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Putting the Grid at Risk

May 28, 2013

The grid may have been built in the last century, but it is still resilient and works well.

Yes, it could use some additions to increase capacity due to growth.

What it doesn’t need is tampering to make it accommodate distributed generation, largely the result of renewables.

The grid was designed to provide transmission and distribution from centralized power generation sources … not from a plethora of minuscule generation sources, such as PV mounted on rooftops.

The industry is being driven in that direction by having to comply with Renewable Portfolio Standards (RPS) also referred to as Renewable Energy Standards (RES).

These laws require utilities to supply a specific percentage of electricity from renewable sources, such as wind and solar. Hydro is usually excluded as a renewable source.

RPS laws start by initially requiring a very small percentage of electricity to come from renewable sources, and gradually increase the requirements until higher percentages must come from renewable sources. For example, California law dictates that utilities must provide 33% from renewable sources by 2020; Illinois 25% by 2025; Colorado 30% by 2020.

Approximately 26 states currently have RPS laws.

At present, the required amounts of renewables are small; typically 1% or 2%, and the impacts on consumers have been too small to be noticed. The impact on consumers will grow as the percentage of renewables increase.

The impact on utilities is already great, as they attempt to prepare for the greater impact of renewables on the grid.

Utilities have to turn cartwheels in an effort to accommodate renewable sources.

There are three incontrovertible facts about RPS:

  1. RPS increases the cost of electricity.
  2. RPS requires extensive manipulation of the grid, with each tweak making the grid weaker.
  3. The states are implementing RPS so as to cut CO2 emissions.

I recently attended a conference on energy storage, since storage is the holy grail of wind and solar.

The proposed methods for storing electricity include batteries, pumped storage, compressed air energy storage (CAES), hydrogen storage, plus a few other more fanciful methods.

Huntorf, Germany, CAES plant. Photo from DOE.

Huntorf, Germany, CAES plant. Photo from DOE.

 

Batteries are very expensive and don’t have the capacity to meet the demands of the grid. They can be used to provide back-up electricity locally for short periods of time, depending on the size and number of batteries.

Pumped storage works and can be useful, however it requires storage of water behind dams where the terrain is suitable. It’s also expensive.

Electrolysis, using the excess electricity from wind farms, can produce hydrogen that can be burned in turbines to generate electricity when it’s needed … at an additional expense.

CAES was covered in detail at this conference. Two or three installations have been built at a cost of roughly $500 million each; one in Germany, another in the United States.

The compressed air in these installations is stored in underground salt caverns.

All of these methods are costly and will increase the cost of electricity to consumers.

None of them are included in the advertised cost or levelized cost (LOCE) of wind or solar.

What was fascinating, and at the same time tragic, was listening to the paroxysms that utilities had to go through to accommodate wind and solar.

The General Manager, who was demonstrably smart and capable, of an important utility, described how he developed a strategy of regional and local storage to maximize the amount of renewables that the transmission lines could accommodate. He dismissed batteries, for the reasons outlined above.

He explored salt domes with geologists for regional storage of compressed air. Salt domes require multimillion dollar investments, as much as $25 million just to determine whether the site is suitable. He was identifying ways to store compressed air locally to accommodate local interruptions to the distribution system.

He was anticipating that PV solar would become so large on his system, by around 2017, that it would hollow out his traditional power generation capability during the day, requiring him to shut it down or run it at reduced load, i.e., load following … the most expensive and damaging way to run his generating plant.

After he completed his hour-long talk, I asked him whether he would be taking any of these actions if it weren’t that the government was forcing him to meet its renewable portfolio standards.

His answer was quick, concise and significant.

He said … No.

*  *  *  *  *  *

 

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© Power For USA, 2010 – 2013. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author, Donn Dears, LLC, is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Power For USA with appropriate and specific direction to the original content.

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16 Comments leave one →
  1. Mary Hartman permalink
    May 28, 2013 9:41 am

    The American people, and to a great extent our leadership, have been seduced by the romanticized view of industrial wind created via the industry. Any who challenge the perception based fluff are ridiculed and called names, as were those who would say that the Emperor did not actually have robes of finely woven cloth, but that he was naked. “You are ignorant.” “You are daft.” “Only the wisest can see the garment.”

    This perception based policy is leading to national insecurity on so many levels, and to achieve a perceived benefit. It’s really disappointing.

    Mary

  2. May 28, 2013 9:50 am

    Mary:
    Thanks for your comment.
    You are correct, and the Emperor’s Clothes is an apt analogy.
    People are being hood-winked into thinking that wind and solar, and the RPS that requires them to be built, are necessary.

  3. June 2, 2013 5:51 pm

    Donn,

    Once again, I very much appreciate your observations and analysis. I’m going to ask this grid operator to read and respond to this post (here’s his blog, which includes pieces on demand-side management of distributed solar PV electricity):
    http://photoelectricdreams.blogspot.com/

  4. June 2, 2013 5:56 pm

    Here’s one of his posts, by the way, on demand-side management:

    http://photoelectricdreams.blogspot.com/2013/05/answering-variability-with-vanilla.html

    • June 3, 2013 9:55 am

      OK, thanks.
      I’ve read his post and will answer the best I can.
      Donn

  5. Photomofo permalink
    June 2, 2013 9:07 pm

    While I agree that RPS standards are for the birds I don’t agree with your assessment of wind or solar. We’re managing to integrate wind without much hassle in my BA. Right now at this very moment I’m importing 215 MW of wind. We have nearly 750 of spinning reserve available so we’re completely covered. Sometimes we get about 20% of our power from wind and we’ve yet to have any issues. I know others are but we’re working on solutions. Wind prediction is getting better every year and aggregate smoothing helps. We’re also moving to 15 minute scheduling which helps wind because you can schedule it in smaller blocks of time. It’s a lot easier to predict 15 minutes worth of wind than it is to predict 30 minutes or 60 minutes. Personally I look at integrating wind as a big math problem. If the economics justify doing the math then do it…. If they don’t don’t.

    Wind may not be the cheapest source of new power (natural gas is at the moment) but it’s certainly competitive with new nuclear plants, new hydro plants and close to the cost of new coal depending on the pollution technology employed. Last I heard the cost to firm up wind is 1.5 cents/kWh but I’d expect that number is lower now.

    I run several dozen power plants. I run some generators at partial load quite frequently. As long as the units stay out of the rough load zone I don’t care if they’re at 50% power, 75% power or 90% power. Some units don’t like partial load but if you engineer them for load following it isn’t a big deal.

    • June 3, 2013 10:42 am

      Thanks for your input.
      You know your system better than I do, so I’ll try to single out some areas on which I can comment.
      First, re running generation at partial load, under load following conditions.
      The severity of the problem depends on the type of power plant. The coal-fired units suffer the most. Rapid temperature changes affect boiler wall and super heater tubes. There’s no question they will incur damage if operated this way. Newer boilers, may be better at this, especially if helical wall tubes are used, such as in ultra-supercritical plants.
      NGCC plants also can be affected by rapid temperature changes, but gas turbines are more resilient. Single cycle units are designed for rapid temperature changes, which is why some are being rated as able to come up to full power in 15 minutes.
      The damage may not be noticed until the next scheduled shutdown.
      What type of units are you referring to, when you say you haven’t experienced problems with load following?
      I think most agree that anything below 20% of wind can work, but things get progressively worse above that.
      Wind and solar are both more expensive than coal or natural gas. I know that the EIA has published data showing wind and coal at about the same cost, but they added a $15 charge for CO2 emissions to the LOCE of the coal plants.
      Getting to the bottom line:
      Why fool around with wind and solar when NG and coal are cheaper and can be base load plants? In the final analysis electricity will cost people more if we use these alternative forms to generate electricity.
      Unfortunately, nuclear at $6,000 per KW isn’t the answer, so we’ll have to see whether SMRs make sense.
      Re hydro: adding power gen equipment to existing dams is inexpensive.
      Storage is the holy grail of wind and solar, with pumped storage being touted as a way to store electricity. But that’s like building a hydro power plant.
      Again, why should we build expensive power systems rather than the systems that have been proven to be reliable and cost the least?
      Hope this makes sense to you. Without knowing the details of your system I could only respond in general terms

      • photomofo permalink
        June 3, 2013 4:05 pm

        I in the Navy we run nukes in load following mode. I’ll grant that cost is no object there but it’s technically doable. I also have experience with a few gas turbines but my main work today deals with hydro units. Thermal cycling is technical challenge but it’s well within our understanding. Big picture wise it raises operational costs and shortens the plant lifetime. But here’s the deal… load following with your NGCC or hydro units is 10 times cheaper than storage.

        If you take another look at all the loads in a house there’s a lot of it that’s discretionary. Anything with thermal mass can be configured with a small amount of thermal storage to give it more operational flexibility. For example a small ice battery would allow a refrigerator to operate through the night. You’d charge it up during the day – discharge at night.

        Water heaters and A/C all fit the bill and they are large loads. Again here it’s likely that some amount of thermal storage would be desirable. The remaining dispatchable loads are dishwashers, clothes dryers and perhaps pool pumps. Together this collection flexible loads surely represents over half the load in a typical home. If you were to look at the load profile of a home with solar coupled to an energy management system you’d see a flatter load profile than a normal home. You’d probably also see a lower peak demand depending on the climate. To me a flatter load profile with a lower peak is a good thing. Makes my job easier.

        In January the DOE released new LCOE estimates for Coal, Nuclear, Gas, Wind etc. Wind is forecast as cheaper than new coal and nuclear. The IEA has published similar data recently that finds the same. The trends in increasing coal plant costs are striking. Whether wind is at parity, just a little ahead or just a little behind doesn’t matter so much as the trend over the last 10 years. Anybody comparing the costs of coal vs. wind would expect wind to become permanently cheaper than coal over the next few years.

  6. June 3, 2013 8:45 am

    Donn,

    I have cited to this post, and have included my grid operator friend’s response, here:

    https://sites.google.com/site/freemarketsolarpower/home/electricity-storage

    BTW, he says he posted a response here but it’s “awaiting moderation.”

    • June 3, 2013 11:00 am

      See my comments to his post.
      RE his article on demand management, it assumes people are willing to conform to when power is available.
      Refrigerators, one of his examples, can’t wait all day or night to operate.
      As I have mentioned on several occasions, there are very few appliances that can wait for power to be available, which is the thrust of his multi-panel approach to explaining demand side management.
      Air conditioning can be shut down for 15 minute intervals, but, unless you propose that we should allow the government to dictate how warm to keep our homes, that’s about the best utilities can do for demand side management for homeowners. New Zealand uses electricity to power hot water heaters, and they could be shut down for some time without affecting the homeowner. Where we have the same situation, it could fit a demand side management program..
      Once again, lights must be turned on after the sun goes down. People have to cook at specific times during the day. Refrigerators have to operate more or less continuously. About the only demand side opportunities, besides the two mentioned above, are to wash dishes and clean the oven at night,

  7. June 3, 2013 5:29 pm

    Photomofo:
    No argument there: It’s cheaper to increase maintenance costs than build storage.
    But why harm or destroy equipment?
    I haven’t done the calculation, but the refrigerator load is probably larger than a “small” car battery can handle.
    Yes, batteries can provide some storage for some appliances. Some have proposed putting batteries next to distribution transformers.
    Again, there will be a cost. Have you calculated the cost of batteries for back-up?
    Be sure to estimate replacement costs. I have a battery back-up for a sump pump that costs around $150 and runs rarely, but it’s supposed to be replaced every three to four years.
    Re LCOE: Here’s what is missing in your comment.
    The following is a quote from the latest EIA report at http://www.eia.gov/forecasts/aeo/pdf/electricity_generation.pdf

    “While the 3-percentage point adjustment is somewhat arbitrary, in levelized cost terms its impact is similar to that of an emissions fee of $15 per metric ton of carbon dioxide (CO2) when investing in a new coal plant without CCS.

    Coal is being penalized for emitting CO2, which slants the LCOE calculation. The LCOE calculation by the EIA is a political, not a scientific statement.
    Another point is that the EIA uses a capacity factor of 34%, but that is rarely achieved. On average, the capacity factor for land based wind is under 30%.
    These costs for wind and solar don’t include the cost of backup for when the wind stops blowing and the sun stops shining. It also doesn’t include the cost of transmission lines that must be built to bring the wind and solar (CSP) to where it can be used. Wind and CSP need dedicated transmission lines because of where the wind and CSP plants are built.
    One study said it would costs around $98 billion to build these transmission lines.
    I’m sorry, but wind and solar for grid applications are costly and unnecessary.

    • photomofo permalink
      June 3, 2013 8:23 pm

      I’m not talking about chemical batteries. I’m talking about a small 5 liter block of ice. That would be large enough to keep a refrigerator cold through the night with a fan used to circulate your stored heat. With A/C you’d need a considerably larger block of ice but the concept is the same. For water heaters you’d oversize your tank by double perhaps and add extra insulation. At scale the cost of insulated water tanks are around $100 per cubic meter in real installations. A cubic meter can hold a lot of btus for water heating or home heating.

      The idea of integrating wind isn’t to damage thermal plants. It’s to co-optimize the economics of both types of units. If wind does indeed become cheaper than coal or natural gas you’d want to displace coal/NG when there was wind available and then carry load when wind wasn’t. In my system we run our hydro as much as possible during the day, shut them down at night then import cheap coal and wind. Like I said before… Integrating wind is simply a big math problem. Can a system get 20% of its electricity from wind? 40% Depends on the resource mix, transmission availability and the costs.

      I don’t know and I don’t think anybody does yet how much wind and solar can be integrated. I do know that it’s a lot more than we used to thing.

      The quote you used about LCOEs is not wind’s fault. If lenders want to charge higher interest rates that’s their business. It’s normal for higher risk projects to pay higher interest. IOUs get one interest rate, IPPs another and munis another. That all gets plugged into traditional LCOE analysis. Wind isn’t causing lenders to charge higher interest rates on coal plants. Wind isn’t causing the price of coal plants to go up by 10% a year either. I honestly don’t know why coal plants are so much more expensive than they were 5 or 10 years ago. Same thing happened to nukes though.

      There are two or three different conversations going on here. In the first there’s the issue of integrating solar. Solar is integrated by the end-user. You don’t need transmission lines or chemical storage. You aim for self-consumption. My own preliminary estimates are that a homeowner in California with a demand of 6000 kWh per year could generate 4500 kWh with a 3 to 4 kW sized system, use 66% of the generation on site, sell the other 33% and buy the other half of their electricity from the grid. Depending on the retail rates the math can work. No batteries are required. The homeowner saves a little bit of money and becomes more self-sufficient. Down the road distributed solar could likely help us build a cheaper grid because homeowners can handle voltage optimization.

      The second conversation has to do with integrating wind. Wind is a wholesale resource so end-users aren’t going to install fancy appliances just for the hell of it. Wind has to work together with the other resources on the grid. If wind is cheaper there’s an incentive to work out the integration. There’s plenty of generation that’s highly rampable over a wind range so there’s no technical challenge there at low to medium penetrations. You have to consider that we ramp up every day and ramp down every night. Wind wind you’re adding an extra ramp. I don’t see it as a big deal. Just a math problem.

      Third conversation here is about LCOEs and what goes into them and what doesn’t. I look at the math a lot. My LCOE model for coal can be run with and without emission costs.

  8. June 4, 2013 7:17 pm

    Thanks.
    Your comments are great, though I disagree with some of your premises.
    Fundamentally, I don’t believe that wind or solar will ever, except in some specific locations, such as California, be less expensive than electricity generated using natural gas or coal: Unless economic storage becomes possible.
    The gist of my article is that attempting to integrate wind and solar into the grid is expensive, and unnecessary, and also adds complexity that is always deleterious to reliability.
    The analogy in manufacturing is to build with as few parts as possible. The more parts, the more things that can go wrong. The same is true with the grid.
    I am annoyed, however, by the EIA trying to promote wind and solar by denigrating coal with an added cost for CO2 emissions that’s not appropriate. The reason coal won’t be built for the next few years is because of the EPA’s requirements for CO2 emissions being less than 1,000 pounds per MWh, and not because of insurance.
    I’m annoyed by the EIA because most people don’t read the fine print and just assume the EIA is making a fair comparison … which it isn’t.
    I hope enough people read our combined comments, because I think people can learn from them.

  9. June 4, 2013 11:14 pm

    Very useful and informative debate here.

    I distill this from it: If self-consuming residential solar PV users flourish (and self-consumption by definition means marginal impact on the grid), the result is the same as enhancing building efficiency and thus reducing power consumption: A net benefit to the economy and the ecology.

    So I could not see any rational objection to backing distributed residential solar power generation, which would be greatly assisted by demand-side management ideas like Photomofo noted above.

    Here’s an example of self-consumption built Solar PV (thanks, Photomofo!):

    http://www.solarserver.com/solar-magazine/solar-news/current/2013/kw23/rec-supplies-pv-modules-for-36-mw-rooftop-self-consumption-pv-plant-on-audi-car-factory-in-belgium.html

    As for sharing grid costs between solarized consumers and the rest of the ratepayers, check out this analysis: http://reneweconomy.com.au/2013/more-solar-less-power-demand-higher-prices-does-it-add-up-78804 As you can see, it’s a highly nuanced debate.

    Finally, Donn, you state things like this: “Coal is being penalized for emitting CO2, which slants the LCOE calculation.”

    Of course, it’s not just CO2 that coal emits, but plenty of other forms of pollution. My question: Isn’t it worth something to you if renewables produce net less crap browning up the fish tank in which we all must swim? Isn’t fair to assign a dollar value to that crap, and thus weight the cost scales accordingly when debating brown vs. green power?

    This is, after all, a debate about costs — both dollar and pollution costs — and it’s fair to think about things like what my city (Savannah, GA) did. After a half century of “perma-fart” from the local paper plant, it put its foot down and made the plant clean up its act. Yes, paper now costs more, but Savannah now churns over $1 billion/year in tourism that surely would have been impaired by the persistent pollution the plant spewed on us.

    Trade-offs, ya know?

    Anyway, my thanks to both you and Photomofo. It’s a learning experience.

  10. June 5, 2013 4:15 pm

    Roof top PV solar for homes are no problem if: 1.There is no net metering so homeowner foots the bill and not his neighbor’s, and 2. He receives no subsidies, so tax payers don’t subsidize his roof top solar.
    Re Demand Side Management (DM): I don’t think many people will want to go back to using ice to provide thermal backup. There are very few instances where homeowners can respond to DM, unlike industry which can shed load efficiently and in large quantities. The fact is, DM is a burden on homeowners, with costs most homeowners won’t want to incur.
    Re coal-fired power plants. The new ultra-supercritical (USC) plants operate at 45% thermal efficiency vs 32% for old plants. The USC plant is nearly as pollution free as natural gas power plants and can meet all EPA requirements except for the 1,000 pounds CO2 per MWh requirement.
    Don’t lump USC together with old plants. USC is the epitome of clean –coal and are being built in Europe.
    Market forces should dictate what generation systems we use, not some bureaucrat in DC who doesn’t know what he/she is talking about or some Congressional Law that dictates what consumers can do (such as no more incandescent bulbs, or forcing homeowners to meet insulation requirements and having the home’s insulation score recorded on the deed, as required by Waxman-Markey cap and trade.)
    The EIA is deliberately trying to mislead people re LCOEs for different systems, much like the IRS has targeted tea-party groups.

  11. June 6, 2013 10:10 am

    A pleasure learning about improvements in brown power (coal, etc.) energy production.

    When you get down to it, Donn, we’re arguing about Big Government distorting the free market (I join in your aversion to that) and, frankly, cost. That is, the cost of power generation.

    A lot goes into the word “cost.”

    Look at the “avoided cost” term as defined by utilities, for example:

    https://sites.google.com/site/gridtiedsolarpv/home/defining-avoided-cost

    Consider also the embedded energy and pollution cost of making solar panels (some say 1-2 year payback on the energy consumed in making them; also, there is hazardous and other waste generated in solar panel and BOS manufacturing process).

    Compare that to coal extraction, processing, transportation, burning and overall pollution costs. Ditto for other brown power (natural gas, liquid fuel, nukes, etc.) costs.

    Plus, thanks to politics, we must also factor in and out the subsidies each gets, and the costs of those subsidies in dollar and political (corruption-breeding) terms (see Solyndra, Fisker Automotic, Range Fuels).

    It’s very complicated.

    And many omit various cost factors to pump the numbers behind the particular energy source that they favor.

    Some say add some pluses for solar because it avoids pollution costs, and minuses for brown power (anything that pollutes — coal, nat-gas, nukes). Some (like you) not.

    In fact, guys like you say Solar must be “charged” some grid-reconfiguration costs. At the same time, you’re silent about charging brown power for pollutants (yes, coal’s gotten better, but it still craps on us, right? And it still involves a lot of strip mining and other land-degenerating costs, yeah?).

    So yes, we must study “cost” down to meticulous detail, so that we may perform an intelligent cost-benefit analysis.

    That, in turn, drives debates like this.

    To that end, look at the unmistakable bias running through your entire analysis: You want to charge solar with grid-reconfiguration and other collateral costs, but you don’t want to charge brown with collateral pollution costs, much less land-disturbance costs like destroying mountains and leaving strip-mine gashings behind.

    That’s a political argument, no? I mean, we bespeak politics when we talk about whether to use the power of the state (via regulation, taxation, etc.) to impose a cost on a particular form of energy production (e.g., a fee for every square meter of radioactive waste to be buried under a mountain somewhere) and whether to de-subsidize (which affects net cost) a particular energy-production process.

    And it’s far too simplistic to say hey, let “market forces” decide when in fact huge portions of the energy market have NEVER been free-market driven. For both of my homes I’m stuck with monopolists who dictate what I must pay, and my PSC does not ban political contributions from them to PSC candidates; nor does Georgia law prevent brown power interests from greasing state legislatures on state energy policy, nor does Congress ban their bribologists from infecting that branch of government. New energy competitors thus face more than a free market in which to compete — they must lobby (bribe) their way past turf-protecting regulations and tax preferences.

    Politics. It’s a potent game. I encourage you to be more up front about yours and the way in influences your perception of cost, then your analysis of it. I say the same to greenies, many of whom seek to obscure renewable energy’s collateral and hidden costs (many, I find, are completely oblivious to grid-reconfiguration costs, which is why guys like you are especially valuable).

    That gets me back to my appreciation for your blog posts. You provide an enormous benefit with posts like this by elucidating a “cost” — green energy’s variability and grid-stress costs, of which I’ve collected research (including this very post) here:

    https://sites.google.com/site/freemarketsolarpower/home/electricity-storage/solar-power-s-variability-problem

    Through discussions like yours I learn a lot. You’ve inclined me to agree with you, for example, about whether many will adopt what sounds like costly demand-side-management techniques like ice-based devices. But I’m betting (Photomofo’s working on this) most will welcome “Smart Appliance” software, for maybe a dollar or more in cost, that enables things like Time of Use pricing-optimized operation (hence, my dishswasher runs, after I’ve pushed the button, at that precise time of the night when electricity prices are at their lowest).

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