Across
1 sugar snap SUGARS NAP
6 sept/Septs double def
9 collision course COLL(ege) IS <1> ON COURSE
10 site ET (film) IS (rev)
11 alchemic CLAIM HE (anag) + C(arbon)
14 beer money BEER + M<ONE>Y
15 sedan S<ED>AN
16 onset ON before SET
18 biodiesel B<I>ODIES + EL (Chicago rapid transport system)
20 perjurer J(udge) after ER in PURER
21 flan FLAN(k)
25 subsistence wage WAGE after BUSINESS ETC (anag)
26 Sodom SO<DO>M(e)
27 absurdity BUT DIARY’S (anag)
Down
1 sacks/Sacks double def
2 galette GA<LET>TE
3 rain (i)RA(I)N
4 naif I<A>N (rev) + F(ellow)
5 penalty box PENALTY (fine) + BOX (evergreen plant)
6 stochastic CHAS T(renet) in STOIC
7 pyramid DI<MARY>P (rev)
8 Suez Canal SUE Z(one) CA(circa) N(orth)A(frican) L(ocation)
12 amateurism AS IMMATURE (anag)
13 in absentia I NAB SENT I A(dmit)
14 blogposts POST after LOG in BS (bullshit)
17 strobed ST(reet)/ROBED
19 syllabi I<BALLY>S (rev)
22 needy Y<DE>EN (rev)
23 onus (b)ONUS
24 jeer J(ok/E(centricity))ER