Grid-tied solar

farmeratheart · Jan 30, 2014

Yeah- with the snow that we have gotten down here just south of the Mason-Dixon line, we have had several days of 0 or almost 0 kWh ...

dave1949 · Jan 31, 2014

The January, 2014 results.

Below the model this month by one good sunny day, or two so-so days. Way below last January too. Lots of gloomy/rainy/snowy weather the first three weeks of January.

Last year, the total system output exceeded the annual model prediction by 12%, or 540 AC kWh.

Month--NREL Model (AC kWh)-----2012 Actual-----2013 Actual-----2104 Actual

Jan.----388----------------------NA--------------440-------------360
Feb.----412----------------------NA--------------375
Mar.----509----------------------NA--------------462
Apr.----374----------------------NA--------------487
May----353----------------------NA--------------375
Jun.----308----------------------NA--------------379
Jul.-----341----------------------NA--------------377
Aug.----383----------------------461-------------470
Sep.----394----------------------481-------------476
Oct.----369----------------------378-------------453
Nov.----283----------------------400-------------414
Dec.----331----------------------297-------------278

dave1949 · Jan 31, 2014

Now that I have some history, I can revisit the system payback calculations. My installation included replacing propane-fueled domestic hot water with electric which made it difficult to guess how much propane I use for cooking and how much for DHW, and how much the electric water heater would increase our usage.

Now I can see that cooking accounts for 70 of the 315 gallons of propane we used each year leaving 245 gal. for DHW. The cheapest I have ever bought propane here was $3.05/gal., I will use $3/gal as a cost. 245 gal X $3 = $735 per year in saved propane costs.

The system produced 88% of our total 5664 kWh annual electric usage. Our rate is $0.14/kWh. (5664 X .14) X .88 = $698 per year in saved electric costs.

The total annual savings, propane + electric = $1,433.

The total cost for the installed solar system and electric water heater was $19,774.
19,774 / 1,433 = 13.8 years.

The state rebate and federal renewable energy credits totaled $7,932, or $11,842 net system cost after rebates and credits.
11,842 / 1,433 = 8.26 years.

Certainly, the cost of foregone interest or earnings on the system cost need to be considered, as does the rising cost of electric service and perhaps propane. Propane is never cheap here, I have paid as much as $3.60/gal. in normal times--which is a "shortage" price for folks in the Midwest.

farmeratheart · Feb 3, 2014

Thought you might like to see how the 3+ years of our system performance look ...

Monthly Solar Output of 4kW Array

Month/Year 2010-11 2011-12 2012-13 2013-14
October 538 250 361 424
November 414 380 349 388
December 313 319 242 246
January 268 411 328 270
February 421 429 336
March 563 525 446
April 440 585 582
May 511 518 558
June 580 576 520
July 620 541 510
August 518 552 497
September 518 511 576
Yearly Total(kWh)5704 5597 5305 1328

Here's to hoping for a sunny year!

dave1949 · Feb 28, 2014

The February, 2014 results.

Above the model this month by one-two sunny days. Well above last February. It's good to see a sunny month after Dec. and Jan.

Month--NREL Model (AC kWh)-----2012 Actual-----2013 Actual-----2104 Actual

Jan.----388----------------------NA--------------440-------------360
Feb.----412----------------------NA--------------375-------------446
Mar.----509----------------------NA--------------462
Apr.----374----------------------NA--------------487
May----353----------------------NA--------------375
Jun.----308----------------------NA--------------379
Jul.-----341----------------------NA--------------377
Aug.----383----------------------461-------------470
Sep.----394----------------------481-------------476
Oct.----369----------------------378-------------453
Nov.----283----------------------400-------------414
Dec.----331----------------------297-------------278

MtHam · Mar 3, 2014

cqaigy2 said:
You mean when they de-regulated it and let the company's set the price etc?

No, California state government under Grey Davis decided that to 'protect' California from market price swings of wholesale power they would lock us in to long term contracts that proved to be disastrously over priced. Another example of how big government is inept! How's your government mandated health care working out?

houstonscott · Mar 3, 2014

When the companies have set prices costs went down. When government gets involved prices go up. Yeah you were taught in California schools that the monopoly's were bad, but Standard oil lowered price of fuel from $4.00 to .35 cents, an inconvenient truth left out of your history books. HS

Loren49 · Mar 3, 2014

houstonscott said:
When the companies have set prices costs went down. When government gets involved prices go up. Yeah you were taught in California schools that the monopoly's were bad, but Standard oil lowered price of fuel from $4.00 to .35 cents, an inconvenient truth left out of your history books. HS

Do you have any references to support this claim?

Loren

houstonscott · Mar 3, 2014

Loren49 said:
Do you have any references to support this claim? Loren

http://www.fee.org/the_freeman/detail/john-d-rockefeller-and-the-oil-industry
Unfettered free markets are a great thing, built the country and the world. Everyone won. HS

BobRip · Mar 3, 2014

houstonscott said:
John D. Rockefeller and the Oil Industry : The Freeman : Foundation for Economic Education
Unfettered free markets are a great thing, built the country and the world. Everyone won. HS

Good article. It looks like Rockefeller did best when I faced competition such as the Russian oil. He did not always have a monolopy.

Loren49 · Mar 4, 2014

houstonscott said:
John D. Rockefeller and the Oil Industry : The Freeman : Foundation for Economic Education
Unfettered free markets are a great thing, built the country and the world. Everyone won. HS

The overproducing of oil and the developing of new markets caused the price of oil to fluctuate wildly. In 1862 a barrel (42 gallons) of oil dropped in value from $4.00 to 35 cents. Later, when President Lincoln bought oil to fight the Civil War, the price jumped back to $4.00, then to $13.75. A blacksmith took $200 worth of drilling equipment and drilled a well worth $100,000. Others, with better drills and richer holes, dug four wells worth $200,000. Along side the new millionaires of the moment were the thousands of fortune hunters who came from all over to lease land and kick down shafts into it with cheap foot drills. Most failed. Even Colonel Drake died in poverty. As J. W. Trowbridge wrote, “Almost everybody you meet has been suddenly enriched or suddenly ruined (perhaps both within a short space of time), or knows plenty of people who have.”

Read more: John D. Rockefeller and the Oil Industry : The Freeman : Foundation for Economic Education

Article on life of John D Rockerfeller stated drop was due to overproduction

Those few who struck oil often wasted more than they sold. Thousands of barrels of oil poured into Oil Creek, not into tanks. Local creek bottoms were often flooded with runaway oil; the Allegheny River smelled of oil and glistened with it for many miles toward Pittsburgh. Gushers of wasted oil were bad enough; sometimes a careless smoker would turn a spouting well into a killing inferno. Other wasters would torpedo holes with nitroglycerine, sometimes losing the oil and their lives.

Read more: John D. Rockefeller and the Oil Industry : The Freeman : Foundation for Economic Education

Unfettered free market had/has its downsides. Not everyone wins when companies/individuals do not pay the cost of their pollution.

This article does not give good evidence of what you claim. Also just for comparison

In 2012, the relative value of $0.35 from 1862 ranges from $6.38 to $973.00.
In 2012, the relative value of $4.00 from 1862 ranges from $73.00 to $11,100.00.
Measuring Worth - Measures of worth, inflation rates, relative value, worth of a dollar, purchase power

The values you chose to support your claim were from 1862 on a barrel (42 gallon) of crude.

Probably not a good idea to hijack this enjoyable thread but your hollow claim needed to be addressed. The balance of free market and regulation is very complex and debated by many. Bottom line with solar is its working pretty well.

Loren

Redneck in training · Mar 5, 2014

Elon Musk founder of Tesla car company (among other things) said that burning oil is like burning furniture to heat your house. It would be more valuable to turn it in some other stuff of lasting value in example plastics.

Scooby074 · Mar 5, 2014

Redneck in training said:
Elon Musk founder of Tesla car company (among other things) said that burning oil is like burning furniture to heat your house. It would be more valuable to turn it in some other stuff of lasting value in example plastics.

Elon Musk is a very wise man.

He's starting up his own battery production. Can you imagine the world we'd live in if there were just 100 people like Musk?

houstonscott · Mar 5, 2014

Scooby074 said:
Elon Musk is a very wise man. He's starting up his own battery production. Can you imagine the world we'd live in if there were just 100 people like Musk?

Agree about Musk, but we have enough oil for a few thousand years, there is no shortage. While electric cars are interesting no electric car can match the efficiency of using the energy directly in the vehicle. Even Musk knows that! And with man made warming clearly shown to be a hoax, and CO2 found not to be a warming gas in climate change there is no urgency to reduce CO2. What solar does for you today is insulate you from government controls of your life style, coming in the so called smart grid. HS

Scooby074 · Mar 5, 2014

houstonscott said:
Agree about Musk, but we have enough oil for a few thousand years, there is no shortage. While electric cars are interesting no electric car can match the efficiency of using the energy directly in the vehicle. Even Musk knows that! And with man made warming clearly shown to be a hoax, and CO2 found not to be a warming gas in climate change there is no urgency to reduce CO2. What solar does for you today is insult you from government controls of your life style, coming in the so called smart grid. HS

What? That's completely inaccurate. All I'll say on the matter, so as not to ruin Dave's thread.

downsizingnow48 · Mar 6, 2014

I appreciate very much the work by Dave1949 and others to document their experiences and the technical and household financial issues involved. Kudos to all for this work. It is exceptionally useful for others, like myself, who are exploring solar power possibilities and beginning to think through options and trade offs. Many thanks.

Travelover · Mar 6, 2014

Scooby074 said:
What? That's completely inaccurate. All I'll say on the matter, so as not to ruin Dave's thread.

Thanks. I like TBN a lot more since they have tried to funnel all the divisive topics into the Front Porch section.

BobRip · Mar 6, 2014

houstonscott said:
Agree about Musk, but we have enough oil for a few thousand years, there is no shortage. While electric cars are interesting no electric car can match the efficiency of using the energy directly in the vehicle. Even Musk knows that! And with man made warming clearly shown to be a hoax, and CO2 found not to be a warming gas in climate change there is no urgency to reduce CO2. What solar does for you today is insulate you from government controls of your life style, coming in the so called smart grid. HS

Were you trying to be sarcastic? We are not sure and would appreciate confirmation one way or the other.

dave1949 · Mar 6, 2014

The system hit an all-time high today of 30.8 AC kWh. Temps in the mid-20's, clear sky, and reflective snow on the ground.

Theoretically, I should see similar outputs in September (the sun angle is the same as now) but the lack of snow and warmer panel temps reduce the output. The air was really dry today also. We had -7F this morning with just a hint of frost on the car outside, and none on the panels which are higher above the ground. I doubt if it ever gets that dry in September, which means more water vapor in the air reducing the sunlight intensity.

I appreciate everyone's interest in this thread. I'll keep plugging in the monthly performance as long as people are viewing. Of course, others are welcome to add anything of interest.