Insights When Renewable Energy Meets Power Grid Operations

[mfb]

It is hypothetically possible to build a power plant that sells nothing other than reserve capacity, never generating a single MWh in its lifetime.

Pure storage solutions are somewhat close to this - they use their reserve capacity (unlike your hypothetical plant) but they don't produce net electricity overall.

With less confidence, I also believe that withdrawal of all subsidies, priorities, and preferences would not slow down the growth of renewables significantly.

Germany's new solar installations dropped to essentially zero after the subsidies for new installations reached 120 Euro/MWh. At that level you wouldn't expect the market dynamics to be very important for the decision for or against new installations - you live from the subsidies anyway.

The problem with a carbon tax is that is has perjorative connotations compared to a market base adjustment. I would pay it happily, others would use the nature of approach to paint it as being anti-market.

I see a carbon tax as pro-market. Let the power plants pay for the external costs they cause.
Coal power plants would have gone out of business long ago if they would have to pay for the pollution and follow-up costs from CO2 emissions they cause.

 

[Rive]

Some people may think Germany was too heavy handed in that action...

Well, I too think that in this action, as mitigation for a self-created trouble Germany was actually right. The problem lies with the political background/implications.

Creating low prices by subsidies, then 'saving' their own only while pressuring the capacity of the neighbors the same time: not building the necessary infrastructure and intentionally maintaining bidding zones which are inadequate to follow physical flows while congesting the transmission lines of neighbors by loop flows: pushing the blame on the victims and wielding the whole 'green' thing as a tool for political warfare ...

As far as I know right now Germany has no cross-border link left which is not HVDC or AC with a PST guarding the flow due the reasons above. But about the bill and what it took to finally reach this point...

 

[anorlunda]

Creating low prices by subsidies, then 'saving'

That is what I call "tinkering" with the markets. Put in market features that are not fully understood, then adding urgent patches as the negative consequences become clear. Then patching the patches. That in a nutshell, is what made California vulnerable to Enron in the year 2000. When you tinker, you leave loopholes.

I do think that having a debate that centers on ISO's requirements for the operation of the "largest machine in the world" whereby said ISO's come out of the shadows, claim their thrones and say to the utterly dependent public - we need to have a debate with a specific mechanical outcome - i.e. fair pricing of carbon in order to operate this machine reliably - is a nice way of building an important bridge across that gap.

The problem is that the wholesale markets that the ISO runs are so abstract, and so removed from a consumer's monthly bill that the public doesn't understand, and the public is totally uninterested in these issues. Public opinion is more easily driven by inflammatory sound bites, and doomsday predictions.

In fact, unless there is a blackout or an impending crisis, the entire power grid is a crushingly boring subject for most people. I've learned from a lifetime as a power engineer, if I answer the question "what do you do?" at a party, the result is that people instantly walk away or change the subject. (Fortunately for me, I met my life's love before becoming a power engineer. :-)

Another cool project I had the opportunity to work on was a high fidelity simulation of possible evolutions of an entire state's generation portfolio with degrees of freedom including penetration of renewables, storage and demand-response. By high fidelity I mean down to day ahead commit and 5 minute economic dispatch with a linearly and stochastic-ally perturbed demand signal.

Please please, fund me to do that simulation. That has been my wet dream for decades. Not just me, but lots of other engineers. There have been several attempts, but the problem is difficult. You simplify enough to make it practical, then the results are doubtful because of the simplifications. It lies somewhere between first principle physics and economics, and predicting future Dow Jones stock prices.

Germany's new solar installations dropped to essentially zero after the subsidies for new installations reached 120 Euro/MWh. At that level you wouldn't expect the market dynamics to be very important for the decision for or against new installations - you live from the subsidies anyway.

I'm sure that's true, but there is a Moore's Law - like evolution going on here. Solar PV costs halve every 3 years. Wind is also making fast strides. Therefore, what failed 3 years ago, might thrive 3 years from now. Policy based on a 10 year future horizon is a pretty good way to do it.

Traditional power engineering thinks of physical facilities having a 40 year lifetime. That it challenged of course in a rapidly evolving world, but still 10 years per time step is not bad. So looking forward one step, I think of solar prices as $2^{-3}$ times today's price as a planning figure. That is clearly in the no-subsidy-needed range.

 

[PeterDonis]

I see a carbon tax as pro-market. Let the power plants pay for the external costs they cause.

This assumes that the government has accurate knowledge of what those costs are. I'm highly skeptical of this assumption in the case of carbon.

 

[anorlunda]

I want to be clear. I have no public pro/con position on carbon tax. I said only that it is less dangerous than putting a thumb on the market's scale.

 

[mfb]

Traditional power engineering thinks of physical facilities having a 40 year lifetime. That it challenged of course in a rapidly evolving world, but still 10 years per time step is not bad. So looking forward one step, I think of solar prices as $2^{-3}$ times today's price as a planning figure. That is clearly in the no-subsidy-needed range.

I would be really surprised if installation costs can drop that much. The modules - maybe.

This assumes that the government has accurate knowledge of what those costs are. I'm highly skeptical of this assumption in the case of carbon.

Well, it is certainly not zero. The pollution from ash is easier to estimate, and that alone would make coal not competitive any more.

 

[anorlunda]

I would be really surprised if installation costs can drop that much. The modules - maybe.

Your right. My number was misleading because of that.

The near future for installation of utility-scale PV is complicated because we expect many solar farms to be upgrading with new panels; perhaps once every 3 years. That partially re-uses existing installation investments. That is good, but makes forecasting more difficult.

 

[CWatters]

It seem that we still have things to learn here in UK/EU...

Regulators here issue REGO (Renewable Energy Guarantee Origin) certificates to renewable energy generators for each MWh they produce. These certificates are used to prove statements made about the Fuel Mix a particular energy company claims to deliver.

Unfortunately these certificates can be traded. So an energy company can buy electricity from a fossil fuel fired power station and market it as 100% renewable as long as they buy the corresponding number of REGO certificates.

For some reason these certificates trade for around £1 each. So the cost to an energy company per customer is virtually negligible. This means it's way cheaper to by electricity from a fossil fuel generator and green wash it by buying an REGO than it is to buy electricity from a renewable source.

Last year one company supplied 3.7% of their electricity from renewable generators, this year buy buying REGO they are able to claim all their electricity is 100% renewable.

 

[PeterDonis]

it is certainly not zero

Not if you assume that the effect of CO2 emissions is net negative, no. But I am also highly skeptical of that assumption. Just on the most basic heuristic level, CO2 adds something to the greenhouse effect, but also increases plant growth. Which effect dominates under our current conditions? Nobody knows for sure. And that's just the most basic heuristic; a really proper treatment would require a precision of economic modeling that we don't have.

The pollution from ash is easier to estimate, and that alone would make coal not competitive any more.

Yes, this I agree with.

 

[Rive]

Traditional power engineering thinks of physical facilities having a 40 year lifetime.

With that comes further problems. The actual buzz in Germany is the coal phase out with a date of 2038. By that time most (coal) power plants (and connected infrastructure) will exceed 40yrs of age, of course with some modernization/renovation involved - but still in good, working shape. The problem is the amount of compensation required to balance the forced phase-out.

Traditional economists expects value written-off by 30yrs, so some thinks no compensation should be paid at all. But will be the value of those working, fully functional plants will be zero?...

 

[anorlunda]

Traditional power engineering thinks of physical facilities having a 40 year lifetime.

With that comes further problems.

Quite correct. Early retirement brings financial disruption and it scares investors for future projects. We see evidence of that. New natural gas plants with a 30 year lifetime, are finding that prospective investors demand a 5 year ROI because of future uncertainty. That greatly increases the capital costs and it adds to rising prices for consumers.

To be fair, the original investors may fully depreciate a plant earlier than its expected lifetime. That makes writeoff date and planning for replacements semi-independent.

Threats of future restrictions, or taxes also spook investors and makes them demand very short time ROI. That is not only costly up front, it also changes the generation mix. Nuclear plants with long project and construction times, with many threatened government actions, and with long ROI, are particularly hard to sell to investors. Wind and solar farms can be built on shorter schedules and shorter ROI. If investors can return their money and profit with just 5 years of subsidies, they can plan to abandon the facilities after 5 years if things change.

Future planning is essential because of the critical need for reliable power, and because of long lead times on many projects. But unforeseen disruption can ruin plans, causing chaos. Chaos threatens the reliable and affordable supply of power, and promotes haste and crime. That is the main message of the article. chaos=bad.

 

[CWatters]

I was reading yesterday that in the USA more energy was generated from renewable sources than from coal for the first time. Ok so not a great milestone but something.

 

[OmCheeto]

I was reading yesterday that in the USA more energy was generated from renewable sources than from coal for the first time. Ok so not a great milestone but something.

Just moments ago I read;

"In CA[California], today, demand between ​

3:00-3:30 PM, 96% renewable (RE) ​

12:30 PM-5:30 PM, 91.2% RE ​

3-4 AM, 52.4% RE ​

1-6 AM, 51.3% RE ​

12 AM-5:30 PM, 72.3% RE"​

​

And this is only 2019, before proposed WWS (solar, offshore wind, storage) has been added​

This was in response to someone who commented;

"Sunny day, eh? Talk to me at 4am. In fact, how about if you publish the numbers for 3-4am?"​

Which was in response to;

​

"Wind-water-solar (#WWS) supplied more than 90% of the world's fifth-largest-economy's (#California's) electricity demand from 12:30-15:30 PM today, and all renewables supplied >90% from 10:55 AM - 16:00 PM.​

Seems like our infrastructure isn't as bad as I thought.

ps. This conversation took place yesterday.

​

​

 

[Jimster41]

Please please, fund me to do that simulation. That has been my wet dream for decades. Not just me, but lots of other engineers. There have been several attempts, but the problem is difficult. You simplify enough to make it practical, then the results are doubtful because of the simplifications. It lies somewhere between first principle physics and economics, and predicting future Dow Jones stock prices.

On good days I wake up thinking I go to work to help make it easier i.e cheaper for domain experts like yourself to do exactly that - real-time, live, etc. and to provide the means to draw that balance (maybe iteratively or adaptively) between gestalt and precision - given the wild uncertainty two steps out into the future "cone of probability".

I recently had a nice day where I was able to instantiate 2 complete 2x2on1 Combined Cycle plants in like two lines of script. This kind of capability makes the idea of setting up useful experiments with different generation portfolios (of real size)... at least more ballpark cost effective, at least plausible.

One of the issues with large simulations, at least in my experience... it's one thing to set up a big Design of Experiments (not trivial but sort of straightforward). It's another thing to be able to see what the heck you got once they have run. One thing we are working on, as are others I'm sure, is using empirical methods (ML) to summarize big complex data sets generated by some DOE smoking away on a cluster.

 

[essenmein]

Not if you assume that the effect of CO2 emissions is net negative, no. But I am also highly skeptical of that assumption. Just on the most basic heuristic level, CO2 adds something to the greenhouse effect, but also increases plant growth. Which effect dominates under our current conditions? Nobody knows for sure. And that's just the most basic heuristic; a really proper treatment would require a precision of economic modeling that we don't have.

The empirical evidence we face however is that it is a net negative. The CO2 thing is complicated, because its a complicated system. Yes plants like CO2, but we are deforesting, CO2 green house effect is small, but a tiny change in average temp changes teh vapour press of water, and that is the green house gas that basically controls the surface temp of our planet. Small change in CO2 results in a small uptick in temp and the resulting increased uptake of H2O does the rest.

Then, the problem isn't even the increase in temperature, geologically speaking the Earth is the coldest, barrenest its been in a while, prehistorically CO2 levels, temperatures etc were much higher and life prospered. The problem is the rate at which that change is happening. There is a part of me that wonders if we are underestimating the capacity of nature to adapt, so some species die, new ones thrive and eco systems change, but once things have adapted, then maybe things could be ok right?

 

[PeterDonis]

The empirical evidence we face however is that it is a net negative

It is? I thought it was generally agreed that it's not a net negative until global average temperatures get another couple of degrees higher. But even that is based on a lot of assumptions that are very uncertain. I don't think we understand the problem domain well enough to know what the current net impact of CO2 levels increasing is.

a tiny change in average temp changes teh vapour press of water

But it also changes the hydrologic cycle--increased temp generally means more evaporation, hence more clouds, hence more precipitation, which transports more heat from the surface to the upper atmosphere. This is shown as "latent heat transport" in the energy budget diagrams, but as far as I can tell we have a very poor understanding of how much that heat transport number increases with temperature. It wouldn't take much of an increase to offset the effect of more average water vapor in the atmosphere, so it seems like there's a lot of uncertainty here that we have no good way to decrease at present.

There is a part of me that wonders if we are underestimating the capacity of nature to adapt

I don't just wonder that we might be underestimating this, I think we almost certainly are underestimating this. Global average temperatures changed by something like 0.6 C during the 20th century--and what's more, it wasn't a linear change, there was early 20th century warming, followed by mid 20th century cooling, followed by late 20th century warming. We adapted through all of that. And over historic times humans have adapted to larger changes than that.

 

[mfb]

It is? I thought it was generally agreed that it's not a net negative until global average temperatures get another couple of degrees higher. But even that is based on a lot of assumptions that are very uncertain. I don't think we understand the problem domain well enough to know what the current net impact of CO2 levels increasing is.

Weather in many places has been getting more extreme already. We know the impact on coral reefs, we know the impact of rising sea levels and we know both will get worse. One million species are at risk of extinction and climate change is one of the important reasons. And so on. Meanwhile positive effects are very rare.
That is the current level. Even if we would stop all CO2 emissions tomorrow we would get a bit more warming, but a full stop tomorrow is purely hypothetical. We will see the temperatures rise more. How much? That depends on future emissions. Even if you think the changes so far don't matter at all and only future changes can be bad: Even then CO2 emissions have a net negative impact.

And over historic times humans have adapted to larger changes than that.

Over thousands of years, not within a generation. And with colder temperatures. xkcd has a graph.

 

[PeterDonis]

Meanwhile positive effects are very rare.

They're very rarely studied and talked about. But I don't think that means we know for sure that they're rare. For one thing, there should be an obvious positive impact on plant growth and therefore crop yields.

Over thousands of years, not within a generation

Multiple changes over thousands of years. It's not really possible to rule out fluctuations on short (roughly a century) time scales from the data, because the resolution of proxy data (even leaving aside all the other possible issues with it) is just not that good; it has error bars at least a degree wide and a time resolution that might not even be as short as a century.

Also, "within a generation" is too short even for the change that's happening now. We're talking a time scale of a century or so; that's multiple generations.

xkcd has a graph.

I don't think this qualifies as a valid source. I don't see a reference to an actual peer-reviewed paper.

In any case, I think we're getting off topic for this discussion (and also possibly pushing the boundaries of PF rules about climate change discussions). The original item that started this subthread was a carbon tax. I think @anorlunda summed that up well enough here:

I have no public pro/con position on carbon tax. I said only that it is less dangerous than putting a thumb on the market's scale.

I personally do not favor a carbon tax as a policy, for the reasons I've given, but I agree that it's less dangerous than putting a thumb on the market's scale. So if the only policy choices were carbon tax and thumb, I would pick the tax as less dangerous.

 

[essenmein]

The near future for installation of utility-scale PV is complicated because we expect many solar farms to be upgrading with new panels; perhaps once every 3 years. That partially re-uses existing installation investments. That is good, but makes forecasting more difficult.

How does this make sense? What is the energy ROI period for a solar panel?

If "greenness" is the goal, surely using something till EOL is far better than upgradeitis?

 

[anorlunda]

If "greenness" is the goal, surely using something till EOL is far better than upgradeitis?

That depends on the numbers obviously.

Being "prematurely obsoleted by new technology" is not unique to the power industry.

Some of us may still own AT&T rotary dial phones. They were built to last 45 years, but they
(and the later touch-tone phones) were obsoleted far in advance of their design lifetime. In phones, we are now so used to rapid obsolescence that the idea of designing a phone for 45 year life would be ludicrous. The same applies to PV panels in the modern world. A wise project manager considers upgrades during the lifetime of the project as foreseeable.

Haven't we rejected "greenness is the goal" several times already in this thread?

 

[essenmein]

Haven't we rejected "greenness is the goal" several times already in this thread?

It was rejected by some people, a rejection I don't agree with, mostly because it does not reflect discussions and motivations behind renewable push in the pubic sphere, this is almost entirely centered around climate change, at least from what I've seen/heard.

 

[anorlunda]

It was rejected by some people, a rejection I don't agree with, mostly because it does not reflect discussions and motivations behind renewable push in the pubic sphere, this is almost entirely centered around climate change, at least from what I've seen/heard.

You're entitled to your opinion. In #33 I said:

Solar PV and Wind power are wonderfully attractive technology. Not since Niagara Falls (hydro power) have we found something so close to free and unlimited sources. Carbon concerns aside, it would be foolish to not exploit those technologies as much as we can. So it is unnecessary to push carbon as a priority higher than keeping the lights on.

Solar and wind will be expanded and utilized ASAP with or without climate concerns. They continue to have competitive cost advantages that assure that they generate as much as practical without giving them any unfair advantages. With less confidence, I also believe that withdrawal of all subsidies, priorities, and preferences would not slow down the growth of renewables significantly.

So my opinion is that solar/wind have gotten a tremendous boost in attention because they are green, but now they are just attractive power generation technologies independent of their green qualities.

Also IMO, the goal is reliable and affordable power is the goal, green or brown. Without power, we loose the ability to move anything forward or make anything greener. We have forgotten how to run civilization without electric power.

 

[PeterDonis]

We have forgotten how to run civilization without electric power

I don't think it's just a matter of forgetting. Civilization as we have it now has added a lot of features that are only enabled by having ubiquitous electric power. (The medium by which we are having this conversation is one of those features.) Those features would have to be given up if we somehow lost all electric power, which doesn't seem like a very attractive option. But there is certainly much to be gained from figuring out how to still provide those same features but with less electric power, or at least less electric power that requires costly infrastructure to generate and distribute.

For example, even if solar panels on my roof can't always provide enough power by themselves to run my refrigerator and air conditioner, they probably can provide enough power to keep the batteries on every digital device in my house charged; and with not that much battery backup they can probably keep all of the LED light bulbs in my house (which is now every light bulb in my house) on for the times that we have them on. They might even be able, with not too much battery backup, be able to keep the LED TV on for the times that we have it on. Up to now we have just powered all that stuff using 120V AC outlets, with a lot of AC/DC converters attached to individual devices, because that was easy and cheap. But there might come a point where on net it is actually more cost effective to uncouple low power devices from that 120VAC grid.

 

[essenmein]

So my opinion is that solar/wind have gotten a tremendous boost in attention because they are green, but now they are just attractive power generation technologies independent of their green qualities.

Also IMO, the goal is reliable and affordable power is the goal, green or brown. Without power, we loose the ability to move anything forward or make anything greener. We have forgotten how to run civilization without electric power.

This seems contradictory to me, especially when viewed with the context of the article.

Your opening paragraph and the first sentence of the next:
"The electric power industry faces much turmoil in the coming decades. The business model of of the electric utility company (public or private) may not survive. In addition, the power needs of high density cities may diverge significantly from non-urban areas causing political turmoil and technical hurdles.

The increasing share of renewable energy will be a major factor in the turmoil."

Then you say:
"So my opinion is that solar/wind have gotten a tremendous boost in attention because they are green, but now they are just attractive power generation technologies independent of their green qualities. "

How can a power generation technology be so attractive when they are, as you yourself identified, a large threat to:
"Also IMO, the goal is reliable and affordable power, green or brown." (note removed duplication)

Your opening paragraph is basically saying in a nice way, that reliable, and therefore affordable power is being directly threatened by a select few "attractive generating technologies".

Which to me doesn't actually make them that attractive.

Consider this scenario:
You've changed your generation method to be purely hydro and nuclear, no wind, no solar (ie meeting the climate change requirements of zero carbon).

Does the problem outlined in your article exist?

 

[anorlunda]

This seems contradictory to me, especially when viewed with the context of the article.

Fair point. The thread is caused by the rate of change of new technology, and by the property of these two new sources that their marginal costs for the next MW are nearly zero.

I am neutral regarding all technologies that can service the grid. I do not advocate for or against any such technology. What I fear is chaos, or disruptive changes that threaten reliable affordable supply.

So I guess it does sound like a paradox. The attractiveness and low prices of solar/wind threaten to bring change so fast that chaos could result. I think I made the analogy of reupholstering the seats in your car while you drive down the highway. That does not mean new upholstery is bad.

 

[essenmein]

I think I made the analogy of reupholstering the seats in your car while you drive down the highway. That does not mean new upholstery is bad.

You did, the problem as I see it though is that society has convinced itself that the only way to reupholster a car is to do it while driving on a highway (intermittent renewable), when in reality the smart way is to pull into a workshop and get it done right, because let's face it, if done at highway speeds the workmanship, ie quality, will suffer.

We can solve this without causing chaos, so why pursue the chaotic route?

 

[CWatters]

Renewables continue to grow in the UK. Recent news is that the Britain has managed to go a week without burning coal for power generation, a first time this has happened for over 130 years...

https://edition.cnn.com/2019/05/09/health/uk-coal-electricity-renewables-health-scli-intl/index.html

 

[mfb]

The UK basically replaced coal by gas and a bit of renewables in the last 30 years. 40% of the electricity is produced from gas now. 20% nuclear power, 10% wind, 9% coal, 8% biomass, 3% solar, 1.5% hydro, 8% oil and other (data from 2016).

Only 13% renewables that depend on the weather.

I don't think this qualifies as a valid source. I don't see a reference to an actual peer-reviewed paper.

Check the right edge.
I agree that more discussion of that would be off-topic.

 

[PeterDonis]

Check the right edge.

Ah, got it. My sideways reading skills are a little rusty...

 

[anorlunda]

when in reality the smart way is to pull into a workshop and get it done right

What are you saying? It sounds like you want to have society sit in the dark during renovations.

 

[essenmein]

What are you saying? It sounds like you want to have society sit in the dark during renovations.

lol like all analogies, they fall apart if you ask to much of them!

There is no reason we can't change to clean reliable power without disruption.

I'm glad I'm not the only one that thinks so, and things are moving in this direction, just a little more out of the media spot light:

https://edmontonjournal.com/news/na...ctors-can-solve-canadas-climate-change-crises

 

[mfb]

The one big downside of nuclear power is the poor acceptance in the population - mainly coming from people who have no idea about the topic.

 

[CWatters]

The UK basically replaced coal by gas and a bit of renewables in the last 30 years. 40% of the electricity is produced from gas now. 20% nuclear power, 10% wind, 9% coal, 8% biomass, 3% solar, 1.5% hydro, 8% oil and other (data from 2016).

Only 13% renewables that depend on the weather.Check the right edge.

Things are changing very rapidly in the UK. One sources says that in 2018 around 33% of the UKs electricity generation came from renewable sources and in Q2 wind alone produced 37%.

Government data says renewable generating capacity increased 10% in 2018 alone. Think mostly offshore wind

 

[merriam]

To some degree, transmission lines can replace

Sorry to be slow to respond. I was very busy yesterday.Talk about risks. My article was so wordy that I'm afraid that not everyone read it to the end. Sure there are captital costs, fuel costs, maintenance, operating, marginal, average and more. But there are also multiple sources of revenues to the owners, not just kWh energy.

The energy market described in the article uses primarily marginal costs to determine the optimum, and it compensates the owners for their marginal operating costs.

The ICAP payments, directly compensate owners for their capital costs. To a lesser extent, so do payments for providers of reserves, frequency control, and voltage support. All of those payments are for capabilities, not for generating energy.

I think the debate in this thread about marginal costs was caused by an attempt to assign all types of costs on to one measure, one kWh of energy. That oversimplification ignores those other forms of revenue streams.

Those markets I described were designed by the actual participants. That means the people who buy and sell wholesale power. The designs are constantly tweaked. All those people, each looking out for their self interest assures that no source of value, goes unrewarded. But again, let me stress I speak of wholesale markets, not retail. They are transparent and open for scrutiny, but they seldom attract press attention because it is so difficult to relate what happens there to a consumer's monthly bill. Remember, I mention in the article wholesale prices change every 15 minutes, but rates charged to retail customers are set by law and typically stay constant for a year or more.You're correct, in southern California home rooftop solar has already grown to a very significant portion.

• Net metering, which is wildly popular among homeowners, is not sustainable if the portion of solar gets too large. With net metering, the PV owner is using the grid to provide the functionality of a Tesla Powerwall, but with someone else paying the costs. That's not sustainable at a large scale.
• Retail rate structures can be modified. Imagine a limiting case where every homeowner is self-sufficient for energy production, but they still want a grid connection for backup. There would be zero revenue to the utility for kWh charges. In that case, the obvious solution is to switch to a backup service monthly fee, and forget about kWh charges
• As you point out, there can be contradictions between the grids needs and various government mandates. That is what I mean by destabilizing factors. We can ignore them if the fraction is small, but as it gets larger we get forced to restructure, both technically and economically.
• There is one such restructuring movement underway in several states. That is to create a third layer. So called-agreggators form a buffer between retail consumers and the wholesale markets. The aggregator might offer "a deal" to say 1 million PV home owners, and represent the aggregate resource as a single wealthy and knoledgeable participant in the wholesale markets. I remain skeptical of this idea, but it is an attempt to bridge the transition between central power plant domination, to distributed consumer generation domination. (In the meantime, distribution engineers pull out their hair over protection against faults and short circuits, made complicated by distributed generation. That's a different domain than bulk power engineering.)
• If we take Russ' concerns to the extreme, then we need to revise the wholesale level to use something other than money to determine optimum. I mentioned that in the article, and I also mentioned my fears about such changes because of the risk of creating loopholes that allow cheating and stealing on a huge scale.

When tinkering with such critical things as the electric infrastructure, and hundreds of billions of dollars, the word prudence ranks extremely high in the minds of designers. But the prudence of central planning is hard to apply to a wild-west environment where every homeowner makes his independent decisions and who also lobbies his congressman.

I should also mention a huge factor the article doesn't address. How specifically are owners of power transmission lines compensated for their investments and services? That is even more abstract and difficult to understand than energy generators/consumers. It can also be big bucks, with up to $3 billion for each major new line. And with renewable advocates calling for 250K new miles of HVDC lines in America, and 500K new km in Europe, the magnitude of the transmission problem could itself become dominant.

In the article, I allude to political problems if the needs of high density cities diverge from everyone else. Distributed generation and high rise apartment buildings don't dance well with each other. In the USA, it is roughly a 50-50 split between people in single-family multi-family dwellings. That same split has a high correlation to red/blue political views which makes it even more volatile.

I love this topic precisely because it requires so many disciplines. Energy conservation, Ohms Law, economics, politics, cybersecurity. To me, it will never be boring.

To some degree, transmission lines can replace generating capacity or energy storage. The sun is always shining somewhere and transmission of power can overcome the dark. But transmission lines cost money and will usually charge for their use. Say something about other ways that utilities handle this - capacity charges, time of use charges, and special charges for anticipated high demand periods.

 

[Astronuc]

A relevant article from the UK with a perspective of off-shore wind and reduced grid inertia, which makes frequency control more difficult.

https://www.yahoo.com/news/britain-green-energy-disaster-awful-050000590.html

 

[russ_watters]

I was also thinking about this insight, as there has been a lot of reporting this spring about negative electricity prices in Europe due to oversupply:
https://reneweconomy.com.au/this-is...es-go-negative-as-springtime-renewables-soar/

Thoughts, @anorlunda ...?

 

[Fisherman199]

A relevant article from the UK with a perspective of off-shore wind and reduced grid inertia, which makes frequency control more difficult.

https://www.yahoo.com/news/britain-green-energy-disaster-awful-050000590.html

On a related note, many PPAs are in dispute for off-shore wind in NY area. procurements are state-sanctioned but build-outs just aren't economical. Firms are trying to renegotiate left and right.

 

[Fisherman199]

A relevant article from the UK with a perspective of off-shore wind and reduced grid inertia, which makes frequency control more difficult.

https://www.yahoo.com/news/britain-green-energy-disaster-awful-050000590.html

I'm not @anorlunda but I remember reading some moons ago that there were inversion technologies which solved the inertia question. Inertial signal can be essentially replicated on the grid level. That said, to my memory, I have not read in any interconnection study where this sort of technology has been requested or implemented.