A Perspective on Fracking by Prof. Dave Reay
I like gas. Each morning it is the source of instant heat for making my coffee. Each winter’s evening it is the roar in the boiler that spreads warmth through the house. At work too, this energy-packed gas is a daily focus of our climate change research, but it’s there that its darker side often comes to the fore. Natural gas consists almost entirely of ‘methane’ and, as methane is a greenhouse gas 25 times more powerful than carbon dioxide, it presents both problems and opportunities in the fight to limit anthropogenic climate change.
With a fossil-fuel heavy global energy system, methane looked like a 20th century success story in terms of tackling climate change. In the UK, the ‘Dash for Gas’ helped to nudge out carbon-intensive coal-burning power stations for more efficient, lower-emitting gas-fired versions. Per unit of electricity produced, gas power stations were emitting less than half the carbon dioxide of their coal-powered predecessors.
Since those heady days of North Sea exploitation that poured oil, gas and money into the UK, getting enough methane to keep the powerstations, cookers and boilers going has become increasingly difficult. National and global demand for gas has rocketed and easily-exploited supplies have dwindled. Imports of gas from Russia have risen, and with them the volatility of price and supply.
Now, the global expansion of a new extraction technology called ‘fracking’ heralds a new ‘Dash for Gas’ that could serve to provide energy security and carbon emission cuts which dwarf those of the last gas boom. Unfortunately, this new process, and the vast reserves of gas it makes available, pose a major threat to avoiding dangerous climate change.
Fracking is a process whereby water, chemicals and sand are injected at high pressure into methane-bearing rock and shale deposits. The high pressure water opens up fissures in the rock and the sand particles (called proppants) then keep them open to allow the methane to flow. Once’ fracked’ the methane in the rocks can then be drawn out and used. The process is already used widely in the US, with huge extractions from the methane-rich Marcellus shale in the east of the country underway.
The huge volumes of ‘fracked’ methane have allowed the US to radically reduce its domestic use of coal and to close in on full energy security. So far, so good. However, coal production in the US has continued unabated, with the bargain-price coal now being shipped overseas (much of it to Europe) and burnt for energy generation there. In effect, methane fracking in the US has meant a reduction in US carbon dioxide emissions, but an increase globally. Add to that the great uncertainty over the amount of methane that is leaked from fracking sites and this new ‘Dash for Gas’ begins to look like a major problem for climate change mitigation.
To our atmosphere, exactly where greenhouse gases come from does not matter, it is the amount emitted globally that counts. ‘Dangerous’ climate change is commonly cited as being a post-industrial increase in the global average temperature of 2oC. We have already seen warming of 0.75oC and, on our current course, we are likely to well exceed the 2oC level during this century. Global expansion of methane fracking helps to lock us into this high emissions trajectory. It means a new generation of gas-fired power plants that will go on emitting CO2 for decades to come, while renewable generation struggles to compete with the low-cost, short-term gas bonanza.
For the jobs and growth agenda of most governments though, methane fracking is inevitably seen as a boon. In the UK it could help buffer energy prices and create new income streams as North Sea wells run dry. Globally it can help power economic development and temporarily bridge gaps between supply and demand. Methane fracking exemplifies the kind of tradeoffs that have to be made between energy security and climate security, but there is little evidence that such tradeoffs have been properly assessed by the governments backing the fracking boom.
They like gas and so do I, but methane is a fossil fuel. As such our reliance on it has to wane rather than wax in the face of accelerating anthropogenic climate change. It is time that policies on fracking and similarly Janus-faced pillars of ‘sustainable growth’ began to encompass the time-span of human lives instead of parliaments.
Prof. Dave Reay is Chair in Carbon Management & Education at the University of Edinburgh’s School of Geosciences. Dave is Assistant Principal Environment & Society and the Director of the Global Environment and Society Academy, he is the designer and editor of the climate change science website Greenhouse Gas Online and of the Southern Ocean: Antarctic Seas and Wildlife website and has authored a number of books on climate change, including children’s book, ‘ Your Planet Needs You! A Kid’s Guide to Going Green’. For more information about Dave and his work visit the GESA website