Aaron Z

In my experience they do clear in moderate temperatures but when its -20 F its plenty slow. Many will be blown clear with a good breeze if it is was very cold when it snowed. I've had fixed mounted panels for 25+ years but adjusted them to vertical over the coldest months...very little ice or snow problem. They are fixed east/west but were hinged so I could adjust angle to sun. My current setup is fixed at an angle so I do have a bit more snow issue. I now clear them when needed with a roof scraper (not sure the right name) Actually I have gone south for 2 months the past 2 years so my good son does it!

Loren

Loren

I just pulled a foot of snow off of my roof that was taking days to melt and making icicles (its called a roof rake ). I know that our driveway is black asphalt. And if I plow it early enough on a sunny day, by days end, its melted and dry, but only of its above 15-20 degrees. Anything colder and it doesn't matter. Of course, our driveway isn't angled towards the sun, so that would help a bit, too.

I just don't see the energy savings payback at my location for solar as being acceptable VS investing in the stock market. I mean really, our electric averages about $100-120 per month for the year. So let's say $1500 for the year. How much would a solar installation that could power my home with lights, fans, and appliances in winter, pool, air conditioning, lights, and appliances in summer cost? Estimates at over $20K from people in my area. It would take 15 years just to break even. Take a $20k chunk and stuff it in the stock market and I get $40k in 7 years and $80K by year 15. I'd have only saved $22,500 in electric bills (discounting any maintenance/repairs on the system), and the system would be 5 years from end of life (based on 20 year life span). I'd be out over $57K.

 

[MossRoad]

I ran pvwatts with the same parameters as above (except I added 3 degrees of tilt) for Portland, ME. The result is 1,397.1 mwh per year compared to 1,248.8 mwh per year for South Bend, IN. That is 11.9% less in South Bend than Portland.

Portland models 10.3% higher than Waterville, ME, the location I use for my system. Modeling my system based on Waterville predicts 4.828 mwh/year which comes pretty close to my actual output of 4.984 mwh/year. The 156 kwh difference between the prediction and my actual output amounts to 7 reasonably sunny days per year. The older version of pvwatts that was used to size my system modeled at 4.447 mwh/year. The new version is more accurate but still conservative.

Running pvwatts for South Bend using my system size (4.32 dc kilowatts), standard 15% efficiency panels, 40 degree fixed-angle, roof-mounted, facing due south, the prediction is 5.326 mwh/year compared to my actual output here of 4.984 mwh/year. Using my actual 70 degree mounting angle in South Bend, the prediction is 4.542 mwh/year. Changing my system from 70 to an optimal 45 degree angle predicts 5.264 mwh/year--slightly less than if my system were in South Bend all other things being equal.

Micro-climates and perceptions aside, the numbers say South Bend (probably at the airport) is not appreciably different than my home. pvwatts is thought to be a reasonably accurate tool for solar system sizing. Unless there is something known to be wrong with the weather data or model for South Bend, or you can identify a small micro-climate effect specific to a given site, I think I would trust it.

A pv solar system functions as a very expensive insolation meter in addition to generating power. Remember there are almost infinite graduations between dark and full sun. Not all cloudy or clear days are created equal.

Thanks for running those numbers. I appreciate it and will look deeper. :thumbsup:

 

[dave1949]

I just don't see the energy savings payback at my location for solar as being acceptable VS investing in the stock market. I mean really, our electric averages about $100-120 per month for the year. So let's say $1500 for the year. How much would a solar installation that could power my home with lights, fans, and appliances in winter, pool, air conditioning, lights, and appliances in summer cost? Estimates at over $20K from people in my area. It would take 15 years just to break even. Take a $20k chunk and stuff it in the stock market and I get $40k in 7 years and $80K by year 15. I'd have only saved $22,500 in electric bills (discounting any maintenance/repairs on the system), and the system would be 5 years from end of life (based on 20 year life span). I'd be out over $57K.

I'm not trying to talk you into a solar system, but there are few issues you didn't include in the comparison.

1) The sun is more reliable than the stock market and the timing of its performance is very predictable. It shines through bull and bear markets, recessions and depressions. No one can abscond with the sunshine. It is immune to speculators and human error. Supply and demand of sunshine are immaterial.

2) You may double your money consistently for 15 years, or you may not. If you do and want the funds it going to cost you 15% in capital gains on any sale price above your basis. Plus you will likely generate taxable dividend and interest income every year. The value of the output of a solar system is not taxed but beware the possibility of personal or real property taxes levied on a residential solar system.

3) The price of electricity, especially in Indiana which is currently very reliant on coal, is likely to increase over the next 20 years. At annual inflation and price increases of 1.5% for 20 years, $1320 ($110/month) today will become $1778. 2.5% price increase plus inflation would become $2163. Unless your home becomes a lot more efficient or your demand declines, either of those two numbers is more probable than a flat $1320 for 20 years.

4) Your scenario is based on being able to pay your electric bill and invest in the stock market. I'm sure you can but that is not an apples to apples comparison to what happens to the $20,000 in an either/or choice because you have removed the burden of paying for the electricity from the invested funds. You could evaluate investing in any home energy-related project and reach the same conclusion as you did for solar pv when it's not a true either/or choice--you are choosing both of two possibilities simultaneously for the same set of funds.

 

[MossRoad]

Good points. However, in the next 10-20 years cloud cover is expected to increase in this area, as is precipitation. I believe its supposed to do that for most of northern U.S. and Canada. There are too many unpredictable events to rely on solar in this area. We are also in tornado alley. Have any studies been done on how solar panels hold up to high winds, flying debris and large hail? And energy companies are pushing to lessen and even eliminate the programs where they will buy any of your unused power because it puts undue burden on customers that don't have solar installations. How much does maintenance on the solar equipment, batteries, etc... cost? I have zero maintenance on my current electrical system. I just don't see the energy savings payback on the investment being worth it in this location.

There is a huge solar installation at the Indy airport. That is being touted as quite successful... until you pull the government and utility subsidization from the equation. The Indianapolis Light and Power Company buys the solar electricity for 3-4 times MORE than they can sell it. They compensate by raising the rates to their customers. Financially, it doesn't make logical sense. Its tree hugger voodoo economics (and I'm a tree hugger). :confused2:

 

[Loren49]

Link doesn't work. What was it to?

Not sure why it didn't work. It was a national map showing amount of solar efficiency (not correct term). I believe it showed 5 different levels and we were in the 4th. Seattle area and Alaska were in the 5th.

Loren

 

[Loren49]

Good points. However, in the next 10-20 years cloud cover is expected to increase in this area, as is precipitation. I believe its supposed to do that for most of northern U.S. and Canada. There are too many unpredictable events to rely on solar in this area. We are also in tornado alley. Have any studies been done on how solar panels hold up to high winds, flying debris and large hail? And energy companies are pushing to lessen and even eliminate the programs where they will buy any of your unused power because it puts undue burden on customers that don't have solar installations. How much does maintenance on the solar equipment, batteries, etc... cost? I have zero maintenance on my current electrical system. I just don't see the energy savings payback on the investment being worth it in this location.

There is a huge solar installation at the Indy airport. That is being touted as quite successful... until you pull the government and utility subsidization from the equation. The Indianapolis Light and Power Company buys the solar electricity for 3-4 times MORE than they can sell it. They compensate by raising the rates to their customers. Financially, it doesn't make logical sense. Its tree hugger voodoo economics (and I'm a tree hugger). :confused2:

Remember also that the viability of coal and other fossil fuel generating economics will likely change over the next 10 to 20 years. Also the hidden costs of pollution and mining may cover some of the premium now given as an incentive to renewables. I don't thing its as black and white as you conclude. Many things have been subsidized as a way of kick starting their use but that's a discussion for another place. (many existing established things are still subsidized and many hidden costs are passed on to tax payers)

All of my solar and associated material (batteries, inverters, regulators) have been purchased with no subsidies or incentives. I think you would find that many small stand alone systems were purchased in the same way. Its work quite well and I've enjoyed the independence.

Loren

 

[dave1949]

Good points. However, in the next 10-20 years cloud cover is expected to increase in this area, as is precipitation. I believe its supposed to do that for most of northern U.S. and Canada. There are too many unpredictable events to rely on solar in this area. We are also in tornado alley. Have any studies been done on how solar panels hold up to high winds, flying debris and large hail? And energy companies are pushing to lessen and even eliminate the programs where they will buy any of your unused power because it puts undue burden on customers that don't have solar installations. How much does maintenance on the solar equipment, batteries, etc... cost? I have zero maintenance on my current electrical system. I just don't see the energy savings payback on the investment being worth it in this location.

There is a huge solar installation at the Indy airport. That is being touted as quite successful... until you pull the government and utility subsidization from the equation. The Indianapolis Light and Power Company buys the solar electricity for 3-4 times MORE than they can sell it. They compensate by raising the rates to their customers. Financially, it doesn't make logical sense. Its tree hugger voodoo economics (and I'm a tree hugger). :confused2:

A solar system would be covered for those Act of God perils under a typical homeowner's insurance policy. Stock market investments are not insured or insurable. The value (principle) of an investment is exposed to much higher risk in the stock market.

Yes, utility revenue streams are beginning to be and will continue to be upset by local generation. Their operating income plan is not designed to accommodate that. Who knows how that will play out over time? For certain, the utilities' backs are against the wall a bit on the issue. The more local generation eats into their revenue, the more they need to raise their rates or move to peak usage billing--which encourages more local generation.

To me the important financial question is how can carbon-related emissions be reduced without putting us in the poor house? I see carbon footprint reduction as an over-arching imperative that we aren't going to avoid. As I showed in my post #752 about my personal returns on solar pv, I can achieve that at no cost; actually I can earn a little while achieving that goal without being subsidized. That is a reasonable outcome; I'm not making a pile of money but it's not costing me anything to reach a goal either. I see this as a "pay me now or pay me later" scenario when "later" is going to be more expensive.

 

[fordmantpw]

Have any studies been done on how solar panels hold up to high winds, flying debris and large hail?

From the testing reports I have seen, they stand up better than the shingles on the roof.

In reality, what does it matter? If you have significant storms, it will be a claim on your homeowner's insurance, and the solar panels will be repaired/replaced as necessary based on the policy. I've checked with my agent and there is not additional fee, solar panels are included as if they were part of the house.

 

[Loren49]

Here is an interesting analysis.

Report: Solar Is Cheaper Than the Grid in 42 of the 50 Largest US Cities : Greentech Media

Loren

 

[Loren49]

Here is an interesting analysis.

Report: Solar Is Cheaper Than the Grid in 42 of the 50 Largest US Cities : Greentech Media

Loren

 

[houstonscott]

Here is an interesting analysis. Report: Solar Is Cheaper Than the Grid in 42 of the 50 Largest US Cities : Greentech Media Loren

You know, Loren, on any other subject you yourself would never tolerate such a study and poo-poo it as nothing more then propaganda. The study conducted by the very people involved with green energy. What if I showed you a study declaring NG cheaper than solar, funded and conducted by NG industry. HS

 

[Loren49]

You know, Loren, on any other subject you yourself would never tolerate such a study and poo-poo it as nothing more then propaganda. The study conducted by the very people involved with green energy. What if I showed you a study declaring NG cheaper than solar, funded and conducted by NG industry. HS

HS
You're welcome to post that study and I'll look at it and see how they came up with the numbers. Did you read what I referenced before you criticized it? They calculated using the subsidies available in each area and projected output along with the cost of capital. What is the problem? Maybe it actually pays...many seem to feel it does as a good deal of solar is being installed.

This is the source:
NC Clean Energy Technology Center - Advancing Clean Energy for a Sustainable Economy
NORTH CAROLINA

Clean Energy Technology Center

Address:
1575 Varsity Drive
North Carolina State University
Raleigh, NC 27606

Mailing Address:
Campus Box 7409
North Carolina State University
Raleigh, NC 27695

nccleantech@ncsu.edu



----I'm not going to wait for the NG company to publish a study showing that for the individual homeowner it makes good financial sense... I don't think I have enough time left on earth for that! :thumbsup:

Loren

PS - As I'm sure you noticed (sorry for the sarcasm) One of the Photos on their website is a truck with "this truck runs on clean natural gas" painted on its side.

This s what they do:
What We Do

The N.C. Clean Energy Technology Center, at N.C. State University, advances a sustainable energy economy by educating, demonstrating and providing support for clean energy technologies, practices, and policies.

The N.C. Clean Energy Technology Center serves as a resource for innovative, clean energy technologies through demonstration, technical assistance, outreach and training. It also administers the Database of Incentives for Renewables & Efficiency (DSIRE), a resource providing financial incentives and policies.

 

[John Dougherty]

Good luck! I put a Solar edge system in nine months ago (10Kw) and did it myself. Saved more than half, cost about $19k. Grid tie and working as I hoped. The Solar Edge Optimizers are definately something to consider for those of you out there thinking about it. I'm just a homeowner, no connection to the company. I subscribed to 'Home Power Magazine" for about a year before I did mine. Plus, I purchased the Dummies book for Solar Design. Both helped a lot. Then I had a company bid on my project to find out what size I needed. It's one of those industries that has basically a 100% markup in price. No offense to those who do this for a living, but it was more than I wanted to pay.

 

[SirReal63]

Here is an interesting analysis.

Report: Solar Is Cheaper Than the Grid in 42 of the 50 Largest US Cities : Greentech Media

It may be cheaper for many, but notice this little nugget at the tail of the article.

It's worth noting that the study assumes a 100 percent financed purchase at 5 percent interest over 25 years. Terms vary, but most loans are shorter, at ten to twelve years.


I suspect that not many people will qualify for a 5% fixed loan for 25 years, this also does not take into account the increase in property taxes that many face with improvements of this nature. You can bet if you had to get a permit for the installation, it will show up on your property taxes. I would be interested in seeing what the real numbers are for a 10 year loan with more typical interest rates for home improvement loans. I suspect it will change the validity of this article greatly. We paid outright for our setup but I know not everyone can do that.

 

[MossRoad]

I'll keep looking at it. But its gonna be hard to justify right now. Indiana has some pretty low electric rates while being the 9th largest consumer of electricity per capita. That means we have lots of power plants. That, coupled with the abundance of coal plants, our location at the crossroads of America (bazillion power transmission lines), several nukers nearby, natural gas burners, etc... which will keep rates lower for the foreseeable future, coupled with the clouds on this side of Lake Michigan gives me the feeling that this area will be one of the last in the country to see the fruits of solar power, subsidized or not.

But, I'll keep looking. I'd like nothing better than to be less dependent on local utility companies.

 

[SirReal63]

Grid tied with battery backup is the best way to remove some of that dependency but it comes with a hefty price tag. With traditional grid tied if the grid goes down so do you.

 

[Loren49]

It may be cheaper for many, but notice this little nugget at the tail of the article.

It's worth noting that the study assumes a 100 percent financed purchase at 5 percent interest over 25 years. Terms vary, but most loans are shorter, at ten to twelve years.


I suspect that not many people will qualify for a 5% fixed loan for 25 years, this also does not take into account the increase in property taxes that many face with improvements of this nature. You can bet if you had to get a permit for the installation, it will show up on your property taxes. I would be interested in seeing what the real numbers are for a 10 year loan with more typical interest rates for home improvement loans. I suspect it will change the validity of this article greatly. We paid outright for our setup but I know not everyone can do that.

The article also made this statement:
And in all but four of the 50 cities, solar is a better investment than the stock market.

These investment funds have the same costs whether used for solar or stocks.

Also many states have some level of property tax exemptions for renewables:
DSIRE: Incentives/Policies by State: : Incentives/Policies for Renewable Energy

Anyone who has money to invest could use some of the funds for solar. There currently are fixed rates under 5 percent if you have good equity in the hoe or a good down payment. Many would find that their payment on the loan would be considerably offset by the lowered or eliminated power bill. If they have a 10 - 15 year loan, after that time period they would have no loan or electric bill.

Certainly not for everyone and I suppose there is a saturation point for the grid but we're no where near that presently.

Loren

 

[SirReal63]

The article also made this statement:
And in all but four of the 50 cities, solar is a better investment than the stock market.

Loren

I suppose it is if you are basing that off of a 5% fixed for 25 years.

 

[houstonscott]

I suppose it is if you are basing that off of a 5% fixed for 25 years.

Funny, how when the details are examined the bias or slant is discovered in the favor of the industry doing the study. HS.