Learn to dig Coal.
The United Kingdom holds 77 million tons (MMst) of proven coal reserves as of 2016, ranking 61st in the world and accounting for about 0% of the world’s total coal reserves of 1,139,471 million tons (MMst).
The United Kingdom has proven reserves equivalent to 1.9 times its annual consumption. This means it has about 2 years of Coal left (at current consumption levels and excluding unproven reserves).
https://www.worldometers.info/coal/uk-coal/
Learn to find coal.