• 0 Posts
  • 27 Comments
Joined 1 year ago
cake
Cake day: July 2nd, 2023

help-circle
  • Four points:

    The profile of other is short spikes 5-100 hours a few times a year.

    1 year of delay is equivalent to 20 years of exclusively using fossil fuels for “other”.

    It’s not even obvious that adding nuclear reactors would reduce this because they’re so geographically and temporally inflexible. France has 63GW of nuclear capacity, <45GW of average load and 61GW of winter peak load with vast amounts of storage available via interconnect to hydro countries. They still use 5% gas on top of the rest of the “other” (which is about 10-25GW).

    5% of other from gas adds about 20g CO2e/kg per kWh to the total. Less than the margin between different uranium sources.

    Running 40% of the capacity 10% of the time puts your nuclear energy in the realm of $1-3/kWh. The list of ways of generating or storing 6% of your energy for <$1/kWh is basically endless.

    That’s about 4-8TW of capacity worldwide. 1kg of uranium is good for fuelling about 750W of reactor on a 6 year fuel cycle. Loading those reactors would require digging up all of the known and assumed-to-exist uranium immediately.

    Nuclear is an irrelevant distraction being pushed by those who know it will not work. You only have to glance at the policy history or donor base of the politicians pushing for it in Sweden, Canada, Australia, UK, Poland, etc etc or the media channels pushing it to see how obvious it is that it’s fossil fuel propaganda.

    It is obviously obviously true that it’s a non-solution. It fails on every single metric. All of the talking points about alleged advantages are the opposite of the truth without exception.






  • well no storage can be 100% efficient but you are correct that thermal storage is very efficient if you want a thermal gradient to leverage for heating (cooling as well)

    If I have a room, and I want it hotter than outside now, and hotter than outside later, then putting an insulated box in the room and heating the stuff inside the box, then adjusting the lid to heat the room at the rate I want is 100% efficient. There is no loss eitber in practice or in principle nor any mechanism for one. This is true so long as I want all of the heat, even if I stored high grade heat and run it through a heat engine to make work before heating the room with low grade heat (in which case I might even call it a coefficient of performance of 1.3 or “130%”). I will never match the COP of a similarly engineered heat pump if all I want is low grade though, so in this sense “efficiency” is <100%.

    Carnot batteries (where I have a box but don’t want heat now or later but do want work) are quite inefficient (10-50% + a time based loss that only becomes negligible at the GWh scale) , or thermal storage in unheated environments (time based loss) are much less efficient.

    A separate heat and cold store from a heat pump feeding a combined heat and power generator is another variation (where a COP might come close to or exceed 1).

    F=ma is a bit of a thought terminating cliche (as well as being poor communication and missing a term). E=Fh=mgh. As per my link there are plenty of suitable hills and gullies over about 90% of where people live. A human made structure to lift will always be questionable.

    I guess it depends on what you mean by rare long duration events but yes one can imagine a situation where the burning of hydrogen is justified on an energy needs basis

    A handful of hours of storage (3-12) can pretty trivially meet loads 90-99% of the time. The remainder tends to be events that are 50-200 hours. Pumped hydro and non-round-trip storage (such as delaying EV charging, overprovisioning an industrial drying step and running it when electricity is cheap, direct ammonia electrolysis for fertiliser during high production times, or storing domestic heat in a pond for winter) can cover most of these.

    For the remainder (odd once-in-a-decade weather events or major infrastructure failures) the duration is even longer (100-1000 hours). One strategy is to just keep fossil gas generators around because 100 million tonnes of CO2 emitted and 1100 tonnes of CO2 removed that month may be easier than 0 and 1000. Another is to make something with electricity to burn (which could involve an electrolyser and could involve hydrogen gas storage but does not have to).





  • You’re just sharing propaganda. Those 100 companies cannot pollute without your money and consent. If everyone gets out of the car it no longer matters that the footpath is gone, you can walk on the street. The beef industry can’t use 50% of the land and emit half the methane if noone buys red meat.

    Chevron and Tyson foods are responsible and you are responsible. They will never step up and they will always use the power you give them to do evil, withhold it and show those around you that it can be done. The message you are spreading is both disempowering and deflecting blame.


  • There’s a difference between those in control of the system assigning blame to the peasants to avoid consequence, and owning your own share of responsobility.

    If you drive or otherwise consume oil and you don’t have to, you are at fault – but so is Shell for digging it up and destroying the tram. You are also at fault for giving them money, but so is Chevron for using that money to bribe the government.

    Owning your personal contribution, minimizing it, and more importantly, showing others how is praxis.

    Buying oil is a form of direct action helping the fossil fuel industry. So is driving because you make being outside a car just a little more unpleasant and dangerous. Buying a big car is even worse.

    The only myth worse than your carbon footprint being the only thing that matters, is the idea it doesn’t matter and some nebulous “them” needs to fix it.


  • It’s not a problem insofar as it costs more than what we are doing now.

    It may not happen because renewables and batteries are on such aggressive cost curves that it may be better to just store energy locally or produce more (and thus generate flexible high energy cost economic activity on top of the current energy demand that can happen whenever).

    Transmission and distribution currently costs in the ballpark of 3-7c/kWh. Longer distances will drive this up. Overnight-scale storage will drive it down (allowing it to run 24 hours a day at x watts rather than 4 hours at 6x watts).

    Solar energy is 1-6c/kWh. Overnight-scale battery is 2-7c/kWh. If you can rearrange your manufacturing so you do the energy intensive bit on a cheap machine on a sunny day and do the labour intensive bit on expensive machines in winter, you won’t consider transmission. If you can’t, you’ll weigh transmission against moving your factory to western australia or morocco or texas. Many processes have a drying or a reduction (removing oxygen with electricity or chemicals made from fossil fuels/electricity) or heating step that fills the first profile.

    End result is there will be a mix with countries that have less seasonal variation having an advantage in industries that are less flexible (because hitting the worst-case load will require less infrastructure), and countries with more seasonal variation having a huge advantage in flexible industries (as their winter heating bills will subsidize the free summer solar). Transmission will play a role too (but how kuch is uncertain).


  • Thermal storage is 100% efficient if you want heat. And with a pond or swimming pool sized reservoir and adequate alumina/silica based insulation losses are miniscule even over months. This is why production is going from effectively zero to hundreds of GWh with the factories being built now – the second 1 Joule of surplus solar is cheaper than 1 Joule of gas, it will replace all new industrial heat (presently this is limited by distribution costs). For work, a carnot battery is definitely competitive with hydrogen.

    PHES is perfectly viable almost everywhere https://re100.eng.anu.edu.au/global/ Although likely not worth building anymore as by the time it is actually needed all-abundant batteries may be cheaper.

    Electrolysis (as much as it is vastly overhyped and shoe horned into spots where it is idiotic) is a decent option for rare long duration events. Probably in the form of feed stock for chemical use having a month of buffer to reduce production costs and selling that to CCGT plants for the week or so every now and again that the electricity is more valuable than ammonia or ethylene or whatever.





  • In the 19th century the fossil fuels justnlying around might have been more accessible (but at this point most of the world lived without them), but since the middle of last century it has been concerted effort to externalise the costs and widely documented conspiracy and violence used to destroy alternatives with externalised benefits.

    Electrified rail (even if running on coal) uses a few % of the fossil fuels of trucks + roads, but top-down decisions by governments on the take were made to dismantle rail.

    Same with trolley busses and trams.

    Just building houses slightly taller and closer together reduces oil consumption by about 50%, but that was literally banned because it makes everyone owning a car impossible.

    Wind + pumped hydro has been an option since the 40s (much cheaper than coal + lung disease), and would have come down the cost curve with even a tiny fraction of the subsidies fossil fuels get. The first large scale wind farm was abandoned because it cost 60% more than unfiltered, acid-rain-spewing coal as if that was a failure rather than an overwhelming success.

    Trillions were spent securing oil. This isn’t paid back at the pump though.

    Solar thermal has always been a viable option for low grade heat everywhere and was proven viable for mechanical work in 50% of the planet in the 1910s. Coal soot makes it a lot worse.

    The ones holding the deeds to the coal mines and oil wells don’t murder, send armies, fund coups, buy the entire media, own most major political parties in the global north, purchase and dismantle transit systems, and strongarm universities because their product is better on technical merit.




  • What you’re after is an LCA of a specific instance of new technology (which attempts to measure the sources of harm in context) rather than a context-stripped summary of a complex subject drawing arbitrary lines designed to create a bad faith talking point. Anyone reducing it to a single number is making a bad faith propaganda point one way or the other. You won’t find any credible version of it because it’s not a credible exercise.

    The uranium that feeds the canadian project (excluding the historical tens of thousands of native deaths from intentional waterway poisoning) is harmless compared to what is happening in Arlit or Adapa (the harms of which are just beginning and are actively covered up). All estimates (by anti-nuclear advocates or by nuclear shills) of chernobyl are poor. Arbitrarily excluding santa susanna or windscale or mayak is done without reason. The risk profile of a 200kW wind turbine is vastly different to a 3MW one or a 15MW offshore one. Utility solar is nothing like rooftop. Countries with mandatory working at height safety equipment have vastly different risk profiles than those without.

    Acknowledge that the harms are low for the bottom four options if they are done properly, then actually enforce doing them properly rather than using it as ammo to justify the horiffic (and rising) pollution from uranium milling, mining and plutonium extraction whilst exaggerating having one person die in an entire country’s utility solar program. And also treat mining for rare earths for either magnets or obsolete USA-based thin film solar or burnable neutron poison the same way holding both to the exact same standards per unit of energy.

    Treat all waste from all options the same way (non-recycled waste must be only a few dozen kg per lifetime of energy and it must be permanently dealt with before profit is disbursed).

    Treat danger from all options the same way. Disaster cleanup (be it oil spills or radiation or a dam burst) must be fully collaterised with no liability limit from assets that won’t crash if something happens.