Yeah just watch his videos. He’s not beholden to one builder or one neighborhood he’s all over the place and inspects on dozens of builders.
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iocase@lemmy.zipOPto
You Should Know@lemmy.world•YSK refrigeration can be done using heat, which can then power district cooling systems.
4·11 hours agoI’m going to have to fundamentally disagree with you here. Waste heat recovery boilers have existed for generations, are extremely well understood, and are extremely common. They’re one of the most efficient designs out there for power generation and they can be adapted to work as combined heat and power stations with no loss to the power generating efficiency of the primary boiler or gas turbine.
District heating water at 105⁰C can provide both heat and the energy needed for absorber chillers. Adding the district heating/cooling water tubes after the HRSG isn’t free, yes, but it’s almost free from a capital perspective compared to building a new plant or the cost of a pipeline network + furnaces and ACs in every single home. Especially when you already need to burn energy anyways… 50% of the cost of power is fuel, so if you can reuse waste heat for heating and cooling you reduce electrical demand and make low enthalpy heat into something useful.
Look up combined heat and power plants if you want a reference for what that setup can look like.
Oh yeah you’re right lol I forgot about those somehow! I laughed when he checked like 8 houses in a row and they all leaked.
iocase@lemmy.zipOPto
You Should Know@lemmy.world•YSK refrigeration can be done using heat, which can then power district cooling systems.
2·13 hours agoIt’s not a bad idea it’s been used repeatedly on earth, its just the incentives never lined up to make district heating and cooling a thing everywhere. Sweden and old Soviet cities use district heating since it’s really cheap at scale. Dubai uses district cooling (with electric chillers though) to cool pretty much the whole city for far cheaper than every building having its own rooftop system.
In North America we take the most insane approach of every home having its own miniature thermal plant (furnace) and electric air conditioner. District heating and cooling is a hard sell because trenching in new insulated pipes would be extremely disruptive and expensive compared to if they were already in the ground prior to this. If you could somehow convince everyone to be ok with the disruption and also to have 80% or more of the city hook into the system as subscribers, it would be vastly cheaper than natural gas heat or electrical cooling.
Parts of Ontario use great lake water for cooling, so district cooling is a thing in parts of Canada.
There still are district systems in north America though they just tend to be university campuses, where all of the buildings and dorms are cooled or heated with one central combined heat and power plant.
One of the biggest benefits of district cooling is elimination of one of the biggest drivers of the urban heat island effect: AC exhaust. Every working AC unit makes every other AC unit near it work harder. A district cooling system pipes everything back to one plant where that heat is rejected out the top of a stack.
Thermodynamically it shouldn’t just reduce AC’s contribution to the heat island effect, it should also make buildings themselves into heat sinks helping to cool the city itself as thermal energy tries to migrate into buildings where the district system soaks them up and pipes it away to the cooling plant.
iocase@lemmy.zipto
Work Reform@lemmy.world•Don't we like video games to relax after a hard day's work?
20·16 hours agoThat’s roughly what I pay and I just got two retroactive 3% raises and a massive increase in my benefits thanks to my union. My employer wanted to cut people or freeze pay and the union made them back down in everything. We got everything we wanted and didn’t need to compromise… Worth every penny in union dues. I’ll have a cheque for a few thousands dollars mid July now.
Unionize!
iocase@lemmy.zipOPto
You Should Know@lemmy.world•YSK refrigeration can be done using heat, which can then power district cooling systems.
4·13 hours agoOh yeah I forget most people have no idea… Sorry about that.
What I’m saying is we’re throwing out fuck tons of free cooling and heating that we could otherwise use. Every house in North America could be cooled and heated with no extra fuel burned from the same power plants and industrial processes that supply them? Roughly speaking?
Why would you pay for electricity for cooling when a capital expense can get you that for essentially free? You don’t have to make the plant burn more fuel, you don’t have to interfere with how the plant runs, you can just tap off low grade heat and make chilled water to supply a town or city (Dubai uses district cooling if you want an example, although they use electric chillers)
This isn’t theoretical. It’s already used on earth and it works really well.
What I was trying to show with my numbers is the heat energy you need to burn for an equivalent amount of cooling isn’t that different compared to a electrical compressor chiller with a CoP of 3.5. 83MW of heat energy burned vs 60MW of heat energy for electric chillers. The difference is you don’t need to buy 83 MW of heat, whereas you need to buy the 20MW of electrical power (which took 60MW of heat) to run your chillers.
My other numbers were to demonstrate the eye watering amount of energy we discharge out of flue stacks and out of heat exchangers into rivers or lakes… If it’s hot enough, that energy can be used for heating and cooling but currently it goes up a stack.
iocase@lemmy.zipto
News@lemmy.world•JetBlue flight hit drone while approaching JFK airport, FAA says
5·16 hours agoYeah seeing as I’m not my parents neighbor, and I’ve also seen the video where he was above the cloud layer that day, you would need to ask him how he did it.
Pre seasoned lips
👁️👄👁️
iocase@lemmy.zipto
News@lemmy.world•JetBlue flight hit drone while approaching JFK airport, FAA says
3·22 hours agoMy parents neighbor (irresponsibly) flew their mavic 2km up above their naighborhood
He talks about this in his videos where he’ll see the same problems in half the homes in a neighborhood because neighbors talk to each other and recommend him
Edit: just watch some of his videos you won’t have to spend much time to see what I mean. It’s systemic…
You should look up CyFy on YouTube. He does residential building inspection in Arizona and the build quality is appalling. Broken trusses, lacking insulation, roof leaks, stucco with exposed wire backing on top of literal cardboard for structure…
Cracks in the sinks and tubs, walls so horrifying out of square you wonder how they managed to fuck it up that badly. Unlevel floors with humps or saddles. Tiles misaligned so badly you can take a strip off your foot without realizing.
There’s always multiple things from the above in every house he posts… And it’s not just one house, it’s all of them. Literally all of them… They deny, delay, defend the shit out of warranty claims and at least in Arizona hope you close and don’t raise a fuss before hand.
iocase@lemmy.zipOPto
You Should Know@lemmy.world•YSK refrigeration can be done using heat, which can then power district cooling systems.
51·3 hours agoLet’s assume we need 100MWth of cooling capacity. At a CoP of 5 (generous case) we need 20MWe of power to move 100MWth (120MWth total with our electrical input converted into heat eventually as well)
Comparing that to absorber chillers: A single effect absorber at a CoP of 0.4 needs 250 MWth of heat energy at or above 90⁰C. If you go dual effect you can get 0.9-1.2, but need higher grade heat. I’ll do the worst case for now.
For reference, 250MWth is roughly what goes up the stack in a 125 MWe plant (hilariously tiny plant. Might run a remote community and be a portable turbine generator or two on a trailer? I’ve worked on gas compressors with higher nameplate capacities than that by miles)
A 1GWe coal plant at 33% efficiency burns 3GWth of heat energy and discharges 2GWth up their stack. That’s 2 GWth you have available as waste heat. By definition it has to be vented to atmosphere or to water at the condenser. That’s a lot of already-paid-for heat being literally thrown out.
If you count cooling efficiency using just the thermal watts you have to burn at the powerplant for the electric cooler to move 100MW of heat:
20MWe / .33 = 60 MWth needed to generate it.
If your electric chiller is a more reasonable CoP of 4:
100MWth heat moved, takes 25MWe.
25MWe at 33% efficiency, is 75.75 MWth of heat energy burned at the power plant to make 25MW of electricity.
If you used a dual effect absorber at 1.2 CoP:
100MWth cooling with 83MWth of heat energy at 170⁰C.
What these two numbers show is we can move 100 MW of thermal energy with an electric chiller by burning 60MW (or 75.8MW) of heat we then turn into electricity from a power plant, or 83MW of heat that already was burned, if we steal heat from the flue gasses and use an absorber chiller. The raw energy input to do 100MW of cooling differs by only 23 MW, so an absorber is in the same order ballpark still.
What’s important to note here is the energy needed to run an electric cooler is $money$ while the energy to run an absorber is waste heat going up the stack… These are used on earth already BTW just typically as a combined heat and power plant for universities or government/company campus. There’s no reason you can’t also apply that to an entire city.
For example, Aarhus University Hospital, Denmark uses a 3 MW absorption chiller powered by 105 °C district heating water. It consumes about 4.3 MW of heat to produce 3 MW of cooling, while simultaneously returning useful heat to the district heating network. It’s operated alongside electric chillers so the most economical option can be chosen depending on electricity prices
Crucially you don’t need to oversize your power grid for a summer heatwave peak, when your power lines are hottest (highest resistance, expand, droop lower and maybe short out on trees) so you can instead use literal waste to cool a city instead. Cooling tends to be ⅓ the amount needed for heating roughly, so you a home that needs 12kW of heating roughly needs 4kW of cooling.
2GWth of cooling capacity at 4kW per home is 500 000 homes cooled with waste heat. Of course this is assuming perfect efficiency, but it illustrates my point. District cooling typically uses 1-3% of the cooling nameplate in electrical demand for pumps afaik, so a 2GWth cooling system needs 60 MWe of pumping. To achieve the same cooling with electric chillers you need 571 MWe (assumed 3.5 CoP) just for chilling, consuming more than half of the power output of our 1GWe plant.
iocase@lemmy.zipOPto
You Should Know@lemmy.world•YSK refrigeration can be done using heat, which can then power district cooling systems.
71·1 day agoSo my background is in instrumentation and process control as an engineering technologist. In my country that means I can do limited engineering within my scope of practice, part of which extends into thermodynamics, balance of plant, steam enthalpy calculations, sizing and speccing heat exchangers, boilers, condensers, compressors, turbines, valves, and the controls for all of it.
I’m very familiar with all of this, so I can tell you from experience that these absorber plants can be bolted on after an economizer (in the case of a single effect) or you can supply higher grade heat if you’re willing to sacrifice part of your economizer capacity in exchange for cooling in order to get high enough generator temperatures in a dual effect absorber.
Otherwise you have to trim with electrical resistors to get your preheated water up to the generator temp to run the absorber plant (also viable. Bolt on after the economizer and use a small amount of electrical heat to finish the missing heat to run the generator)
The 30-40⁰C you’re referencing is the condenser temperature at an electrical plant. That’s not the flue gas temperature which can still be quite high depending on the plant, in the range of 80-170⁰C depending on how efficient their design is.
Other processes like cement kilns, glass making, garbage incineration all can produce the temperatures you need for dual effect absorbers.
This isn’t theoretical, you can find these absorbers already in use at combined heat and power (CHP) plants running university campuses and government/company campuses. They are already used for limited district cooling for these places to accompany heating.
The overall benefit is they are extremely low impact on the environment since LiBr is non toxic, isn’t poisonous, doesn’t deplete the ozone layer, doesn’t contribute to GHG emissions like released butane or isobutane emissions would. It doesn’t produce toxic gasses or use high pressure or exotic temperatures or materials.
It also reduces electricity demand for cooling massively. An absorber chiller runs on practically unusable waste heat that’s too low enthalpy for any other use. You get free cooling and the plant is very low maintenance, ingests waste heat that would have gone up your chimney or flue, and spits out cold water. What’s not to like?
The best part is they also work extremely well with renewables making them natural partners if you have a thermal sand battery paired with it. District heating and cooling can run from one very simple plant, which is going to be more and more important as our climate gets more hectic from global warming.
iocase@lemmy.zipto
Technology@lemmy.world•Ford rehires ‘gray beard’ engineers after AI falls shortEnglish
2·1 day agoYup. Their most useful attribute is a shared class consciousness among the ownership class.
iocase@lemmy.zipto
Technology@lemmy.world•Ford rehires ‘gray beard’ engineers after AI falls shortEnglish
12·1 day agoExecutives arent leading a company because they’re smart…
iocase@lemmy.zipOPto
You Should Know@lemmy.world•YSK refrigeration can be done using heat, which can then power district cooling systems.
9·1 day agoYeah that’s the big thing. Absorption chillers can work on marginal heat that isn’t useful for much else except maybe boiler economization. They run at low temperatures but aren’t efficient.
If you have a neighboring cement kiln that exhausts at 300⁰C, that’s perfect for use in district heating or cooling?
It’s basically a heat recycler for trash heat you might throw out anyways.
iocase@lemmy.ziptoMicroblog Memes@lemmy.world•Whoops, tee hee. Let's all just forget about that little mistake.English
143·1 day agoIf Monsanto can hide the fact that they paid off scientists to say Glyphosate is safe for 30 years when they knew it caused cancer, I don’t know whether I can trust that. I’m sure they have ways to hide recalls to deny, delay, and defend the process…
Yeah big agree. Gold was also easy since it was a lingua franca commodity, instead of maybe a modern version being a basket of commodities backing a currency.
I understand the implicit reason they dumped the gold standard. Your industrialized economy can grow a lot faster than you can mine new gold out of the ground. Deflationary pressure meant there was pressure to print more paper dollars than there were gold backing them to stave off inflation. France calling the US’ bluff on gold backing by repatriating their reserves certainly didn’t help at all.
The big benefit though is like you said. You can’t fuck with gold the same way as fiat. You can’t magically make more, much like the current Iran conflict is going to crash the world economy because a bunch of idiots in the US think they can print oil…
Knowing you can’t print gold is supposed to be a stabilizing influence on a country’s fiscal policy. Don’t fuck with your own currency lest you ruin it, cause a bank run, and debase it to being worthless and need to start over or borrow a foreign currency’s stability.
A basket of commodities could be the way forward though… That’s basically what the Petro-dollar is informally. But if you made some kind of international trade currency that was basically a warehouse receipt for X amount of gold, silver, wheat, barley, oil, sulfur, ammonia .et, that basically all countries use, maybe that would work?
Digital currencies like Bitcoin or other speculative assets just don’t work long term…
iocase@lemmy.zipOPto
You Should Know@lemmy.world•YSK refrigeration can be done using heat, which can then power district cooling systems.
91·23 hours agoBecause if you can find a free or cheap heat source that you’re going to vent to atmosphere up a flue, or dump into a river/lake/evaporation you can make cooling with it for almost no marginal cost once you’ve made the capital investment, plus with very little moving parts. An absorption chiller can be the last useful process on your exhaust heat before venting to the environment and all it costs is maintenance and a few small electric pumps.
You use the kiln exhaust gasses which are waste heat. You don’t need to ask the kiln to burn hotter or with more flue gas mass flow. The absorption chillers are already used in district cooling systems on university campuses and government offices. Usually where you have a combined heat and power unit, so you have your own heat source.
Theres nothing stopping you from using any viable heat source though… Plus single effect chillers run on 90°C. For waste heat that’s literally free heat why not as opposed to paying for power? Double effect chillers need 170⁰C heat for their generators, so a cement kiln could provide the heat needed to run the chillers using their exhaust gasses.
A district heating/cooling setup using low grade waste heat around ~150⁰C, plus a soapstone battery (resistively heats soapstone sand when renewables are over producing and need to either sell at any price or shut down) could provide both heating and cooling with nothing but waste heat and a thermal battery that tops up using over productive renewables.
For the same sized electric chiller, you can use 99% less electricity (you just need low pressure low velocity pumps for moving liquids around the absorption chiller) and the heat can come for free or cheap elsewhere.
Most large heat consumers try to reuse their own heat, and if they can’t they pay to discharge it into lakes, rivers, or evaporate water. If instead a district cooling company paid them for their heat they can turn a cost center into a profit center?
I’m summary, absorption chillers work on heat that’s so low temperature it’s almost useless for anything except boiler economization. That’s the value proposition.
Edit: I keep adding more to this comment as ideas flow. Sorry for the rapid edits.




It’s like if my ISP decided I needed to drive to a local office in town to pick up my data packets. WTF!?