Renewable energy means more mains outages?

No - there are plenty of multi Mega-watt and multi Mega-watt-hour battery/inverter installations going in around the world - Australia especially - and these provide grid support, voltage and freq stabilisation, VAR's and real power from minutes to hours for some of them - they can store excess solar during the day and provide grid support at night.

I would say exactly the opposite - many small generators distributed around the grid should buy a degree of redundancy if any part fails.

The problem as I see it is each generator has to be frequency and phase synchronized to all the others if their outputs are effectively in parallel. Conventional grid-tied systems spend around 3 minutes in sync mode before enabling their outputs and they disconnect as soon as some discrepancy is found. that works fine if you are augmenting an existing stable supply but if all the systems start trying to sync to each other there could be chaos. To the best of my knowledge there isn't a 'reference' 50/60Hz signal available that all generators can use.

Brian.

It depends. As long as the contribution of renewable energy, which is relatively unpredictable (both in time and quantity), remains small, there should not be much problem. It has been working so far because we can control supply and have some predictable idea about demand. When we introduce a number of large capacity supplies that are unpredictable (both in time and quantity) into the grid, the management could be much more difficult and you can expect more of load shedding (local effects) that are unpredictable. However, if you introduce small sources (many small supplies and they are locally synchronized, say most are up during day and all are down during night) then it may even introduce a sense of robustness in the grid because now the supply is more predictable.

Thanks, three very interesting answers.
I must admit though, it makes me wonder , from what you say, whether outages will end up manifesting.....unless we have enough of Easy Peasy's "Battery power stations" to put a "foundation" 50 Hz power waveform into the grid so that Betwixt's interesting "lack of snchronisation" effect doesnt happen.

Australia has loads of solar to top up these battery stations, but i actually wonder in places where they dont or cant have these battery stations, that mains outages may actually occur.
Thanks to C_Mitra also, you seem to suggest that there wont be outages as long as renewables are a small percentage of the total.....but i suspect that renewables will end up being the biggest contributor, and if it means mains outages, ....then its tough luck......The march of the Great Thunberg is very powerful, and obviosuly has the support of the "powers that be".

I suspect if renewables cant be backed up with battery stations, then they wont be...and mains outages will be common.....we will be told its tough luck...its better than the world getting flooded due to greenhouse effect.

Sooo... renewables
As there are more and more electric vehicles on roads, there is a bigger problem: infrastructure in cities, and specially in rural areas, as the EVs are power hungry while fast charging.

Exactly.....i think mains outages could be with us....in places where the battery stations dont exist..

I beleive that the "powers that be" are going to cease coal/oil and nuclear stations...and have renewables...and if it means mains outages for a couple of minutes each and every day....then they will say thats ok. ..Trouble is, it means mains connected power supplies, which are permanently connected to the mains, and would normally only ever experience inrush once in their lives...will now experience inrush each and every day......and they probably have NTCs and inrush resistors which aren't rated to suffer this every day.

I wouldn't worry. The diversity and distribution of generators in the grid should take care of everything and there are still plenty of 'standby' and hydro generators to fill in the gaps in the unlikely event of local brown outs. We have a 'standby' hydro generator near here that can run to MW levels in a few minutes and there are plans for several micro nuclear generators too.

If you think surge limiters are vulnerable you should move to my location. I haven't had one fail in 20+ years and power reaches me along 40 miles of overheads from the nearest power station. Local failure is quite common and of course the risk of lightning strikes over that distance and through mountains is high.

Brian.

cupoftea said:

I beleive that the "powers that be" are going to cease coal/oil and nuclear stations

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Bolded is "clean" contrary to coal/oil/gas

If you think surge limiters are vulnerable you should move to my location. I haven't had one fail in 20+ years and power reaches me along 40 miles of overheads from the nearest power station.

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...Thanks, though i would believe it that you have spec'd up a very good surge generator for your property. Whereas many cheap offline PSUs wont have that kind of thing.
Also, i dont think Hydro is common away from Wales/Sctoland in UK, and micro nuclear generators, ...to be honest, i would rather have renewables that had outages for a few mins each day than micro-nuclear stations. For one thing, the UK cant make its own nuclear, UK seems to rely on other countries to do it.
To be honest, i dont see a great long term problem with commercial office and domestic power going off for a few mins each day. Industry could have its own "reliable grid".

ZASto said:

Bolded is "clean" contrary to coal/oil/gas

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Is it really true?

Consider the amount of cement (concrete) used in the construction of the plant. The mining activity in getting the fission material. The energy used in the isotope enhancement (enrichment). And the processing of the waste. And the waste disposal.

Surely it is very clean once the plant has been constructed and you count only the CO2 contribution as the real measure of cleanliness.

I often wonder why the established technologies (coal, nuclear etc) produce electricity at a higher cost compared to an upstart technology like solar. Well, solar energy is cheap thanks to the Chinese!

The 'clean' aspect of micro nuclear comes from the longevity of the construction. It is true that vast amounts of CO2 are produced in the building of major power production but spread over say 40 years of operational life the amount per year is relatively low and much less than burning fossil fuel would produce.


Nevertheless, the risk of power loss because:
1. it hasn't rained in months so hydro schemes can't operate,
2. there is no wind over the country,
3. the sea tides have ceased (moon gone out of orbit!),
4. it's night time.

all coinciding, is pretty slim.

Brian.

betwixt said:

The 'clean' aspect of micro nuclear comes from the longevity of the construction. It is true that vast amounts of CO2 are produced in the building of major power production but spread over say 40 years of operational life the amount per year is relatively low and much less than burning fossil fuel would produce.

Rolls-Royce plans 16 mini-nuclear plants for UK

The firm says the project will create 6,000 new jobs in the Midlands and the North of England

www.bbc.co.uk

Nevertheless, the risk of power loss because:
1. it hasn't rained in months so hydro schemes can't operate,
2. there is no wind over the country,
3. the sea tides have ceased (moon gone out of orbit!),
4. it's night time.

all coinciding, is pretty slim.

Brian.

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India had the first power plant (nuclear) in 1969; it produced 160MW of power but was often shut down (I do not know the reasons then). Perhaps this will come under a mini class. This is still running, it was down for several years due to sanctions but take a look at the column "energy availability factor" (whatever that may mean) in the official reference: https://pris.iaea.org/PRIS/CountryStatistics/ReactorDetails.aspx?current=285.

One thing is for sure: it has created enormous employment. All employees living on site get free electricity, even when the plant is down. The diesel generator it uses is impressive in size.

When I was younger (that was a long time back) I joined a protest march in Lund (in Sweden) against the local nuclear power plant that produced 2X500MW of power and was still looking for customers.

There are nuclear power plants that produce 1-5MW of power (nano size), come fully assembled and costs slightly more than an arm and a leg. I first sighted one on you-tube but this one is real: https://www.energy.gov/ne/articles/what-nuclear-microreactor

But I digress. Nuclear energy is not renewable.

Nevertheless, the risk of power loss because:
1. it hasn't rained in months so hydro schemes can't operate,
2. there is no wind over the country,
3. the sea tides have ceased (moon gone out of orbit!),
4. it's night time.

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Thanks, but Hydro and tidal energy isnt available away from mountains and most coastlines.
(Tidal is very little used anywhere)
So that leaves wind and solar....and theres a high chance neither of them will be available simultaneously.

So i have to say i do think that daily mains outages are a potential reality.

"Renewables are bad for the grid" is a talking point sometimes heard in the USA. In particular, after the widespread power outages in Texas last winter, many politicians immediately blamed everything on renewable energy. Of course, it turned out later that failures in fossil fuel plants accounted for twice as much lost generation as renewables. Similarly, in California last year, renewables were a scapegoat for rolling blackouts, but in reality it was much more about prolonged heat waves causing unprecedented energy demand, and also constrained transmission capacity due to wildfires (caused by that same heat wave).

I'm not aware of any clear cut cases of blackouts being caused by intermittent renewable sources. Failure transmission systems or non-renewable generation has always been a key factor. Adding more renewables to the grid cannot, by itself, lead to blackouts. Disabling more reliable baseload/peaking sources can definitely lead to blackouts, but that's entirely independent from how much renewable capacity is present. So anybody claiming that renewables cause blackouts is just spouting nonsense.


The assassination of nuclear energy is an absolute travesty. Nuclear is at least as safe as solar/wind, same lifecycle CO2 footprint as solar (better than wind), and is capable of providing reliable baseload (unlike wind and solar). Research reactor designs can even throttle their output as quickly as gas plants. Waste storage is a non-issue, in a technical sense. Nuclear is close to an ideal energy source, and the fact that it's opposed by self-identified environmentalists is absolutely maddening.

Thanks to sensational coverage of nuclear disasters, everybody knows about Chernobyl, which was truly an engineering disaster of immense magnitude. But how many of them have heard of the Banqiao Dam disaster, whose death toll was a thousand times higher?

Thanks, interesting, but i hear that the waste from nuclear is a problem. Admittedly that was Clive Bull on LBC radio.
But anyway....i agree with you that as long as the main brunt is taken by oil/coal/nuke etc, then we wont get blackouts...but in future...that will all be gone, and we will just be provided for by wind and solar....and you seem to agree that that can mean more outages.

Hi,

Renewables are not bad. In most cases they are good for the environment.
But you can't rely on them. They can't work without other sources of electrical energy.
Good thing: We know about the problem, thus we can react on it.

We know that in some regions there is wind and the sun is bright. We know about winter and summer, day and night.
We know that they can't provide "energy on demand", we know that they are not very suitable to stabilize mains frequency.
Knowing the enemy is the best way to handle it.

Nuclear plants give a huge amount of energy, but is very slow to control. Faster are coal power stations, hydraulic power stations, diesel engines, battery operated systems. All have their benefits and drawbacks.
Solar and wind energy is not good to control. Thus one can not use them without other energy sources that are good to be controlled

Klaus

KlausST said:

Knowing the enemy is the best way to handle it.

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I agree and we know that we cannot have solar supply at night and we need to make contingency plan for that. Perhaps we need to run big industries during daytime only and let nights be passed in silence.

But I do not see thermal power stations going out of business very soon. I believe Germany has shut down all nuclear power plants. On the other hand, I hear that France has shut down all coal mines. And both are doing rather well.

But in developing countries we still do not know the enemy; we are forced to do shadow boxing.

Hi,

Germany has not yet shut down all nuclear plants, but they plan this for the next few years. Let´s see how it works.
This should pretend that Germany does not use electrical energy from nuclear plants. But there is a huge European grid. And we sell and buy ;-) electrical energy from other countries.
We definitely buy from countries with a lot of nuclear power plants.

Latest statistics say we (Germany) produce energy:
* 35% renewables
* 23% coal
* 12% nuclear
this makes 70%. I don´t know about the missing 30%.

****
Electrical cars don´t need petrol...but they are no perpetuum mobiles. Wihtout saying they are good or bad... they need energy. And this energy needs to be produced and transferred.

The next decades will be a challenge.

Klaus

cupoftea said:

Thanks, interesting, but i hear that the waste from nuclear is a problem.

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It is not, at least in places with sensible policy. France is the model for managing the nuclear fuel cycle. They recycle the majority of their "spent" fuel. The small remainder that can't be recycled is stored on the surface or deep underground. Incredibly, in the US, recycling fuel is outright banned for commercial reactors. Many states have passed laws banning storage of nuclear waste purely due to NIMBYism. Waste has become a "problem" in some places because sensible fuel cycle practices have literally been banned.

Fun fact: Coal fired power plants release more radioactive waste than nuclear plants (per MWhr of generation). This is true even if you include all nuclear accidents in the data. But for coal, releasing radioactive waste isn't even considered an accident (and thus they don't even bother to track it), it's part of their normal fuel cycle.

Nuclear energy is just one of those subjects where people's beliefs are completely contrary to science.

cupoftea said:

But anyway....i agree with you that as long as the main brunt is taken by oil/coal/nuke etc, then we wont get blackouts...but in future...that will all be gone, and we will just be provided for by wind and solar....and you seem to agree that that can mean more outages.

Click to expand...

Yeah, if you suddenly switched off all non-renewable sources, you'd have a lot of problems. Nobody is actually suggesting we do that, though. So I'm not sure what point you're trying to make.

KlausST said:

Germany has not yet shut down all nuclear plants, but they plan this for the next few years. Let´s see how it works.
This should pretend that Germany does not use electrical energy from nuclear plants. But there is a huge European grid. And we sell and buy ;-) electrical energy from other countries.
We definitely buy from countries with a lot of nuclear power plants.

Click to expand...

Yes, it's important to consider energy imports, not just production.

Germany's domestic energy production, in a vacuum, looks pretty good:



However, Germany imports most of its energy. Here's the breakdown of energy consumption in Germany, by source.



It's particularly bizarre that Germany categorizes biomass (basically burning wood) as renewable. But biomass is a CO2 polluter just like fossil fuels. Green renewables (hydro, wind, solar) account for less than 10% of their consumption. Because they're phasing out their nuclear fleet, representation of low-carbon energy sources has recently decreased, overall. The lost generation of nuclear is compensated almost entirely with gas imported from Russia via Nordstream.

Even so, Germany is commonly perceived as the darling of green energy policy. Overall their emissions have decreased recently, but that is mainly due to overall energy consumption falling (especially due to the pandemic). German energy policy regarding renewables has little to do with it (but they are definitely related to the high electricity prices in Germany).