Future fuel sources

[aro]

3 hours ago, turboplanner said:

Would it really be an issue if we do reach the magic 1.5 degree increase in temperature?

Would we be worried if Melbourne gets the average temperature of Sydney, Sydney gets the averaage temperature of Brisbane and large areas of norther deserts become tropical and available for living and farming?

That's not how it works. 1.5 degrees is the average over the globe, not what is experienced in particular locations.

 

Weather is driven by the heat and water vapor in the atmosphere. A warmer atmosphere has more energy and more water vapor, and weather in general is more intense. Storms are more powerful, winds are stronger, rainfall is more intense.

 

Some places will be much hotter. Some places may even be colder at times because stronger winds are bringing colder air from the polar regions. But when that happens, the warm air goes to the polar regions which end up much hotter. The average is still higher.

 

The big problem for humanity with climate change is not the absolute change in temperature. The big problem is that civilization relies on so much immovable infrastructure (cities, transport, water supplies etc) that has been built based on current weather patterns. If we were nomadic and could pick things up and move them when the weather becomes a problem, it would not be such an issue. We can't.

[Ian]

 

2 hours ago, onetrack said:

I have a serious level of concern whereby an international panel, formed by a defacto Govt (the U.N.) that is essentially responsible to no-one (because it's a global organisation), bases its entire existence on one factor, and one factor alone - global warming.

This panel must continue to justify its existence to its masters (the U.N. bureaucracy) by constantly keeping to an agreed story - that the world is heating up to the point whereby in the very near future, mankind will cease to exist, such will be the drastic climatic changes.

The view that climate change is wrong is slowly being crushed by real science, because the issue appears to be real. Doing a little bit of "reading" rather than opining you might find that the IPCC was created by the US Government's lobbying to counter the impact of the unrestrained views and opinions of independent scientists allowing a political component to the views.

Real science and research is slowly pushing the doubting Thomas' and vested interest groups into submission.

The IPCC has no power it is simply a platform which is actually using aggregate research to provide a consensus point of view. It's not made up of EU bureaucrats and has the support of 99% of scientists.

You make it sound like these people have nothing better to do, they do. The simple fact that your views are based on a spurious grasp of science and research is disturbing however I'll try to correct them.

 

2 hours ago, onetrack said:

The IPCC is basically examining climate records for the last 30 or 40 years, with an occasional mention of date back to the 1700's, as regards climate variations.

Climate records, justified by strong science go back millions of years. The closer you get to the present day the more accurate these records get. Nature is a Science Journal which is a good place to start https://www.nature.com/articles/nature.2016.20673

Again the IPCC provide an aggregate view of the current scientific consensus, watered down by politics.

2 hours ago, onetrack said:

Meantimes, we in the real world, know that figures and measurements are rubbery things that can be adjusted to match the storyline - particularly when the inputs to those figures and measurements are so numerous, that even with quantum computing, one would still be struggling to produce accurate climatic variation answers.

The real world is one where opinions are based on fact and extrapolated models. Yes models may be wrong but they get better over time.

2 hours ago, onetrack said:

Even now, the scientists and medical researchers have discovered that air pollution, mostly caused by industry and transportation sources, has been an important factor in the major and excessive level of COVID-19 deaths in Northern Italy.

When you make statements like this back it up with a link to a journal, Government website or other source would be helpful. But please no facebook sources 😉

Here's a good source

https://www.newscientist.com/article/2258774-air-pollution-linked-to-greater-risk-of-dying-from-covid-19-in-the-us/

Edited December 2, 2021 by Ian

[turboplanner]

20 minutes ago, Ian said:

 

The view that climate change is wrong is slowly being crushed by real science, because the issue appears to be real. Doing a little bit of "reading" rather than opining you might find that the IPCC was created by the US Government's lobbying to counter the impact of the unrestrained views and opinions of independent scientists allowing a political component to the views.

The NASA graph you posted earlier shows climate at zero/baseline as late as the mid 1970's rising 1 degree by 2020; an increase of 1 degree in 45 years.

In the 2018 Summary for Policymakers [countries, including Australia] the IPCC said "Human activities are estimated to have caused approximately 1.0 deg C of global warmimg above pre-industrial levels [1760].........global warming is likely to reach 1.5 deg C between 2020 and 2052 if is continues to increase at the current rate. [their 1 degree having been changed  from their earlier report which was similar to NASA to 1 degree in 258 years.

There's no opining here, the sources have been posted earlier.

How do you explain this discrepancy?

[aro]

The amount of fossil fuels being burned and the rate of change has increased markedly in the last 50 years. So it doesn't matter whether you pick a baseline of 50 years ago or 250 years ago, the change is very similar because most of it occurred in the last 50 years.

[Old Koreelah]

5 minutes ago, aro said:

The amount of fossil fuels being burned and the rate of change has increased markedly in the last 50 years. So it doesn't matter whether you pick a baseline of 50 years ago or 250 years ago, the change is very similar because most of it occurred in the last 50 years.

I’ve challenged some people to visualise the rivers of oil that humans are burning each day; surely we can’t keep doing that.

[facthunter]

WE are energy junkeys.  Nev

[aro]

I saw a figure recently (I haven't tried to do the calculation myself) that "20% of Australia's grazing land covered with solar would provide the whole world with carbon-free energy". Of course,

a) that's a lot of land and

b) transport and storage is still a problem

but the energy seems to be there.

 

Mike Cannon-Brookes is aiming to export renewable energy from the Northern Territory to Singapore via undersea cable - helping countries without Australia's land area to meet renewable energy obligations.

[turboplanner]

1 hour ago, aro said:

The amount of fossil fuels being burned and the rate of change has increased markedly in the last 50 years. So it doesn't matter whether you pick a baseline of 50 years ago or 250 years ago, the change is very similar because most of it occurred in the last 50 years.

But when you are telling the world civilisation as we know it is about to end you use the same baseline and you show the progression year by year.

 

However, when you set the baseline, report the alarming increase on that baseline, and then just five years later push the baseline backwards by 215 years you are changing the gradient, doctoring the figures; your believability goes out the window.

[spacesailor]

I always thought the bronze-age was the Worse carbon release in any history.

They had to burn many trees to meke bronze from raw copper !.

Burn the tree to make charcoal, burn that charcoal to make the fire hot enough to make Bronze, for !

WAR.

Then came Nuclear bomb testing, that burt untold cubic miles of OXYGEN. 

spacesailor

[APenNameAndThatA]

On 30/11/2021 at 7:15 AM, Thruster88 said:

Growing food versus fuel is always going to be controversial. On a typical Australian broadacre crop farm the farms diesel requirement could be produced off 4% of the farms area. 1 ton of canola = 400l bio diesel.

 

It is often said that bio diesel and grain ethanol produce more carbon pollution from the inputs than is saved from the renewable products produced, obviously from economics that is simply not the case.

 

At the moment world grain supply and demand is very well balanced as indicated by reasonably high grain prices. Any major increase in bio fuels will result in higher food prices. There is limited ability to increase production as I see it.

That seems too good to be true, but I'm not suggesting that you don't know a *lot* more about it than I do. 

[APenNameAndThatA]

8 hours ago, turboplanner said:

But when you are telling the world civilisation as we know it is about to end you use the same baseline and you show the progression year by year.

 

However, when you set the baseline, report the alarming increase on that baseline, and then just five years later push the baseline backwards by 215 years you are changing the gradient, doctoring the figures; your believability goes out the window.

No one said civilisation was about to end (straw man). In your mind's eye, the gradient might change, but the figures have been there for a long time if you want to look them up.

 

50% of the earth's atmosphere is below 18 000 ft. Thats about 6 km up. 6 km is not very far. I can walk that far. The earth has very little atmosphere. Meanwhile, every day, people use 15 000 000 000 L of oil (? about half of which is burnt) I don't know how come climate change is so slow. (Source for the oil use is Worldometer and a barrel of oil being 158 L and rounding down.) If you burn five or 10 billion litres of oil a day, that's going to do something, IMHO. 

 

[onetrack]

Ian, here's the link to the scientific report that came to the conclusion that air pollution in Northern Italy (specifically the Po Valley, which is highly industrialised) led to a far greater mortality rate for COVID-19 patients, than many other regions in Italy.

 

https://www.sciencedirect.com/science/article/pii/S0013935120313566

[turboplanner]

5 hours ago, APenNameAndThatA said:

No one said civilisation was about to end (straw man).

No they didn't, but you misquoted me. I said "civilisation as we know it."

[turboplanner]

Future Fuels – Hydrogen

CO2 is not measured on Australian vehicles because exhaust emission of CO2 is dependent on the standard of the fuel and diesel is under threat because it is part refined and relatively dirty.

 

However, CO2 and Global warming are not the only reason we should be looking for alternative fuel. Since 1979 fuel costs have risen way beyond the CPI to the point where long distance travel for holidays is less affordable than it was in the 70s. This in turn has lowered the income of many country towns which in the 70s had thriving tourism facilities.

 

So cost reduction is right up near the top of the list of reasons for finding a different fuel.

Some fuels which may produce less CO2 will be knocked out by this factor.

 

Car Manufacturers have handled the cost increase by selling excitement and allowing more applications in SUV and these are now market leaders, while non-towing cars have become lighter, retained low initial costs and are starting to achieve highway fuel consumption of around 4 litres/100 km.

 

The truck industry has been able to take another path by increasing the volume of freight carried be changing maximum length and height dimensions and reducing fuel consumption.

A B Double today with one driver and one Prime Mover carries as much volume as three semi trailers of the 1970s, and this has allowed companies to survive in applications where Prime Movers consume massive amounts of fuel per year.

 

When we look at future fuels we have to match them to the applications people want to operate in.

 

Hence, EV so far is not much use to the No1 sector of the car market because of towing power demand and long distances at high speed, and with trucks required to keep within maximum dimension and weight limits, so aside from the proposed fuel working or not working in an engine there are the practical limits which must be met for long term success.

 

The attached story from the Age yesterday is about the first Hydrogen Supply Station in Australia which is being built at Truganina in Melbourne. This is for Hydrogen Gas to be burnt by an ICE engine (as against a hydrogen fuel cell vehicle with electric wheel motors). Some people have said Hydrogen will make EVs obsolete.

 

Truganina is an industrial zone west of Melbourne and an ideal B Double departure point for Sydney, Brisbane, Adelaide, Darwin and Perth.

 

My job is to design trucks which can be ordered, delivered within about six weeks and go straight into service for their lifetime which is about 3 million km, so I was casually looking at what would be required for a hydrogen truck (leaving the engine to be designed and built by engine manufacturers).

 

The current extremes with diesel fuel for a Prime Mover are customers who believe their business is carrying freight, not fuel so buy their fuel enroute and set a maximum fuel tank capacity at 800 litres. Offsetting them are customers who believe they get ripped off by service stations so do a bulk deal with an oil company and carry enough fuel for the trip. They require a minimum 2500 litres. If you thought W&B was hard with an aircraft try getting these extremes within the wheelbase and meeting maximum axle loadings. The 2500 litres required square aluminium tanks which produce maximum volume per metre of length, jamming the front tank within about 50 mm of the steer tyre and the rear tank about the same to the drive tyre, the outer face at the legal truck width limit and the inner face allowing a tiny space for the prop shaft.

 

So can hydrogen fit into this? Well we don’t know, because the fuel vessel has to be decided. LNG trucks required a heavy steel tank with fuel at 2000 psi; will hydrogen require a similar heavy tank. What will be the fuel consumption of hydrogen compared to diesel? Well we don’t know that yet.

 

What we do know is that with only one refuelling point, the first trucks at least will have to carry enough hydrogen to make the round trip Melbourne-Brisbane-Melbourne etc, or limit their operations until other supply stations can be built, and these look like very expensive stations, not just stations with holding tanks like petrol and diesel with a tanker delivering the product.

 

Unless the engine burns a lot less hydrogen than diesel on the same task or unless we can carry the fuel at low pressure within about a t6 mm skin, then we are not going to be able to enter the market with these trucks until there are hydrogen supply stations within our range, because we have no legal space.

 

Before the customer makes a hydrogen commitment, he’s going to be looking at the cost of hydrogen and the consumption per kilometre. Take a look at the attached graph and you can see why – his fuel bill for diesel exceeds the cost of the Prime Mover in about 12 months, and he’s paying more than a million dollars every four years!

 

If we look at hydrogen for aircraft, the size and weight of the fuel tank will also be a critical factor in deciding whether to switch.

WS00163.pdf

[Ian]

While Hydrogen may play a part in low emission steel production, it's hard to see it being used as a transport fuel. As a storage medium its less efficient than using compressed air.

Storage is hard, to get around this you have some people promoting ammonia as the solution however handling ammonia is difficult and it has a low energy density.

There are also people promoting hydrogen saying that we can just substitute hydrogen for natural gas. However this is harder said than done, from the following link

 

Quote

Unfortunately, because the physical and chemical properties of hydrogen differ significantly from those of natural gas, it is not possible to simply exchange natural gas for hydrogen in the existing natural gas system. One limiting factor is the durability of existing pipelines. Some metal pipes can degrade when they are exposed to hydrogen over long periods, particularly with hydrogen in high concentrations and at high pressures. The effect is highly dependent on the type of steel and must be assessed on a case-by-case basis. Making the necessary modifications to strengthen pipelines would be costly, but they pale in comparison to constructing an entirely new network. 

Energy during peak generation periods is likely to get very cheap as solar generation outstrips demand. However energy intensive plant for manufacturing things like fuel tend to need to run 24x7 to make a commercial return. I suspect that the people who are promoting this either have vested interests like Twiggy (who wants the government to fund his steel operations) or can't do maths.

 

My view is that even if you don't agree with climate change the rest of the world does and you're going to lose access to your cheap dinosaur fuel.

What are you going to run on in the future? I don't think it will be hydrogen so what else out there can you buy that's economical.

On that note I might fire up my still and light my pipe and start bootlegging to all you pilot types. Maybe it will fund my next plane...

 

 

 

[onetrack]

Both the U.S. and Japan have very active and large Energy Efficiency Depts working flat out on getting hydrogen storage systems to be effective, acceptable cost, and compatible with fossil fuels.

 

Both countries have targets within the next few years that they seriously intend to meet. The real bugbear with hydrogen is trying to densify the gas to meet the same energy density levels as fossil fuels, without incurring major weight gain or high costs.

Cryogenic hydrogen is the way to densify hydrogen, but I cannot see any satisfactory solution, as regards making a small and low cost cryogenic unit that can be fitted to vehicles - so gas compression appears to be the way to go. A carbon fibre matrix appears to be the direction the tank design is heading.

 

https://www.energy.gov/eere/fuelcells/hydrogen-storage

 

 

[onetrack]

Below is a link to the Japanese Govts roadmap summary, as regards their aim to build a hydrogen economy. Be assured the Japanese effort to build a hydrogen economy is not a fractured effort - it is fully co-ordinated at the highest Govt level, and funded with multiple billions of yen, to ensure that their roadmap targets are largely met.

The Japanese are targeting 2025 as the date for a major increase in hydrogen use, and 2030 as the date for establishing international hydrogen supply chains.

However, the Japanese appear to be concentrating on hydrogen fuel cell technology as the primary method of hydrogen use, rather than directly using hydrogen in IC engines, which appears to be more of a trend in the U.K. and the U.S.

 

https://www.meti.go.jp/english/press/2017/pdf/1226_003a.pdf

[turboplanner]

24 minutes ago, onetrack said:

However, the Japanese appear to be concentrating on hydrogen fuel cell technology as the primary method of hydrogen use,

Probably because they've had fuel cell production cars, buses and trucks since around 2005, and the only issue seems to be cost, at present about 3 times a petrol powered identical car, so a killer until some breakthroughs.

 

 

[spacesailor]

Almost on par with those electric Tesla cars, !.

Very expensive in comparison to the standard Toyota.

Car that is.

spacesailor

[Clark01]

For a bunch of technology-types, there's some pretty, err, fascinating reading here!

 

I'll try to put the climate-science debate aside. But to say- in what other area of science, when 98% of the science experts in the field say something is happening, do we say (with imagined authority!) "Oh they must be wrong". Have a look at the climate skeptics regularly referenced in the Murdoch Press. Its the same 2-3 people all the time. And none of them are climate scientists- mostly they're geologists.

This little YouTube video explains the issue well.

 

Climate change is real, and we have to do something about it. That's hard. 

 

And fossil fuels are very energy dense. Which is hard to replace. 

 

There's nothing new about hydrogen. We're in at least the third hydrogen hype cycle I've seen. Have a read of the book "They Hype About Hydrogen", written in 2004.  There's even been hydrogen aircraft- see the TU155 for example.

 

Today, governments around the world (including Australia) are funding lots of work targeting "green" hydrogen at $2/kg. They hope we'll get there by 2030. Changing units around, that works out at ~$16/GJ. The last 12 months, natural gas has been around $5-$8/GJ.  Hmm. Tough market for hydrogen at $2/kg! 

 

And the $2 price doesn't include storage or transport costs associated with hydrogen. It is far less energy dense than natural gas- so you need around 3-4x the storage. And it makes a lot of pipe materials brittle. Not to mention it burns colourlessly, is hideously explosive, etc, so HSE costs are far greater.

 

All in all, for hydrogen to compete against natural gas, something will need to change the economics dramatically, even at our hoped-for goal of $2. That something is either legislation, or a carbon price. Good luck with that!

 

Additional thoughts:

• I've plenty of experience trying to burn hydrogen in a reciprocating engine. It works. Kind of. They did it in WWII. JCB are doing it now in tractors. There's been lots of research in Australia on it. But the engines don't last very long. Due to how easy it is to get the hydrogen to burn, its very difficult to precisely control ignition timing. So you end up with a lot of knock, and the engine wears out. There's also issues with lubrication, etc.
• Fuel cell vehicles need a large battery, as fuel cells can't ramp up/down in power output very quickly- so you need a battery as a buffer. So in practice, a fuel-cell EV is actually an electric vehicle, plus a hydrogen tank and fuel cell. I'm  not a smart man, but that makes the economics of FCEV vs EV pretty clear..
• For passenger cars, this talk of EV and range issues is nonsense in 2021. There are plenty of EVs that have >500km range. Some you can buy today in Australia. The latest Hyundai EV, the Ioniq 5, has a range of 480km, and can recharge from 10-80% in 18 minutes. Show me a petrol car journey where someone drives 480km and doesn't stop for at least 18 minutes...
• Sure, to get that sort of recharge rate you need the latest EVs and the latest standard chargers. And there's not many of these in Australia. But the technology can do it, and it exists at scale already. Just not here. Sigh.
• Sure, the Ioniq 5 is not a cheap car, at around $72k in Australia. But you can buy an MG ZS today in Australia for $40k, with close to 300km of range. The direction of this industry is clear.
• The talk that EVs can't tow is, again, old fashioned nonsense. The Rivian R1T (announced for Australia, available in the US) and Hummer (about to be released in US) have towing capacities in excess of 3500kg. Their range unladen is 500km. Someone has already towed a large car across the US using a Rivian. Yes, it was a bit of a PITA, but it is doable.
• Average car changeover time in Australia is 8 years, which makes things slower here..
• Electric short-journey buses are happening in large numbers in the US and China. The economics work for shorthaul.

EVs work, and will be everywhere in passenger cars, even in our neolithic Australia, over coming years.

I won't hold my breath for a hydrogen-powered truck. Or plane (beyond some research project).

There's plenty of examples of electric short-trip aircraft. They make sense for training and what I think of as the "jet ski" model- go for a short buzz for sh*ts and giggles. Very low cost to operate. Bugger all noise.

Fossil fuels are energy dense, and hard to replace. But we can address a lot of our climate challenges doing the easy stuff- convert the short-haul and passenger car fleets. That leaves lots of fossil fuel in the ground for long-haul transport. And we deal with those CO2 emissions some other way.

 

-C

 

 

 

 

[Clark01]

Ooh. And don't even start me on "baseload". Its such nonsense. A term power system engineers used, that was misused for political purposes.

 

We DO NOT need more "baseload". The Australian Energy Market Operator, the people who run our energy system, make this very clear in documents like this one - what we need is more flexible generation, that can follow changes in net demand. Yes, in an old world we needed baseload. But that world doesn't exist today due to massive changes in our demand (think- things like air conditioners which double demand just a few days of the year) and supply (intermittent solar and wind).

 

There was a period last weekend where South Australia had 135% of its demand met by wind and solar alone. The excess energy was mostly exported to Victoria. Over a 48 hour period wind and solar met 108% of demand, and over a 93 hour period they met 100% of demand.

 

Sure, there's very major challenges to operating a power system with so much wind and solar, and SA relies on interconnection to other states to keep things reliable. But don't mistake "its hard" to "its impossible". 

 

 

Edited December 3, 2021 by Clark01

[turboplanner]

3 hours ago, Clark01 said:

Ooh. And don't even start me on "baseload". Its such nonsense. A term power system engineers used, that was misused for political purposes.

 

We DO NOT need more "baseload". The Australian Energy Market Operator, the people who run our energy system, make this very clear in documents like this one - what we need is more flexible generation, that can follow changes in net demand. Yes, in an old world we needed baseload. But that world doesn't exist today due to massive changes in our demand (think- things like air conditioners which double demand just a few days of the year) and supply (intermittent solar and wind).

 

There was a period last weekend where South Australia had 135% of its demand met by wind and solar alone. The excess energy was mostly exported to Victoria. Over a 48 hour period wind and solar met 108% of demand, and over a 93 hour period they met 100% of demand.

 

Sure, there's very major challenges to operating a power system with so much wind and solar, and SA relies on interconnection to other states to keep things reliable. But don't mistake "its hard" to "its impossible". 

 

 

Baseload is the power required to be generated in order to keep boilers from cracking. Boilers must be kept warm at all times. In the past, the power companies would sell us power cheaper if we bought it at night when they were on baseload. The renewables started advertising their ability to meet "baseload" as a gimmick, and many people fell for the ruse and thought they could produce all the power we needed.

 

However twice in the last couple of years I've watched  the dashboard as the load came on at night, once to the extent that supply to 100,000 homes in Melbourne had to be shut down those conditions require Peak Power, and power stations up the east coast fire up to maximum capacity. On both occasions at Peak Power the Renewables contribution was 1%. Renewables are like a car without an accelerator, and at this stage there's no way out. If you invest in enough renewables to make Peak Power, and there's nothing in the way of doing that, the Capital expenditure kills you on the days, the bulk of the year, when you only need to generate a fraction of Peak Power. The power grid at present is an open market, so on a cold day the coal-fired boilers have to keep going at base load, but renewables can switch down amd sell power much cheaper. This is forcing investors out of coal-fired and we are facing some issues on hot days over the next few years.

 

[Flightrite]

With the amount of ugly ghettos being built these days to house the masses they better come up with something better than Dino power😂

[turboplanner]

3 hours ago, Clark01 said:

• For passenger cars, this talk of EV and range issues is nonsense in 2021. There are plenty of EVs that have >500km range. 

Our governments are going to have to step in on range quoting. Australia's task is not 500 km at 80 km/hr, but around 800 km at 100 km/hr with a short motel stay in between legs. Airpower demand is exponentially higher with speed above 80 km/hr. That's not the requirement for all Applications, but it is a sizeable requirement for Australian operations.

 

3 hours ago, Clark01 said:

• Sure, the Ioniq 5 is not a cheap car, at around $72k in Australia. But you can buy an MG ZS today in Australia for $40k, with close to 300km of range.

The market share for Australia is very telling, and the biggest issue is pretty much the same as the reason buyers wiped out Australian built cars. If they can only just stretch to a $26,000.00 new car there's no use offering them a $40,000. The same issue goes up the price range - OK for rich people, not for families. The new car sales per month by model tells the story, and this same discussion has now been going on for years.

3 hours ago, Clark01 said:

• The talk that EVs can't tow is, again, old fashioned nonsense. The Rivian R1T (announced for Australia, available in the US) and Hummer (about to be released in US) have towing capacities in excess of 3500kg. Their range unladen is 500km.

Leaving aside price, Australia has two key requirements for this market:

(a) a highway speed of 100 km/hr (which is dicussed above) and

(b) 3000 kg trailer towing capacity, already compromised because although vehicles are rated to pull a trailer, most can only meet that     GCM by operating with the driver only and no load in the ute tray. 

So we have two issues working against EV

(a) The exponential power demand of Airpower discussed above

(b) increased rolling resistance from a loaded trailer demanding more power.

 

These things are not insurmountable, but its wrong to suggest you can race into that market with undeveloped product designed for another country.

 

 

 

[Clark01]

58 minutes ago, turboplanner said:

Baseload is the power required to be generated in order to keep boilers from cracking. Boilers must be kept warm at all times. In the past, the power companies would sell us power cheaper if we bought it at night when they were on baseload.

 

Indeed. Fully agree with this definition of "baseload". The difference is that in much of the political, and somewhat media, debate, the statement is we need more baseload. And the reality is the opposite. The last thing we need is a generator than can't ramp down below a certain point. This is one of the key challenges to the coal fleet- they can't ramp any lower, and, as you say, market prices end up negative- the coal generators have to pay to remain connected. That's not a long-term sustainable solution.

 

58 minutes ago, turboplanner said:

However twice in the last couple of years I've watched  the dashboard as the load came on at night, once to the extent that supply to 100,000 homes in Melbourne had to be shut down those conditions require Peak Power, and power stations up the east coast fire up to maximum capacity. On both occasions at Peak Power the Renewables contribution was 1%

Its hard to respond to this without seeing data. But the AEMO dashboard publishes the energy mix in real time. Right now coal is meeting 49% of total demand across the east coast. And I can't recall seeing a time where renewables has been 1% of national electricity market (NEM) demand for...years.

 

I'm being deliberate in referring to the "NEM".. That's the whole idea of an electricity "grid"- it provides geographical diversity, so that the places its not sunny, you can import solar from where it is sunny. Before solar and wind, we did the same with coal, gas and hydro- importing hydro from the snowy into QLD at times of peak demand (a hot afternoon in Brisbane). Cherry picking a particular city or geography and saying "this area isn't operating on renewables because it isn't sunny or windy right now, and so renewables can't work" is just that- cherry picking. It misses the entire complex mesh that is a modern electricity system.

 

58 minutes ago, turboplanner said:

If you invest in enough renewables to make Peak Power, and there's nothing in the way of doing that, the Capital expenditure kills you on the days, the bulk of the year, when you only need to generate a fraction of Peak Power.

 

This is the pessimistic way of representing the situation. An alternative portrayal would be to say that "If you build enough renewables to meet our maximum demand, then there will be many periods where we have excess, and thus very low price (free, possibly even negative price) energy". That "free" energy can be used for all sorts of thing- making hydrogen, desalinating water, soaking up CO2, making synthetic fuels, etc. 

 

The reality is there's a hell of a lot of renewables still to be built, (AEMO provide very clear forecasts). As we do that, we will have periods, like SA last weekend, where there are areas with excess generation capacity. Historically people curtailed (turned off) generators during these times. But even then, the plant keeps getting built, so the economics work. And today, plenty of industries are realising that if they can be flexible in their demand, we can soak up the excess supply to make the sorts of things I reference above.

 

A domestic version of this we see in household pricing- you refer to off-peak hot water control, which was designed to soak up excess capacity in the middle of the night (to keep boilers warm). Today we see the same thing happening in the middle of the day- there are tariffs that have lower prices in the middle of the day, to encourage people to turn things on when we have excess solar.

 

 

58 minutes ago, turboplanner said:

This is forcing investors out of coal-fired and we are facing some issues on hot days over the next few years.

 

This has been a long-held fear, but its just not true today. Literally today, AEMO have declared we'll be ok, although there's some risk of "extreme events". That's always been the case. And the risk is actually because of coal units that have been lost- Callide had a fire, Yallourn had some flooding issues, and a bunch of gas is offline. 

 

 

Edited December 3, 2021 by Clark01