Mvandenbergh

My reason for assuming that they would have made the same choices or in any case a broadly equivalent one is the fact that the BNetzA, the BMWE, and political stakeholders knew from the beginning of the renewable buildout that the combination of current grid connection arrangements, network tariffs, energy markets, and subsidies would lead to this situation and they went ahead anyway. [The BNetzA regulates the networks and the BMWE is the relevant ministry in the German context]

They did so for political and ideological reasons that I think are pretty clear to anyone who follows European politics.

Had those same political stakeholders had more direct executive control of a single national electricity system, they would have done the same thing and for the same reasons.

Yes, of course a vertically integrated system optimising for efficiency would never have made these choices but the same political decision makers who shut down Germany's nuclear fleet would never have permitted such an integrated system to operate in such an efficient way if it meant not building wind assets.

We can see the impact of a different political direction in the French electricity system, which despite being structurally similar to the decision making of the German system is in practice much more centrally directed and which despite absurd attempts to sabotage it from within France and within the EC continues to operate in a much more optimal way.

It doesn't do this through formal centralisation and integration but by the careful design of grid codes and subsidy regimes to avoid these absurdities.

I know how re-dispatch works.

The issue is that the physical reality of the network and the location of generators and loads is fixed at time of [re-]dispatch. Regardless of how you reconfigure the dispatch mechanism, there is energy that cannot be moved through the network from the wind in the North to the load centres in the South. The only way to avoid that physical reality is to either massively increase the N-S transmission capacity or to put generation capacity closer to load.

Once these generators have been placed where they are and pending extremely challenging network expansion being realised, it will always be the case that some party or set of parties bears the cost of the constraint.

If you moved the ownership and control of the transmission network and all generators into a single operator that was responsible for optimising its operation in near-real-time and that bore all the costs within a single accounting perimeter, it would do more or less what the the existing market based mechanism does: turn off the wind generators and instruct the thermal plants in the South to run instead.

Yes, it's true that in that case there would not be a "market price" paid to wind turbines that actually cannot run, nor would there be a higher re-dispatch price paid to the thermal generator. However the total system cost would still be the same. Even though the wind turbines would "lose" money because they can't run and the thermal plant wouldn't receive its market price for relieving the congestion.

Of course you could argue that this efficient single operator simply wouldn't have built the wind assets in the first place in a location where they often couldn't run but that assumes that the same policy makers who created the current outcome wouldn't have engineered the exact same outcome through the direct control they presumably would have had of the integrated operator. I will note that many American utilities actually are vertically integrated like this (banned in the EU under the Third Energy Package) and they build in the exact same pattern and bear the constraint costs internally.

Not all markets, and not even all European markets, assume a single trading zone (i.e. a copper plate network). Re-dispatch costs are high because policy choices have created a physical reality that drives high constraints.

That could have been prevented by simply not permitting connections in certain parts of the network. Yes, theoretically it could also have been prevented by forcing generators to directly bear re-dispatch costs which would have led developers to build a different set of generating assets. This would have been a different set of market mechanisms.

However, if generation decisions had been made centrally, they would have been made by the same system operators, regulators, and governments that mandated the construction of the current system and they would have therefore built the same system more or less. Do you really think that if e.g. Germany or the GB network had been centrally planned by their respective government mandated regulators and system operators, they wouldn't have put all those windfarms exactly where the market-led model we actually have has put them?

The Idirans were right all along.

It's fine but a proposal to do something without the political will to make any of the difficult compromises required to achieve them is meaningless.

I mean, ok, fine guys but this is just more empty gestures from a club of empty heads in the GroenLinks/PvdA clown-car.

I don't recall that they were against (in fact they were in favour) of the removal of the 30% tax rules intended to attract expats in, among other things, tech businesses. I don't recall that they've ever done or said anything to make the country a more attractive place to start or grow a business of any kind, let alone the kind of venture capital funded technology startups that would allow us to move a substantial fraction of our tech consumption to homegrown alternatives.

Maybe they're at least in favour of permitting for data centres so that we can at least host our own services... oh wait, they don't want those either.

Which of those references are obscure?

This is a terrible article, written by someone who is either dishonest or doesn't know what they're talking about and has never been to London, covering a paper that appears to be reasonably well done but has some serious limitations.

The study is here: https://ijbnpa.biomedcentral.com/articles/10.1186/s12966-024...

The data was collected during the 2018/2019 academic year and then during the 2019/2020 academic year (but before the Covid school closures).

First, some context: -The original ULEZ, which the referenced study looked at covers central London and should not be confused with the much larger recently expanded ULEZ which covers the whole city. Nor should it be confused with the much smaller congestion charging zone or the larger and older Low Emission Zone which covers freight vehicles. -The ULEZ rules are designed around penalising the driving of the oldest and most polluting vehicles only. In 2019 this was 80% of cars, the expanded ULEZ has overall vehicle compliance of 95%+.

As as result of the second point, it would not be expected that it would have a substantial effect on the number of vehicle journeys since 80% of passenger cars in the zone were already compliant anyway, therefore any effect at all is actually surprising. The paper notes a drop of 9% in total vehicle counts.

"Four in 10 London children stopped driving and started walking to school a year after the city's clean air zone went into effect."

This little quote heads the article. It seems like quite a result, right?

It isn't.

Let's look at the baselines here, something which immediately anyone who lives in London would be suspicious about because like me their first question would be: "who was driving their kids to school in central London in 2019? Are there enough for there to be four in ten at baseline to switch?". It turns out not many people do, and no.

Let's look at table 2 from the paper: (there were about 1000 kids in both the Luton and London samples) At baseline, 856 kids in London travelled using active modes and 105 using inactive modes In Luton that was 599 and 364 respectively

So first, we can say that "four in ten children" has to be interpreted pretty carefully here since 85% of kids were already walking to school (note that if they just took the bus the whole way this also counted as walking).

At most, we must be talking about changes to the minority of kids who weren't using active travel before, in other words maybe it's that "Four in 10 London children (of the minority who were being driven) started walking to school.

But, if we look at the changes, that doesn't quite stack up either.

In London: 47 kids switched from active to inactive (all measured based on travel "today" and in many cases there will be variation in modes across days) 44 switched from inactive to active 61 inactive/inactive 809 active/active

In Luton:

124 active/inactive 74 inactive/active 290 inactive/inactive 475 active/active

It doesn't look like, ignoring the Luton control for the moment, there was any modal shift at all for London!

Luton has proportionally shifted away from active transport and only in relative terms to the control has there been a modal shift.

This is already a much less positive message. "Kids in general less likely to walk to school, except in London where (potentially due to a low emissions zone) their behaviour didn't change." Where's my four in 10 gone?

The "four in 10" comes from the 44 kids who were inactive in the first sample but active in the second (out of 105 total inactive in first sample). Of course that is a much larger % of children from that group who switched in that direction than the 47 who switched the other way from much larger number of first sample actives. If your transition probabilities from A to B are much higher than B to A, but B is much larger group, you can end up in this situation here where you have impressive sounding % changes which nonetheless mean nothing and don't change the population behaviour at all.

It's a very fine thing, no doubt, to run multilevel binomial logistic regression models on data and come up with statistically significant odds ratios but I don't think these results remotely justify the news article headline and subhead.

>And while they are shutting down coal, they still have a huge former coal plant that is now burning biomass in London. That's a single plant that powers most of London.

Do you mean Drax? That's nowhere near London.

>And those subsidies exist because of fossil fuel industry lobbying and very willing politicians

Why would the fossil fuel industry lobby in favour of wood-chip biomass?

Which damage?

The electricity system has done most of its decarbonising under either the coalition or Conservative governments, they used quite a lot of the machinery (the CfDs, capacity market, etc) setup at the end of the last Labour government but it has been the subsequent governments that have chose the annual budgets for the auctions as well as setting up the carbon budget system.

There have been only two things that I would regard as material mistakes in this time:

First, not adjusting the max strike price for offshore wind in AR5.

Second, changing the planning rules to make it very hard to build onshore wind.

Everything else, including things like the offshore bootstraps / HND which are now receiving FID (like EGL2 which was just approved), the upcoming decision on zonal pricing, and most of all the massive buildout of solar and offshore wind generation and battery storage has happened under previous governments.

It's arguably the only area of policy which has gone quite well over the last decade, so I'm intrigued which damage you have in mind.

The timelines for encyclopaedia article contributions, editing and publishing are such that I highly doubt that an encyclopaedia bought in 2024 has much if any LLM generated content.

I wouldn't want to make that bet for an encyclopaedia published in 2027 though.

Part of the problem is that heat pumps aren't really well suited to a use case where you frequently have to bring a house up to temp in the way you're describing. If you have a big overnight set-back and then the heating comes on in the morning, that will require much more heat output than constantly putting out enough heat to maintain temperature.

In a well insulated property, the greater efficiency from operating at low output temperatures outweighs the additional heat loss from no / a low overnight set-back. In a poorly insulated property, the optimum set-back is higher and the efficiency at that optimum point is also much lower because the heat pump has to operate at higher temperature in order to ramp up the temperature.

I don't know if they are available in North America, but in the UK we have hybrid systems available that use heat pumps for 80% of the annual heat load and gas for peaking / ramping. OpenTherm gas boilers can be retrofitted to be controlled in this way so you only add the heat pump. An air source heat pump driving a hydronic / radiator system in this climate can serve 80% of the annual load with a unit sized at 55% of peak heat load. Different climates will have slightly different numbers but it shows the power of a hybrid system as you save a lot on HP capex and also maintain redundancy.

The advantage of this system is that the failure-mode of an incorrectly sized system is an efficiency penalty rather than not being warm enough, the same as an incorrectly commissioned or sized gas system. (Most gas systems are not optimally sized or configured and are delivering 5% to 10% less efficiency than they could).

I don't know if these systems are available in ducted air configuration for the US market though.

London as well, or at least broke even. (Although of course this is complicated to assess and contested).

Same reason, all infrastructure was either already there or usable after (the Olympic stadium was sold to a football team).

Generally the larger a city is, the better able it is to host an event like this for obvious reasons.

I think this is a dumb idea, but come on, all prosecutions are retroactive.

There's a policy decision to cover as much as possible of the operating costs of the network from fares rather than government funding. The operating costs of UK trains per passenger-km is actually pretty competitive to European comparators but many countries fund a large part of the operating costs of their train networks from general taxation.

The heavy forged sections of a pressure vessel are really thick and there is a limit to how thick a single weld can be using conventional techniques. So you have to do many passes. Each one of those requires bringing the temperature of the massive forged sections that are being welded up to temperature, cooling it, and then x-raying the partial weld before proceeding with the next cycle. The actual time spent doing the weld is cumulatively not more than a week.

The tides are not constant but they are predictable.

The majority of tidal flow is during relative short periods of only a few hours. In order to harvest tidal energy, truly enormous volumes of reinforced marine concrete have to be deployed. The environmental consequences are massive.

There's a huge amount of North-South capacity being built as part of the holistic network design programme which will unlock a lot of capacity and substantially reduce curtailment.

We (an engineering consultancy, so not software but physical infrastructure) have an internal ChatGPT so that people can use it for work.

I find that it is quite good at answering textbook type questions and giving background on things. Basically a kind of supercharged search engine.

So for example, if I knew nothing about water treatment technology, I could ask it "what are the typical stages of water treatment for groundwater from a borehole?" and it will give me a good answer. Sometimes when you ask more specific questions, it will give some weird answers. It was convinced that desalination was already the main source of drinking water in a particular country, probably because there have been a lot of new desal schemes proposed and so the input corpus has a lot of associations between that country and desalination.

I just asked it a question on whether you could use nitrogen to cool a nuclear reactor (correct answer is yes, if it's enriched heavy nitrogen) and it gave an ok answer but didn't mention that N14 absorbs neutrons. This is pretty obvious but there is very little written about this idea in the likely input corpus so ChatGPT doesn't know this.

It cannot (and in fact, standard LLMs cannot because of how they architected) answer questions that require constructing counterfactuals or hypotheticals outside their input base. To note, from the point of view of an LLM, something which is covered in its input corpus is neither a counterfactual nor a hypothetical even if they are relative to the real world. So if nobody has ever written anything on the use of a particular technology for a particular purpose, no pure LLM will be able to answer questions relating to it. Other emerging AI technologies look like they will be able to do that though.

Plea bargains are heavily restricted in the UK and many of these cases were heard in Crown courts. I agree about getting rid of private prosecutions though.

There's broadly two reasons for this:

One, the evidence for it being a carcinogen remains relatively weak compared to many other substances we know of. It's in that category of chemicals where possible effects show up at the limits of detection for very high dose exposures. It's either weakly carcinogenic or that's just noise. Of course many chemicals, quite a few of them natural, are in that same class. There remains regulatory disagreement between the WHO and many other bodies on whether the evidence justifies a label as "possible carcinogen".

(toxicity to aquatic life is much better evidenced)

Second, it is indisputably much less carcinogenic and less toxic than almost every alternative wide spectrum herbicide.

It would seem disproportionate to me to entirely ban such an incredibly useful substance while we continue to live in a world with so many natural and artificial carcinogens for which we have much stronger evidence of danger and to which we are much more exposed. Nonetheless, it also seems reasonable to put additional controls on its use, restrict it to food production and other essential uses and discourage use for home gardeners and keeping city paths clear of weeds.

The Polish wholesale power price is above even what nuclear power costs to deliver in higher-cost UK and US markets on an LCOE basis (not that LCOE is a great way of comparing power costs but there it is).

PGE will finance it on-balance sheet, the way they would a coal plant. Most likely there will be US export finance for the elements coming from the US but most spend on big nuclear plants is local.

>The recent nuclear plants constructed in the west requires something like $5-15B above the market price in subsidies, of course depending on size, EPR at 1600 MWe or AP1000 at 1000 MWe. Would be interesting to know how they intend to solve that.

I'm not really clear what this means? All power plants require financing for their construction cost which is pretty definitionally the market cost of construction. If you mean how this will will interface with the Polish electricity wholesale market, well that market is already pretty dominated by a few large vertically integrated players settling trades with themselves. Presumably PGE will buy the electricity and treat it the same as their other electricity, they may receive a subsidy per MWh as well or maybe just avoiding the ETS costs of their current coal emissions will be enough to make the economics stack-up.

In many places (but not the US because of thermostat standards) HVAC systems are now typically inverter driven as well so that does remove some of the advantages of three-phase since any individual load is single-phase anyway.

The US also uses a different primary network configuration, typically running a three-phase network as main primary with single phase primary laterals. The pole-mount single-phase transformers then turn this single-phase into split-phase LV for consumer use. One consequence of this is that adding three-phase to a property that doesn't have it already is really hard - you need to upgrade the LV service connection, the transformer, and the MV lateral (since the MV lateral is only a single phase). Compare that to the European system which has three-phase distribution transformers and then runs three-phase LV past every property. In some places like Germany, the standard is to provide three-phase to every property, in others like the UK, standard is single phase service connection but... it's easy to add three phase since the other two phases are only a few metres away, I understand the Dutch standard is to run all three phases to the property but only connect as a standard (you have to pay for the upgrade).

I think in both cases, for urban and suburban areas it is standard to run the MV feeder as a normally open ring so that in case of a fault in the primary, parts of the system can be run from the other end of the ring by remotely operated automatic breakers. What I don't know is whether US systems do that at the level of the main primary only or also on the laterals.

The latest quantitative risk assessment of hydrogen in a domestic context is that slightly greater explosion risk is outweighed by the slightly lower fire risk. Hydrogen has a wider explosion range... but most natural gas explosions are from small leaks accumulating basements or low spaces in houses which hydrogen won't do. It could instead accumulate under the roof but roofs are almost never sufficiently gas-tight to hydrogen to allow for substantial accumulation.

Also, many leaks are in the mains or services under the road. Natural gas will flow along the outside of the pipe and through the soil and end up in the basements of nearby buildings. Again, hydrogen would not do this, it would diffuse up through the soil and disperse in the atmosphere.

The big change is to boiler enclosures. These are currently designed to limit voids sufficiently to prevent natural gas explosions which require a minimum cell size of a meter or so to explode (regardless of concentration) rather than deflagrate. That same size for hydrogen is about 5cm so that is the largest acceptable void within the boiler enclosure which requires re-engineering of the way parts fit together and the use of non-h2 permeable foams and plastic spacers to avoid unacceptable voids.

There are no "EU citizens" only citizens of EU member countries. None of those countries have freedom of speech as expansive as Americans but Americans in practice also don't have absolute freedom of speech.

1) Certain speech such as "shouting fire in a crowded theatre" has long been considered illegal.

2) The US has much more expansive laws about "conspiracy to..." which make it illegal to have certain conversations.

Oh, those don't count? Not real speech. Sure, why not.

3) Most people will experience very real economic consequences for a very wide range of speech. We're not all yeoman farmers entirely independent of paid employment.

That presumably doesn't count because only governments can restrict liberties? Well, have it your way but I would regard losing my job due to speech as a pretty severe restriction on my liberty.

Not in practice, no. Companies were provided with a regulatory position statement from the EA that they would not usually be prosecuted if they ran out of treatment chemicals due to something that wasn't their fault. In fact, there never was a shortage due to either Brexit, Covid or a combo and this was never used.

To be fair, while all of those things are true (and in fact the poor state of many rivers is more due to farming and to fully consented but still high-nitrate effluents from waste water treatment than to CSOs) the industry has really not even bothered to defend itself here. It's like they're just cowed by the criticism.

Nobody will build a heat-pump system with an on/off control system like that because the performance will be awful. Certainly not an air-to-water system.