Banner

Friday 20 March 2015

What the frack are they doing?

I hear a bit about fracking, mostly on the news or in the types of magazines, blogs and websites that I visit, and most of it is negative.  When I hear a bit about something, but don't know enough to be able to form an informed opinion, it's time to do a bit of research.

So what is fracking?
Technically it's called Hydraulic Fracturing.
Image result for fracking uk
image from www.theguardian.com
Under the ground, there are layers of different stuff.  Quite a lot of it is rock (think back to school geography lessons, igneous, sedimentary and metamorphic), but mixed in with those, particularly the sedimentary types, you'll find organic material.  Forests and other plant material that has got buried within the sediment and over millions of years has been squashed and heated to form coal, oil and natural gas.   It turns out that this stuff is quite good to burn and gives off a lot of energy, so we've been digging it up and burning it for the last couple of hundred years or so.  Unfortunately, there are two problems with that: 1) we're running out of the stuff and it's now more difficult to get, and 2) it turns out that burning all this stuff is gradually raising the temperature of the earth, and it's now got to a pretty bad state.

So, back underground.  The easy oil and gas has been found and exploited, or is in volatile countries who we have to keep sweet so that we can have our fix of the bad stuff.  But hey presto!  They've found out that there's a supply of natural gas right here in our own back yard!  It's not that easy to get out of course.  With conventional oil and gas drilling you just drill a hole, and because it's under pressure, it comes spurting up for you to collect.  This stuff is hidden away in tiny pores in shale rock.  To get it, you have to inject water down into the rocks, which makes a fracture and you can force the gas out.  You also have to inject sand, to keep the fracture open.  And also a little bit of biocide, surfactant, lubricant and stabiliser, though I couldn't quite work out what they were all for.  Anyway, that's what fracking is.  You can only get gas out from the small area around the fracture, so you usually drill a few wells from a single point.
Image result for fracking uk
image from bbc.co.uk
Why the controversy - that sounds okay?

  1. Okay, so firstly there's the groups who say we shouldn't be investing in more fossil fuel extraction when climate change is such a problem and we should be trying to wean ourselves off the stuff and use renewable energy sources.  The argument to this is that while gas is still a fossil fuel, it's a much cleaner fossil fuel than coal.  Using gas instead of coal in electricity generation emits half the CO2, and almost none of the Sulphur Dioxide or ash.  Also, since we are still very dependent on fossil fuels, doesn't it make sense to exploit our very own domestic source, which doesn't need to be liquified and shipped across the world, and isn't at the whim of hmmm... volatile neighbours.
  2. Water consumption and water pollution.  Two different beasts here.  Fracking uses a lot of water, more than conventional oil or gas drilling.  Natural gas electricity generation, however, uses less water than either coal fired or nuclear power generation.  The concern about water pollution is that this chemical cocktail that's being forced into the rocks is coming back out (about 10-40%, though  much is recovered for future fracking activity).  The actual chemical make-up of the cocktail is a closely guarded secret, so nobody is quite sure what's in it.  Do we really want this puddling about and potentially entering our water supply?
  3. Air quality.  The drill process does mean that there's a bit of extra organic material floating about in the air in the vicinity of the well.  But natural gas electricity generation emits a lot less air pollution than coal fired, so there's possibly a net gain there.
  4. Earthquakes - really?  Yes, the anti-frackers say that all this high pressure water injection is creating earthquakes right here in Britain.  Apparently though, this was in the early, unregulated world of fracking.  Now, while fracking does cause tremors, these are not generally felt by Jo Public.  The argument is that conventional mining activities have a much greater potential to cause geological problems (as evidenced by sinkholes appearing in heavily mined places like Stoke-on-Trent).
  5. Visual appearance and construction - it's true.  Wellheads aren't attractive, and the initial fracturing and well construction takes about 2 months and quite a bit of HGV movement.  However, the wellheads are generally on low ground and therefore much less visually intrusive than a wind turbine, and wind turbines involve more traffic in construction too.
So, that's why people don't like fracking, and the arguments to refute those concerns.  I confess, it doesn't sound as bad as the anti-frackers had me believe.  On balance though, while this all sounds very reassuring and "not as bad as coal", that doesn't go far enough for me.  Just because you're "not as bad" as something else, it doesn't mean that you're good.  I still think that the investment should be in reducing our energy requirements, and finding better, more efficient and less intrusive renewable energy sources, not just finding a "not as bad" halfway house.
image from independent.co.uk
What do you think about Fracking?  Is there a controversial issue that you want to know more about?  Let me know by commenting below.

No comments:

Post a Comment