Help Wanted - Cannot Fully Reconcile Clue With Solution

[guitarboogie]

14 down clue reads
"Singular 15 struck out with energy for part of Africa"

Solution is "KENYA"

OK, can see that Kenya satisfies part of Africa but for the life of me I just don't get where 15 in particular and the rest of the clue relates to the solution.
Clarification would be greatly appreciated please.

guitarboogie

[hc4361]

Have you got the answer(s) to 15 down and/or 15 across?

[Baldric]

Is there a 15 down or across that might help?

[scooping]

So what's 15?

[emeritus]

What is the answer to 15 a and or d ?

[guitarboogie]

Thanks to all 4 of you - NOW the penny drops for me ! the '15' in the clue refers to 15 down and this had not occurred to me - and the solution to 15 down is 'yanks' So... singular would be 'yank' plus 'e' for energy rearranged as Kenya
On again thanks to all of you.
Kind regards,

Guitarboogie

[dannyk13]

what have you got for 15?

[hc4361]

It's a common trick in crosswords, using the answer of one clue to answer another.

[guitarboogie]

to hc4361
I must admit I HAD come across the convention of clues now and then referring to another clue in the same crossword - but it just didn't cross my mind that this particular clue was one of those cases ... and when the penny dropped I really felt quite foolish. I'll just have to put it down to experience and resolve to bear this case in mind in future. Once again, thanks to all for the help.
Guitarboogie

[dannyk13]

If 15 is yank then if you make an anagram of yank +e = Kenya