Last year Germany exported about 9% of its electricity. So the country could reduce their use of lignite (~ 24% of total energy produced) by at least this amount.

And I think the math is off there - if Germany cuts 24% of its energy production over a couple of years, energy may become more expensive, driving away the factories using extreme amounts of electricity[1]. It would not result in losing a lot of jobs, and may even force some industries to become much more efficient (thus generating an advantage over competitors).

[1] eg, Aurubis in Hamburg using 1 billion kw/h per year with less than 7000 employees to refine copper