user: Question: When 1522 is the tonnes of co2 saved what is the year?
Columns: ['Year', 'Universities', 'No. of Students Signed up', '% electricity reduction', 'Tonnes of CO2 Saved', '£ Saved']
Types: ['text', 'real', 'real', 'text', 'real', 'text']
Sample row: ['2006-07', 1.0, 130.0, '10%', 90.0, '£19,000']
SQL:

assistant: SELECT "Year" FROM "Table" WHERE "Tonnes of CO2 Saved" = 1522.0;