Monday, March 25, 2024

Locos which keep going when the wire ends

I was doing some research on "bi-mode" or "dual-mode" locomotives, which can use both electric power from an overhead catenary, as well as diesel power.   Diesel-electric locos already use electric engines to turn the wheels: the diesel engine drives an electric generator which in turn drives the wheels.  Why this apparently inefficient arrangement?  Because an electric engine can provide full torque at zero RPM, unlike plain diesel engines, allowing for faster acceleration from stops.  

Locos which can use both diesel and electricity as energy sources are called electro-diesel locos, whereas, locos using a diesel motor to drive an electric generator are called diesel-electric.  Some diesel-electric locos also have a battery to allow for a larger power draw during acceleration.  

Obviously, if the loco is on a stretch of track where there is electric power, then it would make sense to use the electricity available to run the loco's electric engine.  That is exactly what Siemens Vectron Dual-Mode locomotives does.




From Siemens website:

 

Vectron Dual Mode – keeps going where the wire ends

The Vectron Dual Mode is the up-to-date answer to changing route requirements. The dual power locomotives unite the advantages of full-featured diesel locomotives with those of electric locomotives. This combination empowers you to respond flexibly at all times to your traction requirements – so you'll always keep moving, with or without an overhead wire.

Whenever an overhead wire is available, it should be used. Electrical operation is much more cost-effective and environmentally friendly than diesel operation. But because Germany [and the UK, Australia, the USA .....] will continue to have many non-electrified sections of track for a long time to come, many diesel locomotives still run under an overhead wire – without actually using it. This makes very little economic or ecological sense. The Vectron Dual Mode excels in both operating modes, offering a real alternative to diesel-only operation.

Whether you want to react flexibly to unplanned diversions or boost environmental performance in conurbations: the Vectron Dual Mode offers you a wealth of advantages in your day-to-day operations.

With the Vectron Dual Mode, you'll handle a wide range of traction tasks much more economically than with a standard diesel locomotive. Every kilometre saves fuel, and thereby reduces energy costs. You'll also reduce the number of hours your diesel alternator set is operating. Altogether, you'll benefit from a reduction in energy and maintenance costs of up to 53%.  [The savings obviously depend on what percentage of the total network is electrified.  On the other hand, diesel locos have to keep running even when they are stationary.  Given that hybrid cars use up to 40% less fuel than petrol cars because the engines don't run when the car is stationary, and also because they recharge their battery as they slow down or go down a hill, significant energy savings appear quite possible, provided the loco also has a battery.]

The issue of environmental pollution is becoming increasingly important in cities and metropolitan areas. With the Vectron Dual Mode, you'll make an important contribution to sustainable freight transport. By taking advantage of electricity wherever possible, you reduce carbon dioxide, nitrogen oxides and particulate matter emissions. This lets you reduce your annual local emissions by 950t of CO2, 6t of nitrogen oxides and 37kg of particulate matter compared with a standard diesel locomotive – and significantly improve your fleet's environmental performance.  [Again, the percentage of electrified track will alter these numbers.  For example, only 10% of Australia's railway track is electrified.  However, a much larger percentage of track in urban areas and conurbations is electrified, and a larger percentage of total traffic takes place on these networks.  For example, in Victoria, V-Line trains which serve regional and country destinations travel for part of their journey on electrified tracks.  On my journeys from a provincial town 200 kms from the city into the big smoke, half the distance is electrified.]


There is another advantage.  To extend existing electrified sections, installing overhead electric wires has to be done from the edge of the existing electrification to the next station or to a depot, which makes for substantial lump-sum outlays.  In other words, it has to be done in expensive chunks.  With a bi-mode loco, electrification can proceed at, say, 5 kilometres at a time, so that the electrified network can be gradually extended over time.  The loco just keeps going under diesel power when it reaches the end of the wire.  Also, the electrified sectors don't need to be contiguous, as the diesel engine could be used across the gaps.  

A good idea.


See also:

Sunday, March 24, 2024

Exxon's breathtakingly accurate climate predictions


From The Guardian


The oil giant Exxon privately “predicted global warming correctly and skilfully” only to then spend decades publicly rubbishing such science in order to protect its core business, new research has found.

A trove of internal documents and research papers has previously established that Exxon knew of the dangers of global heating from at least the 1970s, with other oil industry bodies knowing of the risk even earlier, from around the 1950s. They forcefully and successfully mobilized against the science to stymie any action to reduce fossil fuel use.

A new study, however, has made clear that Exxon’s scientists were uncannily accurate in their projections from the 1970s onwards, predicting an upward curve of global temperatures and carbon dioxide emissions that is close to matching what actually occurred as the world heated up at a pace not seen in millions of years.

Exxon scientists predicted there would be global heating of about 0.2C a decade due to the emissions of planet-heating gases from the burning of oil, coal and other fossil fuels. The new analysis, published in Science, finds that Exxon’s science was highly adept and the “projections were also consistent with, and at least as skillful as, those of independent academic and government models”.

Geoffrey Supran, whose previous research of historical industry documents helped shed light on what Exxon and other oil firms knew, said it was “breathtaking” to see Exxon’s projections line up so closely with what subsequently happened.

“This really does sum up what Exxon knew, years before many of us were born,” said Supran, who led the analysis conducted by researchers from Harvard University and the Potsdam Institute for Climate Impact Research. “We now have the smoking gun showing that they accurately predicted warming years before they started attacking the science. These graphs confirm the complicity of what Exxon knew and how they misled.”

The research analyzed more than 100 internal documents and peer-reviewed scientific publications either produced in-house by Exxon scientists and managers, or co-authored by Exxon scientists in independent publications between 1977 and 2014.

The analysis found that Exxon correctly rejected the idea the world was headed for an imminent ice age, which was a possibility mooted in the 1970s, instead predicting that the planet was facing a “carbon dioxide induced ‘super-interglacial’”. Company scientists also found that global heating was human-influenced and would be detected around the year 2000, and they predicted the “carbon budget” for holding the warming below 2C above pre-industrial times.

Armed with this knowledge, Exxon embarked upon a lengthy campaign to downplay or discredit what its own scientists had confirmed. As recently as 2013, Rex Tillerson, then chief executive of the oil company, said that the climate models were “not competent” and that “there are uncertainties” over the impact of burning fossil fuels.

“What they did was essentially remain silent while doing this work and only when it became strategically necessary to manage the existential threat to their business did they stand up and speak out against the science,” said Supran.

“They could have endorsed their science rather than deny it. It would have been a much harder case to deny it if the king of big oil was actually backing the science rather than attacking it.”

Climate scientists said the new study highlighted an important chapter in the struggle to address the climate crisis. “It is very unfortunate that the company not only did not heed the implied risks from this information, but rather chose to endorse non-scientific ideas instead to delay action, likely in an effort to make more money,” said Natalie Mahowald, a climate scientist at Cornell University.

Mahowald said the delays in action aided by Exxon had “profound implications” because earlier investments in wind and solar could have averted current and future climate disasters. “If we include impacts from air pollution and climate change, their actions likely impacted thousands to millions of people adversely,” she added.

Drew Shindell, a climate scientist at Duke University, said the new study was a “detailed, robust analysis” and that Exxon’s misleading public comments about the climate crisis were “especially brazen” given their scientists’ involvement in work with outside researchers in assessing global heating. Shindell said it was hard to conclude that Exxon’s scientists were any better at this than outside scientists, however.

The new work provided “further amplification” of Exxon’s misinformation, said Robert Brulle, an environment policy expert at Brown University who has researched climate disinformation spread by the fossil fuel industry.

“I’m sure that the ongoing efforts to hold Exxon accountable will take note of this study,” Brulle said, a reference to the various lawsuits aimed at getting oil companies to pay for climate damages.



 


Saturday, March 23, 2024

GWR's New Battery Powered Train

Step by step we move away from fossil fuels in railways. 

 Electrification is overall cheaper on busy lines. To date, diesel has been cheaper on less-used lines, because the higher capital cost of installing third-rail/overhead-wire technology isn't offset by the cheaper running coats of electricity.    

I've talked before about battery-powered electric trains which charge from the overhead catenary when they travel on track with electrification, allowing them to travel some way on un-electrified track. 

 Which of these alternative approaches would be better would depend on distances travelled and how fast overhead catenary-charged batteries can charge.  In Australia, for example, rural towns are much further apart than the towns served by this line in England, which are roughly 5 miles apart.   This would require more batteries, on the train and next to the track, and more charging time.  

An alternative is a locomotive which can run on either diesel or electric power, called "electro-diesel" or "bi-mode"  locos (not to be confused with diesel-electric motors), such as the new trains in NSW (which I know I wrote about here on Volewica, but have been unable to find the article)



Air, ocean and ice climate records tumbled in 2023

From Weatherzone

The World Meteorological Organization has confirmed that 2023 was an astonishing year for our planet’s climate, with records obliterated in the atmosphere, hydrosphere and cryosphere.
 

Atmosphere


Global air temperatures frequently made headlines around the world in 2023 as records fell month after month.

Every calendar month from June to December set a new global average near-surface air temperature record for that time of year.

This string of exceptional warmth in the second half of 2023 pushed the annual global mean air temperature to 1.45°C (±?0.12?°C) above the 1850 to 1900 pre-industrial baseline. According to the WMO, this was the highest annual mean temperature on record, beating the previous record from 2016 by 0.16ºC.

Oceans


The record warmth in Earth’s atmosphere last year was also mirrored in the oceans, with global sea surface temperatures reaching record-breaking levels from March onwards.

Every month from April to December set a new respective monthly record in 2023, while a new daily sea surface temperature record was observed in August (note that this has since been exceeded in 2024).


 
Image: Daily global sea surface temperatures between 1979 and 2024 to date, based on the ERA5 dataset. Source: Copernicus Climate Change Service


The global mean sea level also reached a new record height in 2023, driven by abnormal ocean warmth and increased melting of glaciers and ice sheets.

According to the WMO, “the rate of global mean sea level rise in the past ten years (2014–2023) is more than twice the rate of sea level rise in the first decade of the satellite record (1993–2002).”

Ice


Parts of the cryosphere – the frozen portions of our planet – also broke records in 2023.

Antarctic sea-ice extent reached record lows for the seasonal minimum extent in February and maximum extent in September.




Glacier melt was also pushed to new levels in 2023. According to the WMO, “preliminary data from the global set of reference glaciers for the hydrological year 2022-2023 show they experienced the largest loss of ice on record.”

What made 2023 so warm?


Climate change and El Niño were both contributing factors to the record-breaking warmth in 2023. However, these drivers alone aren’t enough to account for the magnitude of last year’s abnormal warmth.

According to the Copernicus Climate Change Service, other influences that may have contributed to the exceptional state of the climate in 2023 are:
  • Enhanced stratospheric water vapour due to the eruption in January 2022 of the Hunga Tonga–Hunga Ha'apai volcano
  • Reduced aerosols due to lower sulphur dioxide emissions by shipping
  • The approach of the current solar cycle to its peak.

These influences are still an active topic of research and may continue to influence Earth’s global climate system in 2024. Monitoring Earth’s global climate system is an essential part of understanding how the climate is changing and what steps need to be taken, now and in the future, to mitigate its effects.

China's industrial production is picking up

 At least, if you trust the official data.   I know GDP data are massaged.  Is China now starting to "improve" other time series too?  I don't know.  For what it's worth, here's what IP looks like.  There are other indicators which are starting to hint at a Chinese economic recovery, such as the iron ore price and the Chinese steel price and paper pulp price, as well as a recovery in the stock market.  But other indicators, such as retail sales and car sales, are weak.

My estimate is that China makes up something like 15% of the world economy, but it's hard to be sure, because official GDP data are clearly materially overstated.



Monday, March 18, 2024

Why is the sea so hot?

Photgraph by Marli Miller/UCG/Getty/The New Yorker




From The New Yorker

In early 2023, climate scientists—and anyone else paying attention to the data—started to notice something strange. At the beginning of March, sea-surface temperatures began to rise. By April, they’d set a new record: the average temperature at the surface of the world’s oceans, excluding those at the poles, was just a shade under seventy degrees. Typically, the highest sea-surface temperatures of the year are observed in March, toward the end of the Southern Hemisphere’s summer. Last year, temperatures remained abnormally high through the Southern Hemisphere’s autumn and beyond, breaking the monthly records for May, June, July, and other months. The North Atlantic was particularly bathtub-like; in the words of Copernicus, an arm of the European Union’s space service, temperatures in the basin were “off the charts.”

Since the start of 2024, sea-surface temperatures have continued to climb; in February, they set yet another record. In a warming world, ocean temperatures are expected to rise and keep on rising. But, for the last twelve months, the seas have been so feverish that scientists are starting to worry about not just the physical impacts of all that heat but the theoretical implications. Can the past year be explained by what’s already known about climate change, or are there forces at work that haven’t been accounted for? And, if it’s the latter, does this mean that projections of warming, already decidedly grim, are underestimating the dangers?

“We don’t really know what’s going on,” Gavin Schmidt, the director of nasa’s Goddard Institute for Space Studies, told me. “And we haven’t really known what’s going on since about March of last year.” He called the situation “disquieting.”

Last winter, before ocean temperatures began their record run, the world was in the cool—or La Niña—phase of a climate pattern that goes by the acronym enso. By summer, an El Niño—or warm phase—had begun. Since ocean temperatures started to climb before the start of El Niño, the shift, by itself, seems insufficient to account for what’s going on. Meanwhile, the margin by which records are being shattered exceeds what’s usually seen during El Niños.

“It’s not like we’re breaking records by a little bit now and then,” Brian McNoldy, a hurricane researcher at the University of Miami, said. “It’s like the whole climate just fast-forwarded by fifty or a hundred years. That’s how strange this looks.” It’s estimated that in 2023 the heat content in the upper two thousand metres of the oceans increased by at least nine zettajoules. For comparison’s sake, the world’s annual energy consumption amounts to about 0.6 zettajoules.

A variety of circumstances and events have been cited as possible contributors to the past year’s anomalous warmth. One is the January, 2022, eruption of an underwater volcano in the South Pacific called Hunga Tonga–Hunga Ha‘apai. Usually, volcanoes emit sulfur dioxide, which produces a temporary cooling effect, and water vapor, which does the opposite. Hunga Tonga–Hunga Ha‘apai produced relatively little sulfur dioxide but a fantastic amount of water vapor, and its warming effects, it’s believed, are still being felt.

Another factor is the current solar cycle, known as Solar Cycle 25. Solar activity is ramping up—it’s expected to peak this year or next—and this, too, may be producing an extra bit of warming.

Yet another is a change in the composition of shipping fuel. Regulations that went into effect in 2020 reduced the amount of sulfur in the fuel used by supertankers. This reduction, in turn, has led to a decline in a type of air pollution that, through direct and indirect effects, reflects sunlight back to space. It’s thought that this change has led to an increase in the amount of energy being absorbed by the seas, though quantifying the effect is difficult.

Can all of these factors together account for what’s going on? Climate scientists say it’s possible. There’s also a lot of noise in the climate system. “This could end up just being natural variability,” Susan Wijffels, a senior scientist at the Woods Hole Oceanographic Institution, said.

But, possibly, something else is going on—something that scientists haven’t yet accounted for. This spring, enso is expected to transition into what scientists call “neutral” conditions. If precedent holds, then when this occurs ocean temperatures should start to run more in line with long-term trends.

“I think the real test will be what happens in the next twelve months,” Wijffels said. “If temperatures remain very high, then I would say more people in the community will be really alarmed and say ‘O.K., this is outside of what we can explain.’ ”

In 2023, which was by far the warmest year on record on land, as well as in the oceans, many countries experienced record-breaking heat waves or record-breaking wildfires or record-breaking rainstorms or some combination of these. (Last year, in the United States, there were twenty-eight weather-related disasters that caused more than a billion dollars’ worth of damage—another record.) If the climate projections are accurate, then the year was a preview of things to come, which is scary enough. But, if the projections are missing something, that’s potentially even more terrifying, though scientists tend to use more measured terms.

“The other thing that this could all be is, we are starting to see shifts in how the system responds,” Schmidt observed. “All of these statistics that we’re talking about, they’re taken from the prior data. But nothing in the prior data looked like 2023. Does that mean that the prior data are no longer predictive because the system has changed? I can’t rule that out, and that would obviously be very concerning.”

[Read more here]