View topic - Cost of "clean" nuclear energy

It's not quite that simple. Yes, it is true that a hydroelectric forebay can act as a "battery" of sorts, but the water can't be held back indefinitely. The vast majority of forebays are held near their maximum capacity because the greater the difference between the forebay and the tailrace (called the head), the greater the power output and the higher the efficiency of the plant. This means there's not a lot of room for "excess" storage.

There are also generally maximum and minimum allowable forebay levels. Too high and you have a catastrophic washout as the water tops the dykes and dam, too low and you have a erosion issues as the dykes and dams are constructed for a certain water level. The breakwaters and riprap (large chunks of granite) only extends so far below the surface, and if the water level drops below, wave and wind action will "dissolve" the dykes quickly. Efficiency and output of the plant drops off quickly with lower head as well.

Hydroelectric plants do "buffer" the system, but only within a certain range. The time from full off to full output is about 5 minutes (compared to 8-12 or more hours for a coal plant, and 15 minutes for combustion turbines), so they are very flexible in operation and do scale back and "pond" when power prices drop in the off-peak times. It's much more practical to keep the thermal plants operating at their efficiency point and cycle the hydro plants rather than vice versa, so as the hydro plants are already providing this function for coal and NG plants, there isn't a lot of room left for renewables like wind or solar.

Our power system in Manitoba is 95% hydro, with 1 coal-fired turbine, 2 turbines converted to burn natural gas rather than coal, and 2 purpose-built natural gas combustion turbines. The two combustion turbines were originally built as "spinning reserve", able to quickly provide "backup" power to the hydro plants and therefore allow them to draw down their forebays farther. They are typically only run to maintain their warranty. The coal and NG turbines hardly ever run.

Our system also buys power from one privately owned wind farm, with another one in construction. These wind farms were installed for purely political reasons, they add very little to the system and often use more than they produce. In our climate, they cannot operate below a certain temperature as the oil in the gearbox thickens up. They then sit idle, drawing massive amounts of power to heat the units. They also draw reactive power off the system as I mentioned before, putting further strain on the rest of the system. The existing windfarm, 63 turbines covering I don't know how many square miles, produces a maximum of 99 megawatts (and often run closer to around 30% of that), less power than a single generator in any of the northern powerplants, which all house between 10 and 12 generators each.

Manitoba still has 5000 megawatts of undeveloped potential on the Nelson River alone, which is already significantly altered by existing power plants. One plant in very early stages of development, Conawapa, would produce 1300 megawatts with around 1 (one) square mile of new flooding, and the waterway between the site and the current last powerhouse on the river, Limestone, is already un-navigable.

In some areas, wind and solar make sense. Our climate in Manitoba makes them nothing more than political chess pieces.

That said, and as I mentioned before regarding utility/commercial scale versus residential, my cabin is powered by both. That's where it does make sense.

This just isn't true.

Is Manitoba a remote island unto itself … is there no trade or commerce with this most sovereign of Provinces; do vast ocean depths, impenetrable mountains, or the crushing weight of glaciers prevent transmission lines from reaching it's borders; are there mongrel hordes who prevent entrepreneurs and foreign governments from sharing technology and resources with your locally distinct, web footed, and water breathing locals? I take your description of the grid and energy mix in Manitoba and the inflexible dominance of hydro (leaving little room for anything else) with an extreme grain of salt. You really need ALL of that hydro, all 95% of it, to back up two small coal and natural gas stations (a total of 468 MW generating capacity), a private wind farm, and NOTHING else? Please. If we're going to have a real debate, let's have a real debate!

I provided you with some numbers and current research that suggest the "back up power" conundrum is a non-sequitur as concerns variable energy sources (it's an outdated issue), that current grid management techniques and existing and new technologies are more than up to the task, and that utility level wind and solar are being integrated into existing grids all over the world (with few technical challenges). Cost is still an issue, but the technology is not. This doesn't mean there aren't poor performing wind farms, inefficient solar thermal plants still in operation, and that we haven't learned some hard lessons along the way. But the learning curve has been very quick when you compare it to technologies that are already 100-250 years old (and have already gone through their primary development phase). You know hydro development well, it is your business. You know small scale renewables well, you have them for your own home. I'd ask you (with all of your expertise and technical know how) to also look at some of the utility level opportunities around renewables (especially when matched to conservation, efficiency, and demand side management). I think you will also be similarly impressed. Whether it is the right choice or not for Manitoba might be a separate question to whether there is NO benefit to renewables on a utility scale (as a blanket statement). And I also have my doubts whether it is wise for Manitoba to have all of its energy eggs in one basket (certainly when managing water resource for environmental reasons and to honor specific agreements with FN is as important as generating power).

That quote is slightly out of context, at least in the context that I meant it, whether or not it came out right. I wasn't saying that there was no room for renewables on the grid because the hydro plants operate to back up coal and NG. I was saying that there isn't a lot of room in the reservoirs to hold back an indefinite amount of water when the wind is blowing or the sun is shining. To use hydro reservoirs as a "battery storage system" for renewables is not feasible because of how reservoirs are managed.

And I never said that our hydro resources were strictly to back up our coal and NG installations, I think you misread my post. Of course we have tie lines to other utilities, predominantly to the south through Minnesota, but we do have smaller tie lines to both Saskatchewan and Ontario. We are a net exporter of power, so unless market conditions dictate otherwise, we generate predominately with Hydro, and export everything that isn't used in province, and our thermal plants rarely operate. Our hydroelectric forebays, like every other forebay in North America, are operated according to regulations and market conditions, and these market conditions are driven primarily by thermal plants, as they are far and away the most dominant type of power plant in North America. Independent System Operators (ISO's) control market prices to influence line loading (prevent overloading of transmission lines). So, in essence, all Hydro installations in North America function as a buffer for all thermal plants in North America. Not our 95% hydro backing up our 5% thermal. I'm not entirely sure how you interpreted my response to read otherwise.

There may be all kinds of numbers and research out there, that's fine, but as it exists today (and that's all I'm saying), for every megawatt of alternative energy installed, there has to be a megawatt of traditional power (thermal or hydro) available at a moment's notice to back it up. That's the market, not the technology. Firm power sale contracts cannot be made with Alternatives, they are not allowed. They are allowable on the 5 minute spot markets, but no one can guarantee (and the market is based on guarantees) that the wind won't drop off or a cloud won't pass by.

I agree things are improving, and a megawatt is still a megawatt. Demand side management is the primary thing to address first. I'm not disagreeing with you here, idylwyld, I'm simply stating that as things exist today (not where they are developing towards), renewables play a very minor role in our energy solutions. In our system in Manitoba, that role is trivial at best due to our hydro development. Across North America all utilities are bound by the same regulations and the same market conditions. NERC (North American Energy Reliability Council) controls the regulations for all of North America. Due to the interconnectedness of the grid, there can't be an unstable source connected to the grid anywhere without adequate protection against cascading system failure. Renewables are just not there yet. I hope some day they will be, but RIGHT NOW they are not.

That sounds fair … I basically agree with this. And I appreciate the clarification. But it does seem like you are focusing a little too much on the challenges and not enough on the opportunities (you are obviously a glass half empty kind of guy when it comes to renewables).

In short, it seems like the arguments you are making have very little to do with renewables (actually). But how our energy system is designed (1960s era technology at best), and current conditions for energy pricing, markets, and regulations (which by necessity require standards for grid interconnection, dynamic reactive compensation, fault ride through requirements, and voltage stability). In fact, it's not renewables that are breaking the back of our current energy system, but how we use energy today (and the stress this puts on a system, peak demand loads, everyday work habits, seasonal swings, a world full of new digital gadgets, and the inability of our current sources to spool up quickly to meet these demand requirements and to fine tune loads). So the way we do this now is to pull in energy from very far away … Manitoba is a "net" exporter as you say, indicating it is part of this wider dynamic system of how our energy supply works. And this is why the 1:1 picture of adding renewables to a dynamic system has become a misleading and faulty claim ... if the wind is not blowing in Alberta, it surely must be blowing somewhere else (or there is a power plant in Tennessee looking to sell it's energy at an attractive rate). Manitoba could certainly engineer a better battery if it thought it could sell this energy and earn a substantial return on investment, maybe this would simply involve a subsidy by government or transmission and distribution providers to hold the energy in potential (for when it was needed). These challenges are not obstacles, they are actually opportunities for investment, new approaches, better regulations, provide greater security and reliability to an already stressed system, even reduce costs from poorly managing loads and outages (these costs are huge, an estimated $80 billion/year), and improve our limping along and struggling system. They need to happen regardless of whether renewables are added to the system or not.

You've properly identified why the status quo is no longer sustainable: a lack of storage (we actually have 2% built into grid now), no demand side management, and an inability to really monitor and closely fine tune a complicated network of generators, switches, circuit breakers and loads in a very active way (as a smart grid would be able to do). And many fixes are coming soon, or have engineers working on them (energy companies have historically been very conservative in their approach): HVDC transmission, high temperature superconductors, and smart grid developments (Texas, Colorado, and Ontario all have forward looking pilot projects … other countries are much further along with this). The storage issue may ultimately be resolved fairly quickly and effectively with V2G integration, vehicle to grid systems that address demand most importantly, but also may work as a massive and decentralized battery that becomes an energy source when it is needed. California is going to get up to 20% renewables this year (most likely … much of it wind). I think some areas can reach 40% with current system (this is widely accepted). But as you say, it's adding more stress to an already over burdened system. There are also some good opportunities for baseload renewables in some areas: solar thermal in Southwest, and geothermal in Rockies. That solar churns out electrons during times of peak demand is an asset rather than a deficit. And on and on.

Please read this short article: WIND POWER AND GRID RELIABILITY.

I've selected it very carefully as something that addresses most of your issues, is a quick read, and I think a good summary of where we are today and where we are going very quickly with renewables. I'd be interested to hear your view.

And I don't want this thread to get too far off track, but we have to look at nuclear too, and whether it helps or hurts this emerging energy picture. Many plants are run far below their rated capacity, in part because they are the least flexible of all these energy sources (and can ONLY be used for baseload generation). This too limits their effectiveness as a more widespread carbon reduction strategy. Our energy system is in constant flux. You can take a slice of it in any particular time and say "these are the problems." This doesn't tell me much. I'm more interested in hearing what are the solutions (and the trend lines are pretty clear at this point, I hold)!

I definitely appreciate the discussion, idylwyld. In regards to your first paragraph, I wouldn't see myself as a glass half empty guy in regards to renewables, more of a glass half empty guy in regards to society in general. I just don't think that, no matter how much people like you or I (or likely most of the others here on a canoing forum) try, we will be able to push the rest of the world off the path that they are on. That sounds pessimistic, and I guess it is, but I really do see a major societal crash in my daughter's life time, if not my own. Working day in and day out within the grid, I urge everyone I can to buy a backup generator for their homes if they have no other contingency plans in place. The grid is fragile, house-of-cards fragile, and every day more and more smart technicians responsible for maintaining and repairing the system either retire or quit, and very very few enter into the trade. On the continent, there is somewhere in the neighborhood of 14,000 vacancies in the field of Power Electrician/Electrical Technicians alone, not to mention the mechanics and millwrights and system operators. Yet every day, someone else comes out with a new "must have" gadget to add to the hundred other gadgets plugged into the wall. The vast majority fail to recognize the extent of the problem, and the vast majority of them wouldn't be able to understand the problem in the first place. There's too much money on the table, and I just don't see the people in charge of making the decisions choosing balance over profit. I hope and pray that I'm wrong, but I have a persistent feeling that I'm not. All I can do is prepare myself and my family and friends. Ok, doom and gloom over...

In regards to your second paragraph, that illustrates the very first comment that I made here:

In response to your reasoning that if the wind isn't blowing in Alberta, it likely is elsewhere, that's absolutely true, but with the current market and regulation structure, it's up to Alberta to back up Alberta's shortfalls. It's not that it would be completely impossible to co-ordinate power sales contracts between many different producers and transmission entities, but it would be a logistical nightmare, with the CURRENT set up. Opportunity exists, fair enough, but I see our brightest minds focusing more on how to produce a pill that melts fat away or keeps erections longer rather than reforming the electrical grid. More pessimism, but I've been in the industry long enough to have had a lot of the optimism beaten out of me. And you're 100% right, the system is struggling and major major problems exist that need to be corrected whether we add renewables or not.

HVDC systems are used for one of two purposes. Long distance power transmission from remote source to load centers, and in this respect Manitoba Hydro was and is a world leader:http://en.wikipedia.org/wiki/Nelson_River_Bipole (I happen to work at the Northern End of that system, providing technical training and technical support to Electrical Technicians and Power Electrician apprentices) This technology can be used anywhere where there is a source of energy that is a very long distance from populated load centers. Geothermal, tidal, desert-based solar thermal, whatever.

The second use, and probably more applicable in this discussion, is to increase stability on interconnected systems by "de-coupling" connected grids. These installations are back to back, meaning that the high voltage AC system on one side is rectified in HVDC, travels on less than 50 ft of buswork to a converter where it is converted back into AC. Every grid interconnection entering/leaving Texas follows this scheme, it is essentially a power system that can still import or export power from it's neighbors but is unaffected by whatever happens outside of it's borders, voltage level, frequency concerns, transient faults.

The major problem with these systems is that they are insanely expensive. The cost is justified in our case by the tremendous increase in efficiency (3-5% losses compared to 17-30% losses over 1000 km). I'm not sure how back-to-back system economics work out, but obviously they do somehow or they wouldn't exist.

I'm unfamiliar with high-temp superconductors, and I have mixed feelings on smart grids. The problem with batteries is that they don't last forever and introduce an entirely new set of environmental concerns. I would expect to see more movement on ultracapacitors as a storage medium of the future, but I can't see them ready in the foreseeable future. I agree that there are opportunities for baseload renewables in some areas, but the peak demand and peak solar times don't exactly line up. The load profile (in Manitoba anyway, and I would imagine is fairly standard) is high demand early morning as people wake up and machinery starts up, dropping off until a dip at noon, another slight peak around 1-2 or 3 (solar peak) as production picks up again after lunch break, leveling off until another peak around supper time, as everyone returns home.

I read the article, and I'm happy that there is movement in the dynamic compensation front. I hope the trend continues. It is about time that wind farms were held accountable for their affects on system loading and system stability, and it seems like they have a plan in place and it is advancing quickly. These are definitely good things.

One thing that you may or may not realize, though, is that the energy density for these installations is extremely low. It does add up, I'll give you that, but with an 80 MW farm here and a 10 MW farm there, you have to cover a large part of the continent with these machines to make a real difference. I am aware of and fully support roof-top solar initiatives in densely populated areas, they provide local power for otherwise unusable space. If you look at the amount of physical space required to produce 100 MW of wind or solar on productive land and compare it to a coal plant or a nuclear plant that pushes out 5000+ MW, there's no comparison at all. The need of energy isn't growing by a handful of MW's here and there, it's into the thousands, and although windfarms have a relatively small ground footprint, it does add up and that's loss of arable land that could be used for food production.

To try to bring everything back on track, I do whole-heartedly agree that renewable technology is growing, and needs to continue to grow. My gut feeling though is that as a stop-gap measure to carry us through to when they can stand on their own, nuclear, in my opinion, is one of our best bets. Not the old reactor designs, but the breeder type designs that are used overseas that reprocess their "waste" into useable fuel. This technology *CAN* be used to produce weapons grade material, but essentially makes nuclear waste a non-issue. For technology AS IT EXISTS TODAY, it will have the biggest, fastest impact.

Good debate though, you are pretty knowledgeable in these issues and it shows, rather than a lot of others who just think that we would all be OK if we add a few wind turbines and solar panels. I appreciate your optimism, and I hope that you are more correct on the future than I am.

HUGE THANKS for that! That's an incredible summary from someone who is shoulder deep in the thick of the industry, and it is a very helpful perspective (and I don't underestimate it in the least). I think I like your pessimistic comments at the outset best. As you (and others can probably tell), I'm not turned off by pessimism or challenges in the least, it just makes me want to try harder to understand their source, and figure out what needs to change. Maybe I'll have all of my idealism taken out of me in time, but I'm 41, work in city government in Chicago (via museums and universities), and it hasn't dissuaded me yet … but we are at an all time low point (and things seem to be getting worse). I think it goes in cycles, and I believe strongly there are such things as "game changers." Every now and then, we even get true leaders who know what they are doing and who muck up the works, create new conditions and force real change (which is always a collective effort). That being said, I don't believe in perfect solutions, and all we seem capable of doing as a society is moving the goal posts.

If ever I'm in Gillam (and that's pretty good bet in next 5-10 years for canoeing related stuff) … I'd definitely like a tour of the Nelson River power plants … or other hydro related/electricity transmission related facilities. I get along with most people, and do have a soft spot for people who don't think like me (and have the talent, expertise, and good humor to defend their views). I think that's why I enjoy interacting with Frozentripper and others on the site so much, and I don't think I thank them enough (because I learn a HUGE amount from them). And I know that we probably agree on far more than we disagree (and especially on those things that really make a difference to everyday lives and people). I'm probably even more a fan of debate than I am of solutions (I chalk that up to my training). If people are talking about what is bothering them in government, as a society, in their local communities, work, families, etc. … I think ALL has the potential to be good in the world. If people silently suffer, and "accept things" for as they are, I think we've lost the battle. It's my hope the internet (and sites this this), in all of it's anarchy, chaos and misdirection, can even come to our assistance in such things (and represent some small degree of hope). OK … enough of my looking at the glass half full.

That said, this thread has probably been a little over the top (but I think people will forgive me). I hope we can continue more of this in the future, and continue to discuss new developments and upcoming challenges (especially in the intersection of energy, economy and the environment … which I think has a core relevance to our focus on paddling, river stewardship, Canadian land and resource issues).

Just one last point relevant to this thread … came upon this article yesterday, and it seemed particularly telling and instructive to many of our upcoming challenges, and the pessimistic angle ("Power Line Project Faces Challenges in California Valley"). San Diego Gas and Electric seeks to add a 709 MW solar farm to the grid in the Imperial Valley in Southern California. The area has a huge potential of 16,000 MW (they claim) in solar, wind and geothermal potential (and huge urban centers nearby). These resources could be one of "the most productive renewable energy fields in the world," says San Diego Gas and Electric chairman (and California is in a mad rush to add clean energy to meet it's 20% obligation by sometime this year). But what stands in the way, you ask ... the antiquated grid and the resistance from misinformed environmentalists who have a "bee in their bonnet" about transmission lines. They seem to be impractical zealots who pushed for these reforms in the first place, but now balk at the practical ("real world") requirements of putting them into practice. I think the issue will eventually get resolved, with research, new approaches, better public education, leadership, but it's frustrating to see people who have the mentality that they want to have it all (and don't have to give anything up to get what they want in return).

California will be an important labratory to watch in the next 5 or 10 years. We're not spending nearly enough anywhere else to make any substantive changes to the status quo (tweaking around the edges), and so California will be our only real case study (and there are many other issues beyond energy, transmission, etc., that factor into the State's energy picture). To sum it up, I think we live in interesting times.Glad to know I have a future in Power and Electrical engineering in case I need one

Well, if you're interested, you could view this thread I made on solarpowerforum.net a couple of years ago while I was still working on the floor.

http://www.solarpowerforum.net/forumVB/hydro-power/1795-inside-hydroelectric-generator.html

There is a link to one of my photo albums filled with photos (and descriptions) that I took while a generating unit was down for regular maintenance. Most people never get to see the equipment in that level. They were taken at Long Spruce GS.

Just came across a distantly related story, from Europe, that illustrates how insidious radioactive contamination is. Remember Chernobyl and its accident, a long time ago somewhere in "Russia"? The consequences of that event still are present many hundreds of miles away and the radiation has an impact on taxpayers that fork out for compensation to hunters that cannot benefit from their quarry. Wild boars feed off the forest floor and whatever grows there still shows elevated radioactivity resulting in radioactive pigs...

http://www.spiegel.de/international/zei ... 45,00.html

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“What is the good of having a nice house without a decent planet to put it on?” - Thoreau

What's being left out here is the impact of radiation on humans relative to other environmental impacts... compensating boar hunters for game with elevated radioactivity is relatively insignificant, compared to the numbers of human deaths being caused elsewhere.

Radioactivity is an easy target because of the fear that it generates in the popular press. There is much more harm being done elsewhere.

In 2003, 30,000 Europeans died from excessive heat and smog blanketing the landscape. Poor air quality is responsible for many accelerated deaths, where often coal is burned. Coal mining kills thousands of miners every year, especially in China where coal reserves are abundant. Industrial pollutants being released in places like Bhopal, India have caused numerous deaths, illnesses and birth defects. Mercury in aquatic environments from industrial sources has affected thousands more. Mining toxins have polluted thousands of streams. A fifth of the world's humans don't have safe drinking water with millions of deaths and diseased lives resulting.

Yet the popular press still chooses to single out radioactivity as a significant hazard to human health. This is a real sign of lack of objectivity in the popular press, a real failure to report the world as it actually is. And a failure of politicians to take the initiative to focus action to where it's most needed.

Sorry for the rant. Financial collapse, rapid climate warming and flu pandemics seem to be in the press these days... no canoe trips, that's the reason.

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It's a good rant, FT - get it off your chest! Yes, there are tons of other evils that the public (press etc) tends to downplay.

Now, back to nuclear technology. The pig example is just a little reminder that, 25 years after the "spill", the consequences are still here - in places so far away that a link doesn't seem obvious.

That's a much abused logic that seems so convenient: it makes us avoid thinking about the nasty consequences of our chosen path.

To make wise decisions regarding our environment, we should make things not less complex than they are.

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“What is the good of having a nice house without a decent planet to put it on?” - Thoreau