Concentrating PV: A Cost-effective Option for Distributed Solar

Yes. Concentrating solar is the future energy option. Hitherto the criticism for wider application of Solar PV is its low efficiency and hence high cost of production of energy.

Dr.A.Jagadeesh Nellore(AP),India

http://www.marinavize.com/
thank you very much for information

Hi:

Its limited to clear sky areas where the bulk of the solar radiation is direct, not diffuse. This is true of any concentrating solar be it PV or thermal.

.....Bill

...pretty much....

.....Bill

The best choice for higher efficiency and cost effective is the CPV.

The table is not clear, but what were your ongoing operating cost assumptions for each of the three PV sites? It is obvious common sense that
* PV with tracking has higher wh/wp which tries to offset the higher cost of capital and higher O&M cost due to service & maintenance & management of tracking
* PV has a very known and low ongoing operating cost
* this CPV must have the highest ongoing cost of the three as it has tracking and cooling to deal with.

I like all RE more than non-RE but with the cost of the semiconductor portion of a completed module being so low, I'm not sure how CPV will find a market. Consider especially that is not realistically suited to residential rooftop which is where US subsidies are aimed.

Using concentrating technologies in thermal rather than electric applications makes more sense? E.g process heat needs in industrial or even very large hot water systems.

At tenKsolar, they use reflective light on a Monocrystalline half cell which are wired in a patented mesh network and boost the output of the cell by 50%. Check the design out at tenKsolar.com

To add on to MacAfrican's notion, what about hybrid PV/thermal? Suntech has some see-through panels. Maybe other manufacturers do as well? There have to be ways to do this that can individuate for particular climates and give affluent and thriving concerns additions to their product mix. Luxury purchasers are reportedly coming out of hibernation, according to some news reports. Add high-end stuff to the product mix to subsidize the low end and get more installed base. I would think somebody would be interested and able to gear this up. If companies do not do it, guys in garages are going to.

Comments are interesting. My question is of the comment that "Additionally, a CPV can offer higher output per square foot of occupied space".
How can this be,in that a given number of BTUS/sq ft fall on the earth? If you absorb all on a flat plate, or concentrate, it is still the same amount of energy that you have started with, whether concentrated, or not. In addition, the higher heat generated from concentrating will lower PV absorption/conversion efficiency.
Am I confused?

Chuck Scifers

probably depends on definition of occupied space - does it refer to the size of looking glass or the size of the PV that the looking glass focuses on...

QUESTION 1: Does Heat Rate apply to solar PV generation of electricity?
QUESTION 2: Does Heat Rate apply to solar trough generation of electricity?
QUESTION 3: Does more than 3412.14163 BTU have to go IN for each 1 kWh of electricity OUT?
QUESTION 4: Is the second law of thermodynamics repealed for solar and wind generation of electricity?
QUESTION 5: Would it be better for New Mexico ranchers to
install wind turbines to convert to electricity to power electric water pumps?
Or mechanically pump water from wind, as they have done in the past?

Sent: Friday, March 25, 2011 9:36:19 AM Subject: RE: Solar generation of electricity heat rate questions
I'm not one hundred percent clear that I understand the question you're asking, but I'll give an answer a shot:

I can start by pretty confidently saying that none of the laws of thermodynamics (or conservation of energy) can be violated by us...no matter what marketing language we choose to employ. So it is indeed a good exercise to compare output claims to available input to test whether some person's claims hold water or not. I used to do this as a hobby in the small wind area when people would periodically come out with claims that their particular vertical-axis wind machine somehow got around the issues of other machines and produced amazing amounts of power.

To attempt to address your heat rate questions, the term "heat rate" from an energy production perspective refers to the amount of energy a plant produces for every unit of fuel that gets put in. Specifically, it's the number of BTU's needed to produce one kilowatt-hour of energy. So strictly speaking, I would say that heat rate has no real meaning for solar PV or wind, since nothing's being burned. The efficiency of these technologies matters, of course, in that one wants to get as much energy output per unit input as possible. It's most important implication is how quickly we burn non-renewable resources to generate electricty. So he

So heat rate is really an expression of (thermal) generator efficiency that doesn't have an immediate analog in renewable techonologies since we don't consume non-renewable resources in the latter.

So strictly speaking, the amount of energy required to be input into any device that gets its energy from the Sun or the Wind is not directly relevant; again, because we're not actually consuming anything. What does matter, though, is how much land (read "real estate") is required to harvest energy, and how much it costs to do it.

On the Texas/gas issue, my understanding is that cold weather led to natural gas problems, which caused at least a couple of power plants to fail, which then caused electricity supply issues that led to further natural gas delivery problems... I believe the heart of the matter was an old and weak natural gas delivery system, not fundamentally an electricity generation or delivery problem.

As for your Wall Street banker - I'm not sure what to say. Is utility scale solar thermal a fraud? No. It's simply a matter of whether it's cost effective in the face of other options. Some of my clients sure think it is.

Finally, "is it better for NM ranchers to install wind turbines to convert to electricity to power electric water pumps, or use mechanical means?" (paraphrased) Probably mechanical. It's mechanical pumping you want in this case. You introduce a lot of (mostly) unnecessary losses by converting from mechincal to electrical to mechanical energy. That's why you see wind pumps scattered across the NM landscape. The advantage of electrical pumping is that it can be turned on NOW and turned off NOW. And since electricity is cheap and we're addicted to convenience, people do indeed use electric pumps in many cases.
Hope that helps.


Frank Currie, PE
Project Engineer
Commonwealth Associates, Inc.
1599 S. St. Francis Dr.
Suite C
Santa Fe, NM 87505
505-982-4012
www.cai-engr.com

Chuck,
In addition to being more efficient 40% versus about 20%, the main benefit is that CPV can use very expensive solar cells since they only use about 1/1000 of the cell area compared to flat plate solar. The efficiencies can still be pushed farther. I believe that the current record for a any PV system is a CPV system that is 42.8% efficient ( http://www.udel.edu/PR/UDaily/2008/jul/solar072307.html). They where however using fairly low concentration (20x). The 'Rainbow Concentrator' by Sol Solution (www.Sol-Solution.net) also promises to have higher efficiency by separating the light before it get to the cells at much higher concentrations.
CPV however only work well in direct sunlight. This is about 1/3 of the US and about 90% of Australia. Since the sunlight has to be focused, very little light bouncing off clouds will not generate energy. I think that you will eventually see the market specialized into three groups.
1) High irradiance (good sunlight), Cost sensitive, non aesthetic or space at a premium
This is where CPV shines (pun) intended. This would be solar farms, flat top roofs and possibly off grid applications in sunny places. Not that these require trackers to work, which gives an increase of another 30%. So compared to a flat top system, the CPV system will typically give (40%/20%)*(1+30%) = 130% more energy compared to a flat plate system.
Companies such as Sol Focus and Amonix are some of the bigger player.
2) Med-low irradiance (med to bad sunlight) space not at a premium
This is the thin film arena. First Solar dominates this market right now.
3) Med-low irradiance (med to bad sunlight) space at a premium, aesthetics important
This is mainly residential rooftops. Silicon solar panels dominate here. Some of the big players are un Tech and Sun Power

Could somebody please enlighten regarding the operating & maintenance cost of CPV?

Since the article deals with 1MW case studies I presume we're talking utility-scale not a little backyard job. At 1MW would CPV not involve (1) some rather impressive cooling infrastructure (therefore some rather painful piping, pressure, cleaning and water management) and in this specific case also tracking (therefore also need the O&M of a tracking system)? Tracking's O&M is magnitudes of non-tracking PV already, so add O&M of the cooling systems and I'm expecting O&M for tracking CPV to be three times the cost of capital at least (that's if anybody has MTBF for all the components).

Basically any LCOE comparison that does not deal with O&M cost is not worth the paper it's written on. Run the numbers again if the O&M on normal PV is 2.5% of capex and O&M of CPV is 15% of its capex.

I'm leaning toward saying that CPV would be very hard to get 80% leverage on till long term scale numbers are out there. Maybe Lehman Brothers would have taken on the risk.

The thin lens concentration technology being developed now by HyperSolar in Santa Barbara, California could definately shift the entire cost per watt equation with the power to increase efficiency of PV by 400% at low cost and reducing the number of cells necessary to generate a given level of power.

As a County Commissioner I am interested in promoting the development of solar energy in Hidalgo County. We have the new Sun Zia line that will be built in 2015(?) with a substation. There is a lot of buzz but how do we carefully deal with developing and at the same time encouraging safe growth of this potential. I am interested in attending trade shows, etc. any suggestions?

As a user of solar for pumping in remote locations I find it efficient and low cost and really like the idea of not being subject to power outages.

Clee - I am Vice President of Business Development for tenKsolar and I work on projects like you want to develop and help make that happen.

Please contact me at jloslebe@tenKsolar.com.

Sunny Regards, Jim

Clee - Opps, my e-mail address is: jlosleben@tenKsolar.com

RZimmerman - You may want to quailify your statment. The best efficiency for silicon is about 24%-26%, I believe the theoretical maximum is about 27%. For CPV there are now solar cells over 40% efficient. For thin film Solar Frontier has a 17.2% thin film solar cell, and there are current thin film pruduction solar cells bt Q-Cells at 13.4%. It is impossible for any of these to increase the efficiency by 400%!! For a very high concentration system the limit is about 72%. For a single junction non-concentrating solar cell the limit is about 27%.

MacAfrican - Yes, virtually all LCOE calcualtions use O&M. For CPV most systems are passively cooled. Most use a heat sink for the solar cell, so there are no pumps, and they only use water to clean the panels. For a comparison, for 1 MWh of power, CSP will use 4 gallons of water versus 720 gallons for Nuclear steam cooling towers. http://www.solfocus.com/en/downloads/sustainability/sustainability-flyer.pdf

The O&M costs are about double (much less than 1 order of magnitude) the O&M for PV. It is about the same as for wind.

http://files.zenithsolar.com/CPV%202010%20&%20Beyond%20Conference/28%20Levelized%20Cost%20of%20Electricity.pdf

You wrote
Power Production Wastes Water

By Frank Currie
Project Engineer, Commonwealth Associates, Inc.

According to "Estimated Use of Water in the United States in 2005," a report periodically published by the United States Geological Survey, of the 349 billion gallons of fresh water we withdraw from lakes, rivers and the ground each day, 41 percent is withdrawn to make electricity.

Most of this water is used in the context of burning coal to create steam for electricity generation.

By contrast, 37 percent of the fresh water we use is for irrigation, 13 percent is pumped for public consumption and the remaining 9 percent is used for industrial purposes and for livestock.

It concerns me that we use such a vast proportion of our most precious and scarce resource for something that, strictly speaking, doesn't even actually need water, and worse, is known to cause significant adverse environmental and health impacts. ...

Albuquerque Journal Monday November 29, 2010

which indicates that you are an electrical engineer qualified to answers the questions.

Honest response from a qualified electrical engineer is required to combat opinions not based on physical facts by those who lack quality engineering and physical science education to help identify financial scams.

Large scale solar generation of electricity is a fraud I was told by a liberal arts educated vice president of a large wall street investment bank several years ago.

That investment bank was reported to have lost $24.1 million of the well over $1 billion lost by investors in the Eclipse Aviation bankruptcy.

Your response to these four questions, and one more, will help answer whether the statement of the investment bankers is correct nor not.

Clee - Thanks for pointing out that link.
Sol Focus mentions over 25% efficient in another link:
"The high conversion efficiency of the SolFocus systems (25+%)"
http://www.solfocus.com/en/downloads/sustainability/sustainability-flyer.pdf
So it looks like they are not consistanst :^(

One big pet peeve of mine is looking at articles/marketing literature without dates. If anyone form Sol Focus is reading this, maybe they can comment and/or update their information.

Amonix
Amonix concentrating photovoltaic (CPV) solar power plants currently demonstrate AC efficiency of over 25% in the field.
Expected to increase by 10% in 2010. This would be 27.5%.
http://onlinelibrary.wiley.com/doi/10.1002/pip.1037/pdf

A far cry from the best concentrator cell efficiency at 40% but still more efficient the the flate plate technology.

US Sens. Udall push for renewable energy standard

U.S. Sens. Tom Udall of New Mexico and Mark Udall of Colorado are pushing legislation that would establish a national renewable energy standard for electric utilities.

The bill introduced by the first cousins would require utilities to generate 25 percent of their electricity from wind, solar and other renewable energy sources by 2025.

The standard would start at 6 percent in 2013 and gradually ramp up to the 25 percent goal.

...

The near-term potential for concentrated solar power (CSP) is assumed to be the minimum of the projected in-state electrical load and the actual CSP resources in that state. In all cases, the projected state electrical load is the minimum. Therefore, the near-term CSP potential is the electric load of the state in which the CSP resource resides. In 2020, the projected load for states for CSP potential is expected to be 12 percent of the total U.S. generation, creating an upper bound for CSP electrical generation. Assuming a 10,000 Btu/kWh heat rate for power plants, the estimated primary energy to create this electricity is 6 quads/year.

http://www.nirs.org/alternatives/factoid18.htm

From: 'Greg Nelson' Greg.Nelson@pnmresources.com
To: bpayne37@comcast.net
Sent: Sunday, April 10, 2011 12:46:21 PM
Subject: Re: heat rate for csp?

Bill,

Heat rate is the amount of Btu's of fossil fuel burned to generate kWh's of electricity. Since CSPs don't typically burn any fossil fuel (unless they have supplemental firing), the term heat rate does not apply to CSPs. I have included a definition of heat rate that I got off the net for further clarification.

A measurement used in the energy industry to calculate how efficiently a generator uses heat energy. It is expressed as the number of BTUs of heat required to produce a kilowatt-hour of energy. Operators of generating facilities can make reasonably accurate estimates of the amount of heat energy a given quantity of any type of fuel, so when this is compared to the actual energy produced by the generator, the resulting figure tells how efficiently the generator converts that fuel into electrical energy.

Greg


----- Original Message -----
From: bpayne37 bpayne37@comcast.net
To: Nelson, Greg
Cc: bpayne37@comcast.net bpayne37@comcast.net
Sent: Sat Apr 09 19:17:52 2011
Subject: heat rate for csp?
Hello Greg,

What is the heat rate for CSP?

Thanks in advance.

bill

____

Here's a link to Nelson's business card.

http://www.prosefights.org/wind/wind.htm#nelson

And here's how suspicion of fraud got started.

fast neutron
Santa Fe, NM
January 12, 2009

From actual experience, wind farms produce 1.2 watts per square meter. Solar Thermal and Photovoltaic methods capture 5 to 6 watts per square meter. There is no economy of size in either technology. Dividing the watts you need by those values gives the land area in square meters needed to produce the juice. The numbers are astronomical

http://www.topix.net/forum/source/santa-fe-new-mexican/T0QVJ5UD3R25C8HRL
---

Fossil fuels burned?

EPRI reports heat rates from nuclear and geothermal.

Post

"It is time that the state take control of this increasingly important issue."

Supposition that the state of New Mexico is utitilzing individuals' advice who have expertise and ability in the area of electric power generation is suspect.

We recommended that the state 1 Contract with NM geologists to attemp to forecast future BTUs available for electricity generation 2 Establish a board of those qualified to evaluate whether proposed solar or wind electric generation technologies are a scam or not.

http://home.comcast.net/~bpayne37/pnmelectric...

There is a LOT OF MONEY to be made developing and selling alternate generation facilities to those who do not understand the laws of thermodynamics, HEAT RATE, and CAPACITY FACTOR.

suggests oppotunity for fraud.

http://www.prosefights.org/unmineable/unmineable.htm#scholle

Fast Neutron response is seen above.

Google 'admiral william h payne' for more details.

From: bpayne37@comcast.net
To: "Greg Nelson"
Cc: scholle1@gmail.com, gretchen@gis.nmt.edu, fmcurrie@cai-engr.com, "CAI Info" , "Shirley A. Lancaster" , shumard@epri.com, askepri@epri.com, clperry@epri.com, clibby@epri.com, zalan8587@q.com, "ron chesser" , homan@nmgco.com, "steve casey" , "dru jones" , "sheila shaffer"
Sent: Monday, April 11, 2011 5:33:20 PM
Subject: Re: heat rate for csp? geothermal heat rate


Hello Greg,



Thanks for response.



You wrote, 'Heat rate is the amount of Btu's of fossil fuel burned to generate kWh's of electricity. Since CSPs don't typically burn any fossil fuel (unless they have supplemental firing), the term heat rate does not apply to CSPs.'



Then why does Geothermal have a Heat Rate of 29,050 BTU/kWh?



regards,



bill

http://www.prosefights.org/unmineable/unmineable.htm#scholle

From: "Greg Nelson"
To: bpayne37@comcast.net
Sent: Monday, April 11, 2011 5:34:21 PM
Subject: RE: heat rate for csp? geothermal heat rate


Don't know.




--------------------------------------------------------------------------------

From: bpayne37@comcast.net [mailto:bpayne37@comcast.net]
Sent: Monday, April 11, 2011 5:33 PM
To: Nelson, Greg
Cc: scholle1@gmail.com; gretchen@gis.nmt.edu; fmcurrie@cai-engr.com; CAI Info; Shirley A. Lancaster; shumard@epri.com; askepri@epri.com; clperry@epri.com; clibby@epri.com; zalan8587@q.com; ron chesser; homan@nmgco.com; steve casey; dru jones; sheila.shaffer@state.nm.us
Subject: Re: heat rate for csp? geothermal heat rate



Hello Greg,



Thanks for response.



You wrote, 'Heat rate is the amount of Btu's of fossil fuel burned to generate kWh's of electricity. Since CSPs don't typically burn any fossil fuel (unless they have supplemental firing), the term heat rate does not apply to CSPs.'



Then why does Geothermal have a Heat Rate of 29,050 BTU/kWh?



regards,



bill

http://www.prosefights.org/unmineable/unmineable.htm#scholle

Some people are very upset about what happened.

Sunday, January 07, 2001 5:52 PM
Dear Friend,

we saw some of these documents http://www.geocities.com/CapitolHill/Congress/8327/buehlerpayne.html but we would like your commentary about what happened and all circumstances so we can post it on our website but as well as a report to the mailing lists.

With thanks

On behalf of SMCCDI

A. Zoubin ( Information Committee) http://www.iran-daneshjoo.org/


Wednesday, January 17, 2001 7:10 PM

Dear Friend,
A stand for Ahmad but why this question?