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Comment by fwlr | Hacker News Reader

tl;dr Connecting new power generation to the electricity grid is a queue-based permit system that is stupid and slow, but simple and supremely stable. There is a decent chunk of renewable power “in the queue” but speeding up the connection process risks damaging stability.

The article notes India’s electrification as a partial counter-example: relatively fast, but correspondingly relatively unstable. (One marker mentioned was “kerosene liters consumed”, as a proxy for how much lighting has been replaced by electricity, they note the amount dropped from 9 billion liters to 2 billion liters, which I take as a very rough indicator of ~80% grid reliability - not even one “9“ of stability. It’s hard to find representative data on developed-world power grid reliability but for instance there is a common estimate that the average Australian resident experiences 200 minutes of power outage per year, which corresponds to somewhere above three-and-a-half 9s and below four 9s. This suggests potentially quite an extreme cost in stability for the moderate benefit of speeding up queue times for renewable power.)

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Grid stability is essentially a different thing than local power availability. You lose your power if a tree falls on your power line, or if your local transformer fails. Sad for you, but completely unrelated to grid stability.

Grid instability happens when load and supply are no longer matched. That's when serious things have to happen - load shedding and rolling blackouts. In the developed world we put a lot of money into avoiding this - pumped hydro, battery storage, fast response gas turbines, frequency control programs running with big industrial users, and (opt-in) load shedding of big industrial users. All so that power is available to an end user who needs it.

As someone living under PG&E, I'd love improvements to both. In the late summer we often lose power due to under-supply, in fall due to concern for fire, and in winter due to wind. In one recent month I was out of power for eight days in three tranches.

PG&E is an excellent example of grid failure through regulatory failure. California has made a mess of electrical regulation over the decades, and today you have to suffer through the result.

I split my blame with roughly 2/3 going to CPUC and the rest going to PG&E.

Yeah, like I said it’s really hard to find representative data on grid stability. Local power outages will definitely overestimate grid instability by a lot, but it’s not entirely unrelated, it should capture ~most of grid stability issues (it is a gross over-estimate because maybe like 1%-5% of the total local power outage experienced is due to grid instability). So maybe the electrical grid is more like 5 or 6 nines.

> "speeding up the connection process risks damaging stability"

The UK has transitioned to renewables perhaps faster than any other major economy in the past decade[1], yet has a very reliable and resilient grid[2].

[1] As recently as 2012, around 45% of the UK's electricity was generated from coal. Now it's almost zero, with the last coal power plants to close by 2025. In the same period, renewables have grown from <5% to over 40% of grid supply.

[2] "Five 9s" transmission system reliability of supply nationally in 2021-22: https://www.nationalgrideso.com/industry-information/industr...

Well. I suppose this stability is mostly thanks to (A) natural gas and (B) biomass, aka wood pellets being burnt in former coal power plants. Those two basically replaced the coal that was phased out.

See this plot:

https://ourworldindata.org/grapher/electricity-production-by...

Agree, the speed of transition has been quite fast. As you can see in the following plot the UK started out at a rather low level of renewables. At this relatively low level the transition is probably easier than at higher levels.

https://ourworldindata.org/grapher/share-of-electricity-prod...

I'd guess the real challenge with grid stability will become more visible when grids all over the world reach some 2/3..3/4 of renewables.

Good management must also be counted as a factor, I think. Whatever that entails.

I don't think that chart really makes your case since it's measuring total production and on a total production basis it simply isn't true that gas and biomass replaced coal.

If you pull that chart to its full timeline, over 200TWh of coal production existed, and it's essentially all gone now, but there isn't 200TWh of gas and biomass, in total they're maybe 140TWh. There is 60 TWh of wind power production.

Now, in terms of capacity for instantaneous power, the Combined Cycle Gas Turbine plants probably do add up to similar capacity to older coal plants which were phased out, at least very close, but it's pretty rare for all that generation to actually be needed - this chart doesn't really show that.

As to "transition" the countries which look "slower" on this chart are mostly using a lot of hydro, which is very different from wind or solar, as well as being readily available from the mid-20th century a point where solar and wind power were not really established options. So we're not talking about China having a bunch of wind turbines, then kicking back for a decade and only adding more recently, but instead their enormous country has hydro power, and now it also is adding wind turbines. The UK is a small island (and some other even smaller islands which are useful for wind but don't produce hydro power) and doesn't have vast majestic water bodies like Lake Mead, so hydro power has always been a tiny niche here, and that's all you're really looking at.

> If you pull that chart to its full timeline, over 200TWh of coal production existed, and it's essentially all gone now, but there isn't 200TWh of gas and biomass, in total they're maybe 140TWh. There is 60 TWh of wind power production.

Indeed, if you view the whole chart, the development during the 90s directly supports my claim I'd say.

https://ourworldindata.org/grapher/electricity-production-by...

But still, I guess I phrased my actual point rather poorly. True, wind and solar produced almost 1/3 of the UK's total electricity over the last 12 months, but what kept the grid stable was mostly natural gas.

In this role natural gas replaced coal.

> Now, in terms of capacity for instantaneous power, the Combined Cycle Gas Turbine plants probably do add up to similar capacity to older coal plants which were phased out, at least very close, but it's pretty rare for all that generation to actually be needed - this chart doesn't really show that.

Yes, pretty rare. But this is exactly what grid stability is about. Making sure the lights stay on even though it's cold and there's no wind. As for example end of November 2022 till middle of December:

https://www.electricinsights.co.uk/#/dashboard?period=1-mont...

Hydroelectric power was pretty widely available by the late 19th century.

Another interesting example is Southern Australia. It also went from coal to renewables, and also with gas as "backup". Its just fascinating how far they have come, from less than 1% renewables in 2007 to more than 60%, all without any hydro which makes reneables "easy".

https://www.solarquotes.com.au/blog/sa-renewables-milestone/

> "I suppose this stability is mostly thanks to (A) natural gas and (B) biomass, aka wood pellets being burnt in former coal power plants. Those two basically replaced the coal that was phased out."

Actually, most of the coal has been replaced by wind and solar. Biomass is not really that significant: it's only around 5% of the UK's grid supply, compared to over 30% for wind and solar. New biomass plants are no longer considered renewable in the UK so it's unlikely to increase in the future.

Not sure what data your chart is based on, but it's wrong, at least for biomass. See here for some up-to-date data (you can use the controls at the top to see different periods and historic data): https://www.electricinsights.co.uk/#/dashboard

Natural gas is still the largest single contributor to the UK's grid supply, but it's in decline, and will be overtaken by renewables in the coming years. Wind capacity will triple in the UK by 2030!

Imports have also increased in recent years as new HVDC interconnects have been brought online.

> Actually, most of the coal has been replaced by wind and solar. Biomass is not really that significant: it's only around 5% of the UK's grid supply, compared to over 30% for wind and solar.

True. By electricity produced natural gas and biomass have not replaced all TWh that formerly came from coal. (Even though you can see how natural gas directly replaced coal during the 90s here: https://ourworldindata.org/grapher/electricity-production-by... )

The point I intended to make is: there's two kinds of electricity production capacity. There's Flexible/dispatchable capacity such as gas, coal and others. And there's intermittent capacity such as solar and wind.

Without electrical storage (almost non existent), solar and wind cannot replace dispatchable capacity in the context of grid stability.

The increase in electricity produced from natural gas and biomass is what directly contributed to the grid remaining stable, _despite_ the increased production from wind and solar.

> Natural gas is still the largest single contributor to the UK's grid supply, but it's in decline, and will be overtaken by renewables in the coming years. Wind capacity will triple in the UK by 2030!

Yes. But it won't be the wind, that'll be keeping the grid stable, that's for sure.

Natural gas did partly replace coal during the 1990s, but renewables (mostly wind) is replacing natural gas today.

An increase in production from natural gas isn't needed to keep the grid stable. It just needs to be available for when supply falls short due to weather conditions.

The interconnections are also a big part of the solution: excess wind energy can be exported when it's plentiful, and imported (along with hydro, nuclear) from other countries when UK weather is unfavourable. It's always windy somewhere!

> "But it won't be the wind, that'll be keeping the grid stable, that's for sure."

No, but it will greatly reduce emissions, and improve energy self-sufficiency, security of supply and stability of prices when external events (like the Russia-Ukraine war) disrupt the market.

> Well. I suppose this stability is mostly thanks to (A) natural gas and (B) biomass, aka wood pellets being burnt in former coal power plants. Those two basically replaced the coal that was phased out.

More like a little under half due to those. From the plot at ourworldindata, expanded to start at 2012 since that is when the comment above was talking about, here are the changes in TWh contribution:

  -137 Coal
   -23 Nuclear
     0 Other renewables
     1 Hydro
     3 Oil
    11 Solar
    24 Gas
    24 Bioenergy
    45 Wind

This data does not seem consistent with other sources. There are no active oil-fired power plants in the UK, for example, and there hasn't been for a long time. (There are some that were built as oil-fired plants but were later converted to natural gas CCGT)

ourworldindata also seems to be overstating bioenergy by a huge margin. According to reliable sources[1], biomass supplied 20.83 TWh in 2021, not 39.11 TWh. I'm not sure what difference in methodology could account for such a big variance?

[1] https://www.electricinsights.co.uk/#/dashboard?period=1-year...

Interestingly enough, Tesla just released their "Master Plan 3" which admits the need for hydrogen for seasonal energy storage and synthetic fuels. It doesn't admit the need for nuclear though. So we can see it as a first step to coming to reality, but it is not there yet.

I bring this up because I am constantly annoyed by those who really haven't thought through their green energy dreams, and forget that compromises need to exist. These compromises actually have no serious penalties whatsoever BTW, it just requires a more complexity thinking process.

And in this case, it means that there will be a lot of times where the solution is to build a gas turbine running on hydrogen, ammonia, synthetic fuels, etc., or build a nuclear reactor. Just piling up more and more renewables onto the grid isn't a solution. We are finally seeing some people come to reality on this, and I expect even further shifts to more realistic thinking in the future.

> These compromises actually have no serious penalties whatsoever BTW, it just requires a more complexity thinking process.

Not entirely true, storage does cost money:

https://www.energy.gov/sites/default/files/2019/07/f65/Stora...

That said, as the tables in that report indicate its quite a complex topic.

(By my back of the envelope maths switching UK to fully wind and storage would triple electricity prices)

Relative to the alternatives, it does not cost more money. You just need to accept the existence of hydrogen-based energy storage and perhaps synthetic fuels too. Cost will be the same or less as other energy storage ideas. And if you accept nuclear, you don’t even need much energy storage at all.

Also, a big chunk of the “energy storage” solution is utilizing biofuels. Like in Germany where wood burning power plants are seen as green (hint: they’re not). Getting rid of this will be a huge boon. The compromise in question will have significant environmental benefits. It’s unfortunate that so many are blind to their own bad ideas and have not noticed the problems of biofuels.

I encourage you to do the maths on this a write it up in a blog post, it'll be enlightening :)

Every back of the envelope calculation of this makes the same basic mistake of acting like every watt is sacred and that spending billions on barely used batteries to save 1 Watt every 5 years makes sense.

It's just silliness disguised with maths. Which is excusable the first 10 or so times its done, but is getting old now.

What's really getting old is claiming renewables are cheap and easy to build while not calculating all the additional requirements that are needed to have a stable power supply such as overbuilding, storage etc.

That is a fair point, but what are you actually advocating for?

Tainting public perception of renewables with cost-related FUD more strongly?

IMO the need for storage and better grid connectivity gets brought up in every discussion about electromobility and renewable power already anyway, so everyone seems well enough aware of it.

I'd also like to point out that glossing over this is SUPER comparable with assuming >80% capacity factors for nuclear plants which the anti-renewable crowd always eagerly does.

> Tainting public perception of renewables with cost-related FUD more strongly?

Or maybe bring actual discussions into public perception, and not just the unquestioned undebatable "renewable everything will solve everything by magic"?

> so everyone seems well enough aware of it.

Of course very few are aware of it.

All the discussion is doe-eyed "we just need to replace everything with renewables". No one talks about the need to overbuild, and how much. Storage is assumed a solved issue even though it's not anywhere near the required scale.

They might be aware of it, but actual data is always useful.

Electrification, not renewables, is the problem to solve that requires major thinking outside the box. Your faster horses won't get us there.

The compromise is going beyond electrification. You need large scale energy storage or baseload power, plus the needs of industry (aka the hard decarbonization sector). This cannot be solved purely by electrification. People who have thought hard about the problem have realized this. Unfortunately, quite a few people are trapping in an obsession with ideological purity and haven't figured it out. Breaking this obsession has basically no negative consequences, as it simply gives you a real path to zero emissions.

The kerosene they are talking about was for burning in backup generators, not lamps.

Grid power dwarfed that produced by local generators even when it was 9 billion litres. 80% stability isn't the right conclusion from this.

Centralized grid instability is not going to stop new power generation from coming online. Decentralized power generation is what's already happening in countries with inadequate grids. People install batteries, solar, wind mills, generators etc. Anything they can do to mitigate against loss of power or unacceptably high prices for power. The more unstable the grid is, the more people do this. Just look at most of the developing world. There are lots of countries that never had much of a functioning grid where economic growth is creating demand that cannot be met by their electricity grid. In most of these places, people just go ahead and fix things themselves. And that increasingly means solar panels and batteries rather than expensive to operate generators.

In the UK, and elsewhere, there are a lot of home owners that have solar on their roofs. The reason is not power outages but electricity prices. And with recent price spikes, more people are considering doing that all over the world. The whole assumption that most new generation has to come from the grid is increasingly less true. Both companies and consumers invest in cheaper private power generation. Especially companies have a big incentive to reduce their cost. The more power they need, the bigger the potential savings. And of course increased demand with a limited supply creates price spikes as well. We saw that in the last few years. This just speeds up the decentralization.

Australia is a good example. About a third of the houses have solar panels already and the building codes are being updated to require solar panels for new construction and renovation projects. Millions of house holds generating tens of kwh every day is adding up to a lot of power. And a lot of it goes straight into the grid as well. Which adds to the instability. Lots more will be coming online in the next few years.

Rural Canada is also a good example. The grid is horrendously bad and it is pretty easy to outperform the grid reliability wise with a local solar/wind/battery setup. You might even go off-grid completely assuming a large enough battery and maybe a backup generator just in case.

The average outage time per year in Germany, as far as I remember, is below 2min. The uptime of my non-USV-backed server at home supports that, but that’s only anecdotal data.

Fellow German here, I’ve experienced a total of ~2 hours, in one single outage, about 20 years ago. Not even a single brownout since.

In my experience, USVs can make the uptime worse in Germany. The hardware is likely to fail before the next blackout.

According to tennet.eu (the grid operator for the Netherlands and parts of Germany), the uptime for their high voltage grid is about 99.99963%. Obviously it will be lower for individual consumers, since there is a lower voltage grid in between them and the high voltage grid that might fail separately. Still, I think I've personally experienced only one power failure in the last 5 years or so.

The only power cut I've experienced since I've been in the UK (8 years) was about 30 seconds long. By the time the operator had sent me an SMS about it, it was already back up. This is despite the UK's rapid transition to renewables. There was a fairly major power cut by our standards in 2019, but it didn't affect me.

Personally speaking, power cuts are so rare and short that I don't think about them or plan for them.

Here in South Africa the power can be off for anything from 2h to 8h a day and given the regularity of that interruption I've since gotten an inverter (with batteries) as well as several battery powered emergency lights to power me through. I know that many residents of India do something similar, and so I'm a little skeptical of this kerosene marker.

A honest, but offtopic question (if Dang sees it fit to remove, let him do it...): why do you stay in SA at all?

What are the redeeming qualities of the country, aside from the nature, which is fabulous?

If you are white, aren't you afraid of a possible pogrom against your family?

I'm not OP but it's incredibly hard to immigrate and as older people are less mobile/flexible it may mean leaving your elderly parents/grandparents behind, as well as your native culture and language and everyone/everything/everywhere you know.

I am thinking about leaving SA - the usual factors of cost, family, and change apply.

Redeeming qualities: I do have pretty good buying power in SA, the weather is great,and it is quite a multicultural place with friendly people by and large.

To my knowledge the rate of black on black violent crime is higher than black on white crime - SA has a general problem of violent crime. Its definitely a problem but a pogrom specifically is not a chief concern for me.

Thank you for an interesting reply. I come from a fairly safe country, so I cannot really imagine how living in an unsafe country looks like.

What precautions do people in SA need to take when travelling? Is there any sort of constantly updated "off-limits area map", or is it just common knowledge?

How does security in wealthier neighbourhoods look like?

Is hiking in the wild risky? Is public transport generally to be avoided, or are there "better and worse" services?

As far as electricity blackouts go, everyone has a generator, right? Is there never a shortage of diesel for those generators? What about the pollution that comes from running generators several hours a day?

> Is there any sort of constantly updated "off-limits area map", or is it just common knowledge?

No maps - just common local knowledge. Some areas you avoid completely, some you just avoiding walking or driving through late at night.

> How does security in wealthier neighbourhoods look like?

Most new higher-end developments are fenced-off security complexes - electric fencing all around, and 24/7 security services. But there are still many "regular" suburbs without that. In those you typically have security patrols, and individual houses may or may not have electric fencing, depending on the area.

> Is hiking in the wild risky?

Depends on the area. In some areas you just avoid hiking alone. The more remote areas typically have no safety issues.

> Is public transport generally to be avoided, or are there "better and worse" services?

Most (but not all) wealthy people avoid local public transport ("taxis" and trains) - they do have safety (and reliability) issues. There are good options in some places - e.g. a high-end train in Johannesburg & Pretoria, and Uber is a decent option in most cities. Long distance busses and trains are also typically fine.

> As far as electricity blackouts go, everyone has a generator, right?

No, generators are mostly only by businesses. Too noisy and too much effort to use for most residences.

The cheap solutions involve getting a mini backup power supply for your internet router, and some battery-operated lights. That + some planning around e.g. cooking gets you through most outages.

Recently, battery backup + solar became very popular for everyone who can afford it. Prices for solar and batteries dropped substantially over the last 5-10 years, and the entire installed system costs around 1/3rd of what you'd pay in the US.

> Is there never a shortage of diesel for those generators?

We've had one shortage that I remember over the last couple of years. It's much more relevant for vehicle fuel than generators.

> What about the pollution that comes from running generators several hours a day?

Much less than that of cars and our coal power stations. Noise is the biggest issue.

"Most new higher-end developments are fenced-off security complexes"

Thank you for taking time to write such a detailed answer.

The security complex thing, I wouldn't be able to live like that. It is my natural instinct to roam cities on foot, walk through the streets and the parks, observe people and birds etc., regardless whether it is my own city or a city that I visited as a tourist. But it seems this is precisely the one thing you can't do in SA safely.

Living behind a high wall, I would feel like an expensive prisoner. But maybe I wouldn't miss the freedom to roam, if I never experienced it in my life.

Yes, that's also why I don't live in a security complex. Many people don't, but there are many people who just want that extra safety factor.

Also, the higher-end security estates are massive - you effectively have your own park (or golf course) in the estate, so that may lessen some of that. Those places are expensive, but probably still much less than a comparable house in the US or Europe.

And in cities there are places where it's safe enough to just walk around like you mentioned, but safety is something that's typically on your mind wherever you go.

But not being able to just go where I want without considering safety, and not having my kids being able to just walk around or use public transport without fearing their safety - that is a big factor in making me consider emigrating.

The only safety conversation I remember having with our kids was about how to behave when pulled over by cops - in US.

I am sure we discussed how and where to go when they went to NYC, and that usually with friends some of whom are familiar.

Traveling wise I think it is common knowledge where the more unsafe areas are. There is always some overhanging tension living in SA, particularly in the more urban areas.

Middle class and up households often pay private security companies who patrol suburbs in branded hatchbacks and respond to alarms, etc. Robberies still happen regularly, but it helps. Complexes and gated communities are also more common. Almost all windows on houses are barred and people have security gates for their doors, and many properties have high fences, alarm systems, etc. (which don't really work because of the power problems but c'est la vie).

Hiking wise: it depends on the area and how many other people are hiking I think. I think that also applies to walking around generally.

Some households and businesses have generators, but they don't provide a high quality current, are noisy, and require diesel. Other places have inverters and batteries (like me) which charge during off-peak hours and act like a UPS when the power goes off. Quite a few households are going with solar roofs with an inverter and battery. All these things are fairly pricey even for middle class families, and quite a large percentage of the population is quite poor - so I don't think most people do have a good solution - but internet services are fully battery backed at least and many people have gas power for cooking (which helps).

Quite a substantial part of the SA grid is backed by diesel - it is worth bearing in mind that we are geopolitically quite "neutral" and still do business with Russia (who are a trade partner under BRICS - south africa is the S). Air pollution here is higher than in most US cities I think but not as bad as some other developing nations.

I've spent some time in Panama in one of those gated communities and it always felt like an 'inside-out' prison to me.

Even in developed countries I've noticed a marked difference (albeit nowhere near reported SA or India levels) when moving from Israel to Austria and then to Germany.

When I was growing up in Israel (1983-2005) power outages were common but not frequent (once every few months, my parents had a permanent supply emergency lighting, flashlights and candles at home for when the power would go out, usually for just an hour or 2).

Ever since moving to Austria (2005) and then Germany (2013) I think I have only once or twice experienced power outages and they only lasted a few minutes. So probably >20x less common (once a decade instead of a couple times per year) while also getting fixed a lot quicker. I don't know how much the infrastructure has improved in Israel since (I would guess it's better now but not as good as in Austria and Germany) but even back then it was still just an occasional nuisance unlike in the developing world where it happens enough to really impact people lives and productivity.

If I understand correctly there's little slack in transmission capacity to service new supply, and that new transmission infra isn't built out until new generation is queued. What wasn't clear to me is if construction of the new generation has to be completed before it can be enqueued or if e.g. completed permitting is sufficient.

Anyone significant planning on new generation will also plan the interconnect at the same time, and that includes transmission capacity. There is no point in having your new generation completed if the interconnect isn't done. In fact the bank shouldn't (and probably is checking, though not always) let you get financing for the new generation if you have not verified that there is interconnect to use that generation. Thus plans for transmission is supposed to happen before you get to permits. Though depending on timelines you may start building on before the other.

You putting solar on your roof is not significant. Your whole neighborhood putting solar up should be significant, but odds are this is done by individuals who don't realize their collective action is significant.

I think reliability should be divided up in different ways.

Their is "how well the moving bits are moving" which is different than "lines getting knocked down by acts of nature".

So, for example, I live in Seattle. Our power generation is quite reliable, but trees falling down during wind storms and knocking out power lines is also reliable, gravity being what it is.

I don't consider the Seattle grid to be unreliable, though I do acknowledge that digging up the entire city and burying power lines would, at great expense, prevent nearly all power outages.

But that sort of unreliability feels different than brown outs.

My utility concluded that between underground animals chewing wires, idiots with backhoes not locating before digging, and the extra time effort to repair burred lines: overall overhead wires are more reliable than underground. Note that they put a lot of effort into tree trimming near their overhead wires, which made trees falling on them was a rare problem.

Kerosene was subsidised heavily as it was used for cooking stoves widely.

At some point kerosene subsidy was removed and people shifted to battery based backup systems/ lights etc.

Electricity is unstable in large parts is my experience.

> One marker mentioned was “kerosene liters consumed”, as a proxy for how much lighting has been replaced by electricity, they note the amount dropped from 9 billion liters to 2 billion liters, which I take as a very rough indicator of ~80% grid reliability

I don't think those are related at all. Someone without electrical infrastructure running to their village is going to burn fuel regardless of how reliable the grid would be.

If you want to really analyze this you have to look at outage distributions (both size and duration). High voltage line disconnecting and leaving half a city in the dark for an hour is weighted-outage-time equal to one town sitting without heating for a week. However, it would be quite hard to call such disconnections equal.

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