https://www.bbc.co.uk/news/science-environment-49395658

Saw this and it dovetailed nicely with what I'm reading at the moment.

Excerpt:

"Previous projections of the potential amount of shale gas under the UK may have been significantly overestimated, according to a new study.

Instead of 50 years of gas at the current rate of consumption, this new research suggests there are just 5-7 years' supply.

But the UK's fracking industry, which represents companies like Cuadrilla, dismissed the report. "

Leaving aside the fact that companies like Cuadrilla rely hugely on investment capital, and have a vested interest in painting the rosiest possible picture to bring in such investment, and that the figure of 51 years, cited in 2013 somehow means that 51-6=50. Let's assume that in fact the higher figure is correct. 50 years, at current rates of consumption.

That assumes that demand will stay at current levels. ie, we will have zero economic growth for the next 50 years, and that shale gas will not have to play an increasing role as supplies of conventional fossil fuels decline.

Historically, UK's growth rate has been around 0.6% for the last half century or so.

https://tradingeconomics.com/united-kingdom/gdp-growth

Mapping that onto the 50 year figure year by year, I found that this shrinks the 50 years to 39.5

The UK gets almost all of its gas from the North Sea. Production peaked in 2000 and was falling at around 3% per year

https://en.wikipedia.org/wiki/Peak_gas#United_Kingdom

Add the need to ramp up production to replace the decline in Natural Gas from the North Sea, and the 50 year figure declines to 22.5 years.

Then what?

In a way, I'm in favour of fracking now. If we do it now, we can afford safeguards. Public opposition means the fracking companies have to be on something like their best behaviour. When the energy supply really starts to tank, nobody will be inclined to care about what happens to the polar bears.