Energy policy

Study: “plumes” of methane released into the atmosphere by a few super-emitting shale gas wells

  • 22 Apr 2014, 13:30
  • Robin Webster

Methane emissions from some shale gas wells could be up to a thousand times higher than official estimates - meaning they have a warming effect orders of magnitude higher than previously thought. But the finding only refers to a few 'super-emitter' sites, a tiny proportion of the total number of drilling locations, accordong to a recent study. 

The government argues that the UK could burn gas  instead of coal as a way of cutting greenhouse gas emissions from the energy system. That includes domestically produced shale gas

But some academics argue that gas leaks during the process of extracting shale gas from rock - known as fracking - could make the fuel far more climate-polluting than its supporters claim. 

The evidence is contested, and other researchers disagree. But a new  study from researchers at a number of American universities appears to support the idea that 'fugitive' or unplanned emissions from shale gas wells could be substantial. The study identifies a small number of sites where drilling for shale gas has released large amounts of methane into the atmosphere. 

 

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Degrees of change: the IPCC’s projections for future temperature rise

  • 15 Apr 2014, 12:00
  • Robin Webster

Many governments are trying to reduce greenhouse gas emissions. But unless policymakers raise their ambition significantly, temperatures are likely to rise beyond safe levels. We examine the pathways that could take us towards a two degrees temperature rise by the end of the century - or considerably higher. 

On Sunday, the Intergovernmental Panel on Climate Change (IPCC) released the last in a series of three reports, which together assess the physical evidence that climate change is happening, the  expected impacts over the course of this century and what would need to happen to curb the rise in greenhouse gases.

Embedded in the reports are the scientists' predictions for how high temperatures are likely to rise this century - and what that's likely to mean for ecosystems and societies around the world. 

Comparing scenarios 

The IPCC bases its projections for future temperature rise on two different techniques. 

First, the IPCC has created its own storylines, or scenarios, describing how high temperatures are likely to rise in the future and what that might mean. The scenarios vary according to different predictions for how societies develop and how much effort we make to reduce greenhouse gas emissions over the course of this century.

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Excitement over ‘clean’ underground coal gasification masks technical reality

  • 15 Apr 2014, 10:50
  • Mat Hope

Coal is cheap, abundant, and responsible for about 40 per cent of the world's electricity generation. That's a problem, because it also has some of the highest greenhouse gas emissions of any energy source. It's no wonder that a technology that could allow the world to continue burning coal - but cleanly - is being met with some excitement, then.

Writing in the  Telegraph at the end of last year, Algy Cluff, chief executive of energy company Cluff Natural Resources, said 'underground coal gasification' could "provide a vital energy solution and produce abundant and cheap gas for generations". The technology briefly put its head above the parapet again today, as the  BBC asked whether it be "the clean energy of the future".

The prospect has certainly piqued the government's interest, with energy minister Michael Fallon  establishing a working group to explore its feasibility.

But is it too good to be true? We explore underground coal gasification's prospects and try to separate the theory from the reality.

What is underground coal gasification?

Underground coal gasification (UCG) involves drilling down into coal - normally deep underground - then igniting it. The resulting gas then runs up another borehole and is collected on the surface, as the diagram below shows:

 

underground coal gasification diagram

Once the gas is collected, companies can use it to run power stations, or convert it into transport fuel. Carbon capture and storage (CCS) technology can be added, reducing the process' emissions, and making it relatively 'clean'.

As such, the government now sees the "exciting potential" of UCG as means to generate abundant, domestically-sourced, ostensibly fairly low carbon power in the UK, the Telegraph  reported.

So, what are UCG's prospects in the UK?

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