A WIDE-RANGING life cycle assessment (LCA) study into the possible impacts of fracking in the UK has found that by some measures the controversial process is better for the environment than renewable technologies.
The life-cycle analysis carried out by chemical engineers at The University of Manchester is the most detailed yet, looking at 11 possible impacts – including acidification, eutrophication and toxicity – rather than just global warming potential as in previous studies.
The team looked at the impacts of shale gas production from exploration through to decommissioning, including fracking and drilling, and compared it with electricity generation from coal, nuclear, wind and solar resources.
One standout finding is that offshore wind and solar PV deplete metals and minerals up to 244 times faster than shale gas. For marine toxicity, solar PV and coal are respectively 7.8 and 45 times worse than shale gas.
The team warns that – depending on industry’s practice – positive findings could be tipped the other way making shale gas worse than any of the options considered, including coal.
“The shale-gas industry should assess carefully the following key parameters to minimise the environmental impacts from shale gas: the amount of gas that can be recovered per well, the volume and composition of drilling fluid, disposal routes for drilling waste and fugitive emissions from drilling and completion of the well,” says study co-author Adisa Azapagic.
The study comes as the UK government pushes ahead with plans to boost shale gas development, auctioning onshore oil and gas exploration licenses in July for half the country. Its findings serve to warn UK authorities of the need for tight regulation and enforcement, the researchers tell tce.
Fracking has proved publicly divisive, following earthquakes caused by operators, and reports from the US that drinking water has been polluted by the process. The degree of uncertainty about the true impact of shale gas production won’t be apparent until commercial operations begin in the UK, the researchers say.
“LCA studies depend crucially on data,” says study co-author Laurence Stamford. “We currently don’t have primary data for shale gas extraction in the UK as commercial exploration hasn’t started yet. When – or if – exploration starts, it will be important to obtain typical UK-specific data, including emissions during drilling, extraction of shale gas and from closure of wells.”
This uncertainty extends to answering public concerns about whether fracking will contaminate drinking water.
“The issue of drinking water cannot be addressed by a tool such as LCA so additional research is needed,” says Azapagic. “This should include long-term monitoring of groundwater before and after shale gas exploration and better understanding of the possible composition of flowback water, in particular, the concentrations of heavy metals and naturally-occurring radioactive materials.
“Unfortunately, we can only obtain these data once exploration has started so that everything before that is a guess, albeit an educated guess. However, with stringent regulation, water contamination is avoidable.”