Constructive things to do with a fracking drill rig no 106.

Oo-er, it's a well head.

Oo-er, it’s a well head.


So Ed (Davey, that is) has spoken, and all is now OK with fracking. There are those, like Ed’s deputy, Michael Fallon, who have always thought that pulling as much gas out of difficult rock formations as possible is a great idea, but Ed’s speech to the Royal Society last week was, I think, designed to reassure those who worry about fracking and could do with a little soothing. However, I’m not sure that it has had the intended effect. Most of the soothing we already know – that fracking done properly probably won’t compromise water sources; that it probably will not cause dangerous earthquakes; that we need gas in the energy system for some years to come and so on.

We also know (or should) that there will be plenty of gas around to fulfil our system’s needs over the next twenty years without drilling holes all over the country. And that drilling and producing from the huge number of wells across the country that would make up the sort of production levels that Ed now clearly envisages might be a problem in its own right. The debate, I would have thought, ought not to be about whether some wells are drilled to test for resource, which is what the above wider issue is being smuggled in under cover of, but should be in terms of that wider issue itself. Which Ed is clearly signalling at by suggesting that some of the proceeds of this widespread drilling that we don’t really talk about could be placed into a ‘sovereign wealth fund’. A fund that will only become significant if all those pads across the country actually do appear with the wells on them.

I guess, however, that we may well all quieten down at the prospect of a few wells being relatively safely drilled for exploratory purposes. And then we’ll have to watch as they turn, incrementally, into the rash of plants necessary for the realisation of the investment in exploration. We might regret being so quiet about it then.

In the meantime, here is another thought about what you might do to produce the sort of energy you might reasonably expect to get, one way or another, by drilling those fracking holes. I’ve ruminated on the comparative economics of producing far more climate friendly gas from an extensive roll-out of anaerobic digestion plants. You could perhaps go a bit further than that, and use almost exactly the same drill plants to produce another low-carbon equivalent, and drill for geothermal energy. Interestingly, geothermal drilling does involve almost the same processes up to a point – you drill a deep hole, you find a resource, and water gushes up. Except, on this occasion, you don’t need to inject a huge amount of water and chemicals, and then collect it and dispose of it as hazardous waste. Because the water IS the resource, coming up as hot water at about 74 degrees Celsius. When you’ve taken the heat out of it, you just put it in the sea.

I know a little about this since Southampton, from where I’m writing this piece, has had a geothermal well producing heat (and cooling) for most of the major public and commercial buildings for well over thirty years; energy we might otherwise have been getting from gas-fired boilers in individual boiler rooms over the same period. It arises from a single well head, romantically sited in the car park of the local Toys R Us store. Yes, it’s that threatening. And by the way, geothermal wells do deplete (eventually) by about a degree or so in temperature over a hundred years. So you don’t need to redrill every eight years.

Unfortunately, our friendly neighbourhood well in Southampton is currently the only geothermal heat producing well in the country, but things are stirring. It has been estimated that the geothermal resource (like shale gas, not available uniformly across the country) could supply the equivalent of almost ten gigawatts of installed electricity capacity, or 100 gw of heat per year. The Government’s modest support programme for resource proving in 2010, together with the Renewable Heat Incentive may well get some further projects under way soon. For instance, there is such a project currently underway in Manchester, being promoted by GT Energy, the leading UK geothermal development company. But this is a pinprick compared with what could and should be done. Technically, and economically, there is no reason why perhaps 15% of the UK’s 2030 Renewables Target cannot be provided by geothermal.

Two problems though. Firstly, will all the drill rigs needed to establish viable geothermal plants have been commandeered by gas-hungry frackers over the next few years? Secondly, even if they are not, might some members of the public not mistake a drill rig hard at work on getting hot water out of the ground not think it’s a fracking well and blockade it? It would be nice to think that neither problem will arise and large numbers of places, like Southampton, will be geothermally warmed in years to come. Doesn’t quite look like it right now though.



Not very big news – three FSADs equal one FGW. (It’s about fracking, by the way).


Also while we’re on the subject of Shale gas and today’s hoo-ha, it’s probably worth disinterring and updating the piece I produced on shale gas and biogas some time ago (here).

What I said in that piece was that it might be worth comparing and contrasting what you might get out of a farm size anaerobic digester by way of useable biogas (with just a little bit of cleaning up you can inject biogas into the grid, use it to produce electricity or as a fuel for vehicles) and what you might get out of the lifetime of a drilled and fracked gas well (same provisions, same use).

The two methods of producing gas can be summarised thus:

Biogas                                                                                                   Fracked gas

Costs about  £2 million to build a farm plant Costs £6-10 million to drill a well
Needs lots of cow poo etc. Needs 6 million gallons of water to frack
Lasts as long as cows keep on producing Lasts about seven years
Emits about 11g CO2 per kwh of electricity produced Emits about 400g per kwh of  electricity produced
Doesn’t look that great at the end of your road Doesn’t look that great at the end of your road
Can be used to store hay if you don’t produce Needs to be capped and made safe when exhausted
Good for energy security Good for energy security


Well I was a bit wrong in my estimates on the relationship between farm sized AD plants (FSAD) and fracked gas wells (FGW).  My original projection was that the output over 20 years of four FSADs would equal the output of one FGW.  Not a bad comparison – about the same overall price range and much cleaner gas. However, looking at some of the detailed literature on the results of fracked well lives over a period from the US (e.g.  Arthur Berman 2009) I was a bit out. Berman suggests that the average life of horizontal wells is far less than initially suggested by promoters – in fact about 7.5 years, during which time an average well in Barnett shale will produce  about 0.81 billion cubic feet, which translates as about 22.6 million cubic metres of gas.

A farm AD plant, on the other hand will produce about 6.2 million cubic metres of gas over a 20 year period.  True, you can drill another well after 7.5 year if we want to make strictly fair comparisons, but that does double your cost.

So, here’s the metric:   three farm sized AD plants at the bottom of three lanes give you slightly under the likely production of one fracked well at the end of one lane.  I’m not sure the residents of the respective lanes would really take to either, but at least with the AD plants they would be able to rest in the knowledge that they would be contributing to low carbon energy, rather than participating in forcing a lot more high carbon energy out of the ground.  Oh, and some of the farmers and their families down the lane might keep the income from the digesters  instead of having to be sweetened up to allow someone else to walk off with it.

Of course, though, there won’t be any development and production allowances to assist with the development of farm AD, because, well, it’s just not strategic or exciting is it?  So I guess the cows will go on doing what they do and the frackers what they do. Shame really.