HomeLatest ThreadsGreatest ThreadsForums & GroupsMy SubscriptionsMy Posts
DU Home » Latest Threads » Forums & Groups » Topics » Environment & Energy » Environment & Energy (Group) » Coal fights back with cla... » Reply #7

Response to kristopher (Reply #6)

Sun Dec 8, 2013, 09:50 PM

7. Good Article

Kristopher I enjoyed the article and is it is a good stab at theoretically trying to match the generation to the load using the least cost low carbon model. I wish I could sit face to face and discus I think it would be a great discussion.

Many of the assumptions are purely academic and do not reflect actual costs or total owning costs. The assumptions that the study did not calculate " The model is computationally-constrained, so we did not include additional computing-intensive considerations, such as how much additional transmission is optimum, or reliability issues not related to renewable resource fluctuations." The model only looked at PJM as an Island and did not look at the interactions with other Grids like Midwest Iso or SERC. ERCOT would have been a better case study since it is closer to an Island before Tress Amigos. For renewables to possible work at high penetrations as the article points out storage is need for load match this is not the factor. Reactive power requirements and stability are not addressed since they are not considered part of the renewable argument. Stability and reactive power support are major cost contributors and have everything to do with preventing massive power outages. The control systems used for the renewables create harmonics and subsyncronuse resonance issues that will need to be designed out. A lot of RTDS simulation study is on going to create international standards standards for wind and PV controls. I have read several papers that will be presented at the 2014 CIGRE Symposium. Currently a large penetration of devices creates power quality and reliability problems. Germany and Spain have significant issues currently. Germany's problem is harmonics and voltage control, Spain's is stability. Spain had a country wide black out in 2009 due not just to load match but dynamic interaction between generators and wind turbines. Red Electric has a 35 % wind turbine penetration with designs from multiple manufactures. None of the factors as well as cost to eliminate stability and harmonics problems are considered in the study. We had a similar black out in Texas 2009 of almost 700,000 due to the wind just stooped and not enough spinning reserve.

The real world problem is transmission line congestion and the generation remote from the load. The constraint is getting the storage energy or needed spinning reserve where the problem exists in a way to prevent a Fault Induced Delayed Recovery Event or prevent small signal noise . The article did a good job of making my point about storage although I am in favor of transmission and the article is geared toward point of use. Currently there is the need for significant installation of storage. Table 8 makes makes my argument on the study. This is energy not just battery storage. California benefits on pump storage hydro and geo thermal to make the penetration greater than 50 %.But this does not deal with reactive power needs or stability issue for dynamic issues in the grid. The article tryies to make the case for electric vehicles and assumes the electric infrastructure is in place to deliver the power to the grid. The delivery of stored energy from electric vehicles is constrained by the size of the electric service from the house to the distribution connection. Only in the south where you have large air conditioning loads do you have enough capacity in the house service to deliver GIV to the distribution grid. This is one of the issues dogging the industry with smart grid power reduction charging or delivery. Infrastructure is a significant hurdle for GIV thats why I like transmission storage. A lot of services will have to be changed to make GIV a realty since the current market rules of "net zero" do not allow the end user to recover the upgrade cost.

"What you've written is somewhat accurate, but some critical elements are inaccurate and the emphasis is inapt as it creates the impression that there is some sort of technical barrier or massive storage roll out effort that must be accomplished before we really get down to concentrating on the generating side. That simply isn't the case." Your answer is nieve and I hope not based on the article you are quoting. A lot gets published and DOE provides funding for a lot of subjects that need or get peer reviewed. The IEEE does a lot of this type of checking.

With all due respect my analysis comes from working in the industry for the last 30 years as a power engineer. Your analysis is not accurate and is narrow. My statements are not academic but come as an engineer trying to over come the obstacles in the real world. There is a huge technical hurdle to a large role out of renew ables that has yet to be solved before a role out can occur. Work by ISO's and industry is ongoing. GIV will not take place with out legislation and some technical innovation. A lot of study is going on currently mostly funded by DOE. I worked a lot with EV's and batteries in the 80's, testing Lead acid NiH and Li. All of these technologies are not what we need to get us to the goal of large PV penetration. All battery technologies have significant operating costs. I am a big proponent of graphine capacitors which have the same storage density per square inch as Li batteries but the production techniques have not been worked out. Graphine capacitors are much lighter and have a critically short charging time. The problem is Graphine caps are ten times the cost of LI batteries so at this time not practical. Research dollars should be spent on refinement to lower the costs to make the technology comparable. The other technology that could provide storage is using wind to produce hydrogen. Hydrogen is clean burning and transportable. Several countries are starting to use this storage option but not in the US. I like the idea of point of use storage (GIV) but we are many years away from making this as reality. For one we need more skilled people to design and install the technologies. During the 90's the drive for a competitive system for generation practical eradicated Power Engineer. Only a small number of university even offer Power Degrees as an option as an undergraduate. The retirement and turn over in the industry is a hurdle for sure. Infrastructure replacement, CIPS, GIC mitigation and terror mitigation take the resources away from development of low carbon energy development.

My comment on CT's vs Wind are based on a local and world view look at what new generation has been proposed in PJM due to the announced closing of old coal generation. Approximately 30 % of them generation in the north east and PJM was coal. Wind projects are not being crated to replace the generation. Natural gas CT's are. I think more should be replaced with renewables to create more diversity but this is not the case. Don't put all your eggs in one basket approach. If the price of natural gas goes up everyone gets hurt. A great example of what I am taking about is China they do what ever is the cheapest solution. If wind were the answer they would not be commissioning one coal plant a month. Wind is not a significant part of there generation portfolio. Same for Japan when they shut down there Nuc's, Japan is building CT units to replace generation not installing more wind. Its because large renewable penetration is not ready. MEPPI is doing a great amount of research and is trying to run several of there plants on just PV. Significant harmonic and voltage quality issues are being overcome with the development of new controls and new STATCOM technologies. These are BETA units but are performing great. MEPPI has a Nickle Metal hydride interface UPS for point of generation that perform vary much what I am describing but is primarily used only to provide time to dispatch additional CT generation to the grid. This new technology is a great advantage for wind turbines.

On the back up issue for coal and Nuclear the same requirement as wind exists for spinning reserve. The power system operate s differently than it did ten years ago when the integrated utility was required satisfy all the mix of generation. With the deregulation creation Generation companies transmission companies and distribution companies. All generation bids in to the market at a price. Coal does not have any special requirements for redundancy or function like Nuclear. The back up is created by the amount of calculated reserve and penalties for not being able to meet contractual obligations. This is one of the reasons why Natural Gas CT's are the principal generator and not coal. The EPA regs were potent but a justifiable reason is coal can not compete with natural gas in the market place. There is no specific back up cost for generation in the modern market place. The market has a rate for generators to be available for stand by in case one of these other units trips or is not available. Free market companies build and dabble in this market.

I disagree that coast of integration is insignificant. many wind projects require SVC's to mitigate voltage and reactive power making the projects cost prohibitive. An SVC is an 18 million dollar adder to a 10 million dollar wind project. A lot depends on location and how close the wind project is to a stiff generation source. The use of large transmission energy storage is a better alternative then facts devices. This is where I am coming from. Cheap reliable grid storage solves many problems. Matching load to generation to a renewable source is just one aspect integration.

All this being said I am real proponent on renewable energy. We have many things to work out before large penetration will be practical and affordable. Congestion in the grid prevents a lot storage and generation from making a renewable grid relabel and affordable. New technologies and research on going will solve most of these issue and allow wind and solar to become a market driven first option.

Kristopher hopefully we can discus this one day at an IEEE, CIGRE or NERC meeting I am afraid I did not provide enough detail to satisfy your curiosity. Take care I am traveling the next to weeks and can not explain myself more the time difference is a tuff one. You have the right ideas and I think there is a lot we can learn from each other.

Reply to this post

Back to OP Alert abuse Link to post in-thread

Always highlight: 10 newest replies | Replies posted after I mark a forum
Replies to this discussion thread
Arrow 7 replies Author Time Post
kristopher Dec 2013 OP
bloomington-lib Dec 2013 #1
randr Dec 2013 #2
Searay60 Dec 2013 #3
kristopher Dec 2013 #4
Searay60 Dec 2013 #5
kristopher Dec 2013 #6
LineLineLineLineLineLineNew Reply Good Article
Searay60 Dec 2013 #7
Please login to view edit histories.