The reliability aspect of this self-contained system is quite impressive. Over the course of my life, I've personally experience many power outages, water outages, cell service outages, internet outages, etc. but never a natural gas outage.
BasilPH 9 days ago [-]
It's definitely impressive. However, natural gas outages do happen. For example Winter Storm Uri in Texas led to gas outages.
Sadly, the outages and possible the loss of life connected to it could have been prevented if the gas companies hadn't fought back against stricter weatherization rules[^0].
> they made recommendations to the Railroad Commission to implement weatherization rules on the natural gas supply chain because there had been water coming up from the formations — it's called produced water, it's naturally occurring — and it was freezing at the top of the wellheads and restricting gas flow both at the wellheads and in pipelines.
And yes, the Railroad Commission is not in charge of trains, but oil and gas in Texas.
Also, a contributing factor to gas compressor station outages in Texas during Winter Storm Uri was ERCOT (Texas' electric grid operator) load shedding without knowing they were shedding gas compressor loads. This led to reduced gas supply available for generation.
> When load is being shed involuntarily, customers designated as “critical load” can be exempted. Critical
load is typically demand from entities, such as hospitals, for whom a power interruption could be
extremely costly. To be deemed as critical, the customer must first file paperwork. The winter storm
revealed that certain parts of the natural gas supply chain – such as natural gas compressor stations –
were not designated as critical load. In consequence, their power was cut, thereby reducing flows of
natural gas along the state’s pipeline network and contributing to partial and complete derates at
multiple natural gas power generation units. The loss of their output in turn necessitated further load
shedding, potentially creating an unstable feedback loop. This represented a single point of failure in
the energy supply system.
every hospital I’m familiar with has its own backup power generation. Sometimes diesel so they can fully island off the grid for a while (but unsure about water & heat source). And with roll-up generator hookups+contracts if that fails.
Those should be the first requirements before being able to be deemed critical.
Heck, I’m familiar with some orgs that sell their backup generator capacity to be on-call to the grid in the event of supply shortage. To them it’s a profitable load test that reduces the risk of outage.
briffle 9 days ago [-]
My local hospital gets a deal from the local power company that they kick on their generators at peak demand times, and the power company pays them handsomely for it. The hospital gets to test their Emergency power works as expected, and the power company reduces their load by a few Megawatts for a few hours.
iphoneisbetter 9 days ago [-]
[dead]
gorkish 9 days ago [-]
> Those should be the first requirements before being able to be deemed critical.
Strong agree; however, it would be highly unusual to find that any facility that knows to file critical load paperwork has neglected this, so I'm not sure that it would actually do much other than inconvenience the process.
short_sells_poo 9 days ago [-]
You pointed out something I've never considered and I feel the same. Gas networks seem to be very reliable and crucially safe (given the contents are pressured and flammable).
Yea but it’s coupled with an incredibly leaky distribution system.
It would be so great to regulate fixing that instead of getting rid of it entirely.
matrix2003 9 days ago [-]
Maybe someone can correct my logic. As long as we are drilling for oil, wouldn't the natural gas need to go somewhere anyway? I believe it gets flared if not used.
ie - we should responsibly use all the excess natural gas rather than flaring it?
rootusrootus 9 days ago [-]
Leaking methane to atmosphere is considerably worse for climate change than flaring, I suspect that's the point being made.
matrix2003 9 days ago [-]
Yeah. That's what I struggle with. However, I guess increasing dependence on methane is not something we want to increase (to encourage more fossil fuel usage).
laurensr 9 days ago [-]
In the sixties, hexavelent chromium was used as a rust inhibitor in cooling towers in a Hinkley PG&E compressor station. It caused ground water contamination affecting the health of many.
This is interesting, especially for me as one of the intrastate pipelines on the map crosses through my property.
However, the article doesn't say what the "PIG" is (but talks at length about how the "PIG" is "launched" or "received"). Wikipedia says it's basically a passive device that gets inserted into the pipeline and pushed along by the pressure to clean or inspect the inside of the pipe.
engineer_22 9 days ago [-]
I dont know about gas industry, but perhaps this will shed some light.
In the drinking water industry the pig is a large foam block that is shoved in the pipe, and the weight of the fluid behind it drives it along. It is used to physically loosen the accumulated debris on the inside of the pipe. This debris concentrates behind the pig, and when the pig arrives at it's destination you remove the pig and allow the fluid (and debris) to discharge to waste for a period of time until the fluid runs clear.
Some advancements include "ice pigs" which is just crushed ice. The advantage of an ice pig is you can hook up to a fire hydrant and pump the ice in, no need to access the mainline pipe itself. An ice pig will also disintegrate on its own, no need to remove it, just allow it to flow out of a downstream hydrant, any ice left behind isn't a problem.
prometheus76 9 days ago [-]
It's very similar in the natural gas industry. The "dumb" pigs are a piece of foam that is shoved into the pipe at the "pig launcher" and they use air pressure to push the pig through the pipe, where it is then caught in the "pig catcher". All the debris from fabrication of the pipeline is scrubbed out by the pig and removed at the pig catcher.
Nowadays, they also have "smart pigs" that have sensors to detect gouges, dents, pipe wall that is too thin, etc. as the pig moves through the pipe, so that repairs can be made before the pipeline is filled with gas.
Scoundreller 9 days ago [-]
Pigs are also used to separate products. Lots of pipelines can switch between different products and different grades of products (e.g. gasoline of different specs required for different areas, kerosene, jet fuel, diesel).
I’m guessing those are usually “dumber” ones.
fuzzfactor 9 days ago [-]
In the very long fuel pipelines a foam pig can not make the whole journey to the cargo's delivery point, so the different grades of gasoline, diesel, and blendstock are pumped sequentially back-to-back with no physical separation, resulting in many barrels of intermediate off-spec fuel that is designated transmix and segregated upon arrival.
Inside the tank terminals I had to witness and certify the pigging after each parcel loaded, when one chemical was done and the line needed to be cleared and volumes accounted for before filling with a different chemical. Among many other more or less toxic things. Measurement training was not easy in the full-scale industrial environment but you can't really lead as well in the micro-scale activities without it.
pfdietz 9 days ago [-]
I believe pig is a word, not an acronym, although maybe it's a bacronym now.
> Some early cleaning "pigs" were made from straw bales wrapped in barbed wire[4] while others used leather.[5] Both made a squealing noise while traveling through the pipe, sounding to some like a pig squealing,[6] which gave pigs their name.[7][8]
That’s really slick and looks easy to use, good job!
9 days ago [-]
cdibona 9 days ago [-]
The smart pigs honestly look like a pigs snout flying down the pipe.
nobodyknowin 9 days ago [-]
Exactly. The old ones were basically passive cleaners. The modern ones are full on inspection tools with cameras, magnometers, etc.
We have a natural gas line running through one of our agency properties, and it was recently repaired due to the pig's findings.
Basically the engineers running the pig mark sections of the pipe that need physical inspection. The crews come out, dig it up, and repair or replace a section depending on how bad it is. Or do nothing if the engineers see that it's nowhere near as bad as they thought.
cdibona 9 days ago [-]
If you wanna see cutouts of a bunch of this equipment, a pig in a transparent pipe, and just happen to be in Oman, the petroleum development museum there is super.
Id imagine there's something similar in Houston, this stuff is legit fascinating.
DowagerDave 9 days ago [-]
One of my earliest memories when I started working in O&G many moons ago was seeing the hilarious daily report "Pig stuck in pipe". From a technology perspective it's an amazing industry, combining old-tech and human experience with some of the most advanced tech that can work in harsh environments similar to space.
londons_explore 9 days ago [-]
theoretically, compressing gas is energyless. Ie. you get back exactly the same amount of energy when decompressing as you got when compressing, so you should be able to do it with no loss.
Practically, that's fairly far from true for today's technology. Gas is so cheap that we're happy to waste a bunch of energy to make the plant cheaper.
ce4 9 days ago [-]
The compressor stations are alongside the gas pipeline network. These put in the energy needed to keep the gas flowing over long distances through the network.
Without those it would be just like a very very long garden watering hose that has a trickle of flow compared to a short one.
londons_explore 9 days ago [-]
I don't believe this to be the case.
The differential pressure from one end of a gas pipeline to the other is not 1800 psi - it is more like 20 psi. You don't repeatedly recompress along the pipeline length - you compress once at the start, and decompress once at the end.
The reason to use high pressures is because for a given pipe diameter (and therefore cost), you get far more gas transported at high pressures than you do at low pressures.
formerly_proven 9 days ago [-]
Most of the energy in pipelines is lost through friction inside the medium and friction between the medium and the inner wall. These are very much not reversible processes. Also the pressure differential is much bigger than you suggest. E.g. the pressure differential across NS1 was nominally around 110 bar (1600 psi) with an inlet pressure of 220 bar (3200 psi) and an outlet pressure of half that.
> You don't repeatedly recompress along the pipeline length - you compress once at the start, and decompress once at the end.
There are often recompression stations in pipelines precisely because pressure drops across the length, and on land it's cheaper to have those along the length of the pipeline than one really big one like NS1 had.
sveng 9 days ago [-]
Interstate or longer intrastate pipelines require compressor stations every 75-100 miles. The parent article mentions this under "Compressors". As another comment states, friction is the main reason.
djaychela 9 days ago [-]
It also means large storage tanks (known as gasometers in the UK) aren't needed. A couple of hundred meters of pipe at high pressure holds the same amount of gas as one of them.
squigg 9 days ago [-]
As someone else who grew up seeing these across the UK, it was never clear to me why they disappeared - this explains it perfectly, thank you
w1 9 days ago [-]
>> You don't repeatedly recompress along the pipeline length
Yes, you do. That is the primary purpose of transmission compressor stations. You may just lose a few psi per mile or something, but over the course of 100s of miles..
tomas789 9 days ago [-]
I don’t think that is the case. Surface roughness and directional changes are big losses. For example a single valve on a high pressure line can have a bigger pressure drop than 2 bars. So 160 km of a pipeline will drop a lot more.
tantalor 9 days ago [-]
Companies construct these stations along natural gas pipelines and use them to compress gas so it can continue flowing downstream to its final destination
HPsquared 9 days ago [-]
Expansion could only recover the "compression work done" if the pipeline between the two was perfectly insulated so no heat was lost.
happyopossum 9 days ago [-]
> theoretically, compressing gas is energyless. Ie. you get back exactly the same amount of energy when decompressing as you got when compressing
That's only true in a word with incomplete physics. Friction and drag exist, there's no sense pretending a process is imperfect because of them.
coffeeshopgoth 9 days ago [-]
As a chemical/petroleum engineer, this is a great little summary of how these stations work. Good find.
morninglight 9 days ago [-]
I think most people would agree with you. Electrical power outages are somewhat common, but gas delivery seems very solid.
Yet when selecting a home backup generator, most people opt for a gasoline powered generator and NOT one powered by natural gas.
mauvehaus 9 days ago [-]
There are probably two good reasons for this:
1) Getting natural gas plumbed to your generator is expensive.
2) If you're running this generator for an extended period of time, things have pretty much by definition gone to shit and aren't working as designed. You have a lot fewer dependencies to go fill a couple of jerrycans with gas at the nearest gas station (that has both gas and power to pump it [0]) than you have to restore piped natural gas service to your property.
[0] And if a gas station loses power, getting it hooked back up restores its utility to everyone, whereas restoring power or natural gas service to a home only restores its utility to the person living there. Prioritizing gas stations over private homes makes a lot of sense.
zrail 9 days ago [-]
Your second point depends on your threat model. Personally my threat model is a wind or ice storm taking down the aerial electrical lines in my area (SE Michigan). The natural gas lines are all buried and the pumping stations are powered by natural gas so are inherently more reliable.
If your threat model involves civilization deteriorating to the point where natural gas stops working then sure, a generator with fuel storage on site probably makes more sense. I'd argue that gasoline is the worst of available options though. Diesel and propane are much more shelf stable and typically more reliable than small gasoline engines.
ordu 9 days ago [-]
> a generator with fuel storage on site probably makes more sense
Storing fuel is dangerous in general, but I believe that liquefied gas is more dangerous. It is more tricky. For example you need to store it in a ventilated environment, to prevent gas buildup. If you turned wrong nut you'll may be not able to turn if back due to pressure.[1] It can be treated safely, but it much more tricky that with liquid fuel.
With propane, there is also the problem of the vaporization rate being very low at winter temperatures. I've got a small 2500W (1850W continuous) dual-fuel generator that I had expected to be able to run off of a 20lb propane tank. It didn't work at all when I actually needed it (surprise!), and I ended up just running on gasoline and having to go out to get more. It has since been working fine off of 3 tanks teed together, although I still haven't seen middle of the winter arctic blast temperatures with that set up yet.
creeble 9 days ago [-]
You might need a horizontal tank.
Liquid Propane requires surface space to “gasify”, and more space the lower the temp. That’s (one reason) why propane “pigs” are horizontal cylinders.
Unfortunately, there aren’t many small horizontal tanks.
mindslight 9 days ago [-]
Yeah, I researched it after the surprise. Practically for as much propane as I use, it didn't feel worth it to look at larger tanks (there's a price jump, larger ones still have limited lifespan, and smaller is easy to transport/refill). Plus I already had several 20lb tanks kicking around, so teeing them together was the straightforward option.
Down the line I figure I'll be building some sort of generator "shed", and perhaps look at using the generator exhaust to warm the tanks. A loop from the heating system would positively solve the problem, but that feels like way too big of a circular dependency.
7 days ago [-]
billfor 9 days ago [-]
It used to be true that the pumping stations themselves were powered by gas, but this is no longer guaranteed because some have been replaced by cheaper electrical pumps.
Many people who use natural gas in the mountains of NC/TN right now are without any access because even the buried infrastructure there got destroyed.
devilbunny 8 days ago [-]
There's not very much that you can do against that particular threat model other than not live there, but one of the big reasons that the area is so popular with tourists is that it's easily accessible to most people (you can easily get to Gatlinburg or Asheville within a day's drive from pretty much anywhere you would consider "the southeast US"), it's pretty, and in summer you can escape the oppressive heat without having to go to the upper Midwest or the Rockies.
Massive landslides and floods will wipe out your natural gas lines, your propane tanks, your wind and solar generators, your battery backups...
zrail 8 days ago [-]
Sure, and now that their threat model includes devastating landslides they will probably make different choices.
userbinator 9 days ago [-]
Diesel generators are better than gasoline as the fuel can be stored for much longer, and has a higher energy density. Of course, the up-front cost is also higher.
rootusrootus 9 days ago [-]
That must be a regional preference. I don't know anyone that isn't a big institution that has a backup generator powered by diesel (and definitely not gasoline). Permanently installed home backup generators are invariably natural gas or propane.
Gasoline is a terrible choice in any case, it goes bad quickly if you don't stabilize it. The only time I ever see gasoline being used it's with little portable generators. Even then, I see a lot of people starting to choose propane instead now.
mannykannot 9 days ago [-]
IIRC, the big Texas freeze of a couple of years ago knocked out both pipelined gas and electricity supplies, and over a much wider area than just Texas, on account of the interdependence of both systems.
Of course, once you run out of gasoline or propane, you are once again dependent on the infrastructure.
zrail 9 days ago [-]
It turns out that was ordinary fraud[1] not a flaw in the physical plant. States with functional regulatory bodies don't have this problem. At most you get a situation like Michigan in the winter of 2019 where there was a massive fire at a primary storage facility and they asked everyone to conserve gas if possible.
I see this is developing news, and interesting in its own right, though without a clear resolution yet. Regardless, one only needs the outcome of the event to be aware of the possibility of a common-mode failure disrupting both electrical and pipelined natural gas supplies at the same time.
jmbwell 9 days ago [-]
As long as the flow of money isn’t disrupted, the system works as designed.
The most significant laws Texas enacted after the freeze — HB 3 and 5, SB 1015 and 2627 - mainly establish new funding for gas-fired plant construction, cut funding for renewable construction, and allow energy companies to raise rates on customers more frequently.
Observers will note that gas fired plants had the most unplanned outages, while renewable sources had the fewest. In any case, what matters is that the $9/kWh costs are duly distributed to the customers and tax payers, to the benefit of energy traders.
bob1029 9 days ago [-]
I recall the spot price of natural gas going through the roof leading up to the crisis. I would be less shocked to find out this was an intentional winding down of capacity for economic reasons.
zrail 9 days ago [-]
Gasoline generators are significantly cheaper. There are some tri-fuel generators that can run on gasoline, propane, or natural gas, but again they're more expensive.
A natural gas powered permanent standby generator is amazing for peace of mind but they're a significant investment.
Damogran6 9 days ago [-]
Propane has substantially less energy per unit mass than gasolene. In our RV, we have a gas generator and propane for the heater/fridge...Propane is MUCH better than batteries to run the Fridge as well.
4 LiFEPO4 batteries run our fridge for about 8 hours. two 30lb propane tanks would run it for about a week, and the 30 gallon gas tank just recharging the batteries to just power the fridge could probably go 2.5 weeks.
rootusrootus 9 days ago [-]
Solar is the answer. Propane fridges are incredibly slow to cool. Best thing I did for my RV quality of life was install a bunch of LFP and a few solar panels, along with a compressor fridge. I don't miss the old absorption fridges at all.
Damogran6 9 days ago [-]
I probably will when the budget frees back up, the ROI isn't there for the number of times a year we boondock completely off-grid.
bob1029 9 days ago [-]
I have more faith in my 2200 watt inverter generator than a typical residential standby unit.
If something goes wrong with a generac, you likely need a service tech to come out. If my portable unit acts up I have a 2nd new one in a box just in case. They're so cheap you can basically afford to keep one fresh for each disaster.
rootusrootus 9 days ago [-]
Love my little 2K watt inverter generators, but I don't think it's a good substitute for a residential standby unit. I can't get a 240V split phase generator that can be carried, that's the big thing. I could get past the time it takes to turn on the generator, but there's a good chunk of my house that won't run without 240V (unless I want to run extension cords everywhere, which I do not...).
bob1029 9 days ago [-]
Obviously the little inverter generators can't carry the normal load, but you can adapt to it. The biggest thing for most people is running their AC condenser.
A portable inverter AC unit (ideally a dual-hose unit) will pull ~1700w on the high setting. You can cool a solid 1000 sqft even in the Texas heat with something like this while also running your lamps/wifi/starlink/fridge/etc.
Combine with something like an EcoFlow battery, and you can actually shut it off completely while you sleep (and lock it up inside safely). Setting the AC to the low setting will reduce its consumption to ~400w intermittently which will easily run on a 2.5kWh battery all night. The other advantage of the EcoFlow is that you can temporarily run much larger loads than the generator is directly capable of. Really good for induction cooktops and getting your washing machine spin cycle up to speed.
zrail 9 days ago [-]
Inverter units are nice, those Honda engines run forever.
I've had my 26kW generac for almost two years and it's done several multi-day outages without issue. I just have my mechanical contractor come out and do the annual maintenance on schedule, keep track of the weekly self-tests, and otherwise don't worry about it.
rootusrootus 9 days ago [-]
I want one, but can't justify it. Probably be into it around 10K installed, maybe more. We've only had one multi-day outage in the 12 years we've lived here, because our wiring is all underground and it took a century level storm to wipe it out. We get occasional outages of a few minutes to a couple hours in the winter if a tree hits a power line somewhere in the nearby above-ground grid, but that's about it. I'd still love to be the only guy in the neighborhood all lit up when everyone else goes dark :). To be fair, I'd actually be #2 now, guy a few houses up the street is that beacon of light now. But still.
When we were shopping for houses out in the sticks, I had that generator budgeted right into the price of the house. If I got a multi-day outage very year, it's a no brainer.
zrail 9 days ago [-]
Yep, exactly. At our previous place we never had an outage last more than a couple hours, in 7 years, so it didn't make sense. Current place has had four in the span of four years, plus we have geothermal heat so we can't just hook the furnace to a portable genset.
It'll never pencil out in terms of dollars saved on lost food and hotels, but just knowing that the power will be out for a max of 15-20 seconds makes it worth it for us.
fires10 8 days ago [-]
Gas distribution systems are often shut off in my area during natural disasters. That's why I usually install a propane or diesel generator. They run off a tank.
Dennip 9 days ago [-]
There was a good video on B1M related to this recently
Sadly, the outages and possible the loss of life connected to it could have been prevented if the gas companies hadn't fought back against stricter weatherization rules[^0].
> they made recommendations to the Railroad Commission to implement weatherization rules on the natural gas supply chain because there had been water coming up from the formations — it's called produced water, it's naturally occurring — and it was freezing at the top of the wellheads and restricting gas flow both at the wellheads and in pipelines.
And yes, the Railroad Commission is not in charge of trains, but oil and gas in Texas.
[^0]: https://www.volts.wtf/p/whats-the-deal-with-the-texas-railro...
> When load is being shed involuntarily, customers designated as “critical load” can be exempted. Critical load is typically demand from entities, such as hospitals, for whom a power interruption could be extremely costly. To be deemed as critical, the customer must first file paperwork. The winter storm revealed that certain parts of the natural gas supply chain – such as natural gas compressor stations – were not designated as critical load. In consequence, their power was cut, thereby reducing flows of natural gas along the state’s pipeline network and contributing to partial and complete derates at multiple natural gas power generation units. The loss of their output in turn necessitated further load shedding, potentially creating an unstable feedback loop. This represented a single point of failure in the energy supply system.
https://www.bakerinstitute.org/sites/default/files/2022-02/i... (pages 13-17)
https://engineering.cmu.edu/news-events/news/2023/04/25-gas-... ("U.S. natural gas pipelines vulnerable to electric outages")
https://www.sciencedirect.com/science/article/pii/S104061902... | https://doi.org/10.1016/j.tej.2023.107251 ("How vulnerable are US natural gas pipelines to electric outages?")
Those should be the first requirements before being able to be deemed critical.
Heck, I’m familiar with some orgs that sell their backup generator capacity to be on-call to the grid in the event of supply shortage. To them it’s a profitable load test that reduces the risk of outage.
Strong agree; however, it would be highly unusual to find that any facility that knows to file critical load paperwork has neglected this, so I'm not sure that it would actually do much other than inconvenience the process.
I suppose gas distribution networks tend to be over-engineered for safety because if something goes wrong, it goes really wrong: https://en.wikipedia.org/wiki/Merrimack_Valley_gas_explosion...
It would be so great to regulate fixing that instead of getting rid of it entirely.
ie - we should responsibly use all the excess natural gas rather than flaring it?
https://en.wikipedia.org/wiki/Hinkley_groundwater_contaminat...
However, the article doesn't say what the "PIG" is (but talks at length about how the "PIG" is "launched" or "received"). Wikipedia says it's basically a passive device that gets inserted into the pipeline and pushed along by the pressure to clean or inspect the inside of the pipe.
In the drinking water industry the pig is a large foam block that is shoved in the pipe, and the weight of the fluid behind it drives it along. It is used to physically loosen the accumulated debris on the inside of the pipe. This debris concentrates behind the pig, and when the pig arrives at it's destination you remove the pig and allow the fluid (and debris) to discharge to waste for a period of time until the fluid runs clear.
Some advancements include "ice pigs" which is just crushed ice. The advantage of an ice pig is you can hook up to a fire hydrant and pump the ice in, no need to access the mainline pipe itself. An ice pig will also disintegrate on its own, no need to remove it, just allow it to flow out of a downstream hydrant, any ice left behind isn't a problem.
Nowadays, they also have "smart pigs" that have sensors to detect gouges, dents, pipe wall that is too thin, etc. as the pig moves through the pipe, so that repairs can be made before the pipeline is filled with gas.
I’m guessing those are usually “dumber” ones.
Inside the tank terminals I had to witness and certify the pigging after each parcel loaded, when one chemical was done and the line needed to be cleared and volumes accounted for before filling with a different chemical. Among many other more or less toxic things. Measurement training was not easy in the full-scale industrial environment but you can't really lead as well in the micro-scale activities without it.
https://en.wikipedia.org/wiki/Pigging
> Some early cleaning "pigs" were made from straw bales wrapped in barbed wire[4] while others used leather.[5] Both made a squealing noise while traveling through the pipe, sounding to some like a pig squealing,[6] which gave pigs their name.[7][8]
We have a natural gas line running through one of our agency properties, and it was recently repaired due to the pig's findings.
Basically the engineers running the pig mark sections of the pipe that need physical inspection. The crews come out, dig it up, and repair or replace a section depending on how bad it is. Or do nothing if the engineers see that it's nowhere near as bad as they thought.
Id imagine there's something similar in Houston, this stuff is legit fascinating.
Practically, that's fairly far from true for today's technology. Gas is so cheap that we're happy to waste a bunch of energy to make the plant cheaper.
Without those it would be just like a very very long garden watering hose that has a trickle of flow compared to a short one.
The differential pressure from one end of a gas pipeline to the other is not 1800 psi - it is more like 20 psi. You don't repeatedly recompress along the pipeline length - you compress once at the start, and decompress once at the end.
The reason to use high pressures is because for a given pipe diameter (and therefore cost), you get far more gas transported at high pressures than you do at low pressures.
> You don't repeatedly recompress along the pipeline length - you compress once at the start, and decompress once at the end.
There are often recompression stations in pipelines precisely because pressure drops across the length, and on land it's cheaper to have those along the length of the pipeline than one really big one like NS1 had.
Yes, you do. That is the primary purpose of transmission compressor stations. You may just lose a few psi per mile or something, but over the course of 100s of miles..
That's only true in a word with incomplete physics. Friction and drag exist, there's no sense pretending a process is imperfect because of them.
1) Getting natural gas plumbed to your generator is expensive.
2) If you're running this generator for an extended period of time, things have pretty much by definition gone to shit and aren't working as designed. You have a lot fewer dependencies to go fill a couple of jerrycans with gas at the nearest gas station (that has both gas and power to pump it [0]) than you have to restore piped natural gas service to your property.
[0] And if a gas station loses power, getting it hooked back up restores its utility to everyone, whereas restoring power or natural gas service to a home only restores its utility to the person living there. Prioritizing gas stations over private homes makes a lot of sense.
If your threat model involves civilization deteriorating to the point where natural gas stops working then sure, a generator with fuel storage on site probably makes more sense. I'd argue that gasoline is the worst of available options though. Diesel and propane are much more shelf stable and typically more reliable than small gasoline engines.
Storing fuel is dangerous in general, but I believe that liquefied gas is more dangerous. It is more tricky. For example you need to store it in a ventilated environment, to prevent gas buildup. If you turned wrong nut you'll may be not able to turn if back due to pressure.[1] It can be treated safely, but it much more tricky that with liquid fuel.
[1] https://www.youtube.com/watch?v=JzdnUZReoLM
Liquid Propane requires surface space to “gasify”, and more space the lower the temp. That’s (one reason) why propane “pigs” are horizontal cylinders.
Unfortunately, there aren’t many small horizontal tanks.
Down the line I figure I'll be building some sort of generator "shed", and perhaps look at using the generator exhaust to warm the tanks. A loop from the heating system would positively solve the problem, but that feels like way too big of a circular dependency.
https://www.sciencedirect.com/science/article/pii/S104061902...
Massive landslides and floods will wipe out your natural gas lines, your propane tanks, your wind and solar generators, your battery backups...
Gasoline is a terrible choice in any case, it goes bad quickly if you don't stabilize it. The only time I ever see gasoline being used it's with little portable generators. Even then, I see a lot of people starting to choose propane instead now.
Of course, once you run out of gasoline or propane, you are once again dependent on the infrastructure.
[1]: https://thehill.com/regulation/court-battles/4896585-texas-g...
The most significant laws Texas enacted after the freeze — HB 3 and 5, SB 1015 and 2627 - mainly establish new funding for gas-fired plant construction, cut funding for renewable construction, and allow energy companies to raise rates on customers more frequently.
Observers will note that gas fired plants had the most unplanned outages, while renewable sources had the fewest. In any case, what matters is that the $9/kWh costs are duly distributed to the customers and tax payers, to the benefit of energy traders.
A natural gas powered permanent standby generator is amazing for peace of mind but they're a significant investment.
4 LiFEPO4 batteries run our fridge for about 8 hours. two 30lb propane tanks would run it for about a week, and the 30 gallon gas tank just recharging the batteries to just power the fridge could probably go 2.5 weeks.
If something goes wrong with a generac, you likely need a service tech to come out. If my portable unit acts up I have a 2nd new one in a box just in case. They're so cheap you can basically afford to keep one fresh for each disaster.
A portable inverter AC unit (ideally a dual-hose unit) will pull ~1700w on the high setting. You can cool a solid 1000 sqft even in the Texas heat with something like this while also running your lamps/wifi/starlink/fridge/etc.
Combine with something like an EcoFlow battery, and you can actually shut it off completely while you sleep (and lock it up inside safely). Setting the AC to the low setting will reduce its consumption to ~400w intermittently which will easily run on a 2.5kWh battery all night. The other advantage of the EcoFlow is that you can temporarily run much larger loads than the generator is directly capable of. Really good for induction cooktops and getting your washing machine spin cycle up to speed.
I've had my 26kW generac for almost two years and it's done several multi-day outages without issue. I just have my mechanical contractor come out and do the annual maintenance on schedule, keep track of the weekly self-tests, and otherwise don't worry about it.
When we were shopping for houses out in the sticks, I had that generator budgeted right into the price of the house. If I got a multi-day outage very year, it's a no brainer.
It'll never pencil out in terms of dollars saved on lost food and hotels, but just knowing that the power will be out for a max of 15-20 seconds makes it worth it for us.
https://www.youtube.com/watch?v=1eKsaGqUfvI