When 1522 is the tonnes of co2 saved what is the year?
CREATE TABLE "results" (
  "year" text,
  "universities" real,
  "no_of_students_signed_up" real,
  "pct_electricity_reduction" text,
  "tonnes_of_co2_saved" real,
  "saved" text
);
SELECT "year" FROM "results" WHERE "tonnes_of_co2_saved"=1522;