How much of a role is Fracking playing in this supply of inexpensive natural gas?
I’d be concerned that we are trading one set of environmental pollution issues for different and potentially more serious one.
It’s cleaner in many ways.
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Natural gas produces less CO2 per unit of energy than coal (1 C per 4 H’s, as opposed to about 1 C per 1-2 H’s).
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Combined-cycle gas turbine plants (CC-GT) can hit net efficiencies of greater than 50% (some are close to 60%, and some claim to be 60% but I’m not sure). Coal plants typically have a net efficiency of 25-35%, with brand new ones being just above 40%.
The combination of 1) and 2) means that all things being equal, they produce much fewer GHG emissions than coal.
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Gas has little to no ash in it.
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Gas has little to no sulfur in it (no SO2, SO3, or H2SO4 emissions).
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Gas has little to no mercury and other heavy metals in it (but not none; look it up if you don’t believe me).
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Gas does produce some NOx, but this can be easily controlled via an SCR (just like coal), except on gas plants the SCRs are smaller and cheaper and work better.
So overall yes, gas plants pollute a heck of a lot less than coal. Even with BACT controls on the coal plant, there’s still no fair comparison.
Fracking is a major component of the new extraction technologies which have led to the boom in natural gas. It’s not the sole technology, but it’s the easiest and most effective one, IIRC. Here we sort of reach the end of my knowledge on that subject. I think it’s safe to say, however, that if fracking is outright banned, the cheap gas will go away for some time, until a new cost-effective method of equivalent effectiveness can be used.
However, IMO the pollution issues of fracking are both manageable and small, relative to the “business as usual case.” An example I can give is a gas company I’ve worked with, who has seen one case of a farm with contaminated groundwater as a result of their gas development. One, single, farm. Meanwhile, they’re producing enough gas to cleanly power about 500,000 to 1,000,000 homes. Is one farm which needs to run off city water worth relatively clean energy to a million people? Seems like a good choice to me. I’m sure there may be other situations where the choices are not so clear, but really, there’s been a bit of hysteria over fracking which is mostly the part of the “brain-dead” contingent of the environmental movement, but also partially the fault of the “brain-dead” contingent of the energy producers.
They have a huge problem around Greenbrier, AR with earthquakes.
There is much saying it [doesn’t get into wells,](arkansas water wells fracking) though.
I still can’t read the word “fracking” without suppressing a giggle.
When I hear the word ‘fracking’ I always think of machine like space aliens bent on killing the last remnant of humanity…and mashed mushies. Weird…
-XT
I’ve read about this, but I haven’t paid much attention. Is there any reason why this would affect coal more than nuke or gas? This is way out of my field (I try to not burn stuff), but I’m assuming that any process that is ultimately coupled to a steam turbine is going to need a similar cooling system, depending on what sort of heat sink is available. The only possible difference I can think of are plant size and age.
Yeah, I dismissed those out of hand once. I believe now I was too hasty and wrong to do so, although in my defense I had been ignorantly thinking of widespread quakes, rather than local ones. Doesn’t matter, however, if the quake is under your feet.
You pegged it on the last sentence. This rule has a potential to shut down many small (< 100MW) coal units, maybe ones up to 250MW if the circumstances are wrong, where no one wants to put any more investment into them.
Many of the really old coal plants are small, not very efficient, and only keep running because the cost of coal and O&M is so cheap. If you take a 2x100MW coal plant where they piss and moan over spending $50,000 on repairing their thaw shed or $20,000 to repair their leaky air heaters, and tell them “you need a new cooling water intake structure and heat dissipation pond system that’s going to cost $2M”, they’ll say “screw you guys, we’re going home” and scrap the plant. I guess on the plus side, this rule will make a forced clean-up of some of the dirtiest (per MW) coal plants.*
Simple-cycle GTs don’t need cooling towers or water, and combined cycle plants do, but don’t have the same water requirements as a coal plant of the same size. Nuke plants are big enough that the companies will eat any capital investment needed.
- But on a nostalgia point, I’m old enough now that I’m seeing quite a few plants I worked at being shut down or planned to be shut down, and a lot of people I know taking early retirement or looking for jobs. Some of these plants I spent weeks at, roaming around and exploring, learning, and working on cool things. Meeting nice people. I wish they would stay open somehow, foolish as that may be. I love the unmistakable scent of burning coal.
If there is so little to be concerned about, there should be no need to exempt the process from the Safe Drinking Water Act.
Widespread use of the process has only occurred in the past 20 years with most of the activity in the past decade or so. Hardly time to realize the full impact of contaminated groundwater migration and other contamination vectors. Technologies and processes that have the potential to contaminate the freshwater supply, be it one farm or one thousand, should be regulated more stringently not exempted.
Not ignoring you, but I don’t know enough about the specific issue(s) to comment further on groundwater contamination concerns.
Neither do I. I just fear this will be another case of [del]unexpected[/del] dismissed consequences. The need for an exemption tickles that part of my brain that makes me worry that maybe widespread use of the process is rushing along a little too quickly. Hoping I’m being overly circumspect.
Simple-cycle/combined cycle?
Simple-cycle turbines generate power only from the turbine itself. Combined-cycle plants use the hot exhaust from the gas turbine to recover heat into a small steam cycle (with steam turbine), thus increasing the plant cost and complexity, but also the fuel efficiency.
In an industry that has numerous regulators that overlap each other, an exemption from one particular regulation does not in any way mean it is not regulated.
Long live wind, water, and solar. But it’s not going to happen.
Long live geothermal. But it’s not going to happen.
Long live gas. And if there’s enough out there, it will.
Long live nuclear. Hope not. And it will never be economical when all the costs are considered.
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Long live nuclear. Hope not. And it will never be economical when all the costs are considered.
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Yeah, especially the costs of overcoming all of the decades of ridiculous fear mongering and over the top propaganda against nuclear. That’s certainly going to be tough to beat, even when it makes the most sense.
-XT
All of the costs don’t have to have a rational basis, but they are actually there.
That’s why I was agreeing with you (except for the ‘Hope not’ sentiment).
-XT
Actually, one advantage of natural gas is that it makes it easier to incorporate alternative energy into the grid. Wind is already in the same ballpark as coal for price per unit of energy; the problem is just that it’s not consistent. If the wind dies down, then something else has to start up quickly to pick up the slack, and that’s a lot easier for gas than for coal.