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Comment by abejfehr | Hacker News Reader

I don't think natural gas is actually a carbon-neutral alternative to coal, my understanding is that methane leakage makes it almost as bad as coal in the long term.

https://www.vox.com/energy-and-environment/2019/5/30/1864381...

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A LOT of methane is released during coal mining as well, it's estimated that 9% of total global methane emissions can be attributed to it:

https://www.epa.gov/cmop/frequent-questions#q6

True, but it doesn't have the incredibly horrific non-carbon pollution problems of coal. The things almost every coal plant in the world does to nearby rivers would nauseate most people. Fly ash produced by coal plants releases one hundred times the radiation into the environment as a nuclear plant of the same capacity.

That’s only true because the amount of radiation released by a nuclear plant in normal operation is also negligible.

The actual number closer to 1,000 than 100. There is a lot of uranium and thorium in coal. Not all of it is captured when coal is burned.

https://www.scientificamerican.com/article/coal-ash-is-more-...

"A lot" is relative. From what I can tell, coal ash contains about the same amount of uranium and thorium as granite and slightly more than ordinary soil. (Of course, it's less concentrated in the coal itself, which is largely carbon and hydrocarbons that gets burnt off.) The main reason coal power releases so much radiation compared to nuclear because there's a lot of coal burnt and normal operation of nuclear power plants also releases very little.

What's more scary is the production of things like rare earth minerals - that quite heavily concentrates the uranium and thorium as part of the extraction process, producing large quantities of relatively radioactive mining waste.

Natural gas is way cleaner than coal overall. It does not release particles that kill people over the long term either. It's a pretty clear cut between the two.

If you only compare the burning stage.

Coal leaks methane too. A while ago there were people here pointing that even more than natural gas; I'm not convinced, but both are on the same ballpark.

Anyway, methane is a short term problem. It's CO2 that is long term.

It isn't neutral at all, it's merely less-intensive.

Leakage is a problem with straightforward extant solutions, but well operators are poorly incentivized to implement those solutions—the loss is often too small to substantially impact their profit, and the leak is invisible (natural gas being colorless) so it's easy to turn a blind eye and not implement effective monitoring.

I'm not sure how we would implement any more effective monitoring of natural gas leakage. We have gas detectors all over the facility and personnel walk around with gas detectors on their coveralls. Flowmeters are generally not accurate to <1%.

I would expect the only credible thing we can do is design it out, e.g. by running seal vents to flare rather than safe location, improving reliability, flareless operation etc.

I imagine the majority of "leakage" must be unburnt hydrocarbon in flare and GT exhausts.

But when you say "straightforward extant solutions" what are you referring to? In the industry, nobody particularly assesses "leakage" or really designs for minimising leakage per se.

It could be mandated that all facility pressures be below atmospheric pressure. Then all leaks would lead to air getting into the pipes rather than gas getting out.

Clearly with that being the case, one needs much bigger more expensive pipes.

Had my lungs ruined by natural gas leaks. This solution sounds very scary.

That would easily solve the problem, by making any gas processing facilities completely uneconomic to operate ;)

I am quite interested in the idea of methane leakage though. There seems to be a growing consensus online that it exists and is significant, but within industry it is really not recognised.

> In the industry, nobody particularly assesses "leakage" or really designs for minimising leakage per se.

An interesting perspective.

You sound as if you have relevant first-hand experience. From your knowledge, what is the state of aerial/satellite detection? Those are the solutions that I've seen cross my news feeds in recent years.

I work for an operating company rather than a design contractor, and I'm involved in topsides. I can't quite imagine what benefit aerial/satellite detection would have. Before we start up a process system, the last stage of commissioning is to pressurise with a nitrogen-helium mix and get a contractor to go round with a very sensitive helium detector to catch any tiny leaks.

To put it in perspective, we have another low-tech approach where you put tape around a potential leak point, spray a soapy mixture, then count the bubbles. The pass/fail criterion is measured in bubbles per minute. Yet inside the pipe you measure the flowrate in tens or hundreds of tonnes of gas per hour.

Possibly unburnt hydrocarbon in the flare could contribute to this "leakage" but flares are designed for complete combustion so I can't imagine it would make any difference in terms of GHG emissions compared to the already-considerable CO2.

We already have plenty of fixed gas detectors and personal gas monitors around site that are sensitive to about 0.04% methane (I think) so I can't really picture a satellite doing anything better.

Also, as you can probably tell from my comment already, I know very little about satellite surveillance for methane leakage, only that it is not common practice for operating companies.

I'd like to interrogate those ideas, if you don't mind? I'm truly curious here. Somewhat skeptical from the impression my reading has given me, but I don't mean to be hostile.

The initial testing is all very well, and I have no reason to expect it's at all ineffective, but I imagine it would be more interesting to look at the consequences of wear/weathering over time.

I suppose my biggest question is the mechanism by which those (fixed and personal) detectors work. I know that the aerial solutions work via lidar, and I expect satellite similarly looks for absorption in particular wavelengths.

https://spectrum.ieee.org/tech-talk/at-work/test-and-measure...

I recently saw an intriguing software engineer job posting for a company in Montreal & Ottawa that deploys satellites for testing/surveying for methane leakage. I was tempted.

I didn’t say it was carbon neutral.

Coal adds much more CO2 to the atmosphere. At least twice as much?

Rather than losing more time waiting for the perfect solution, a big step 10 years earlier might buy us additional time.

Don't you mean the short term? Methane being a very potent greenhouse gas but it breaks down with time.

Methane breaks down much faster than carbon and methane leaks can be mitigated. You don’t have to have them.

It breaks down into carbdon dioxide.

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