Senator BOB BROWN (Tasmania—Leader of the Australian Greens) (14:27): Mr President, I ask a further supplementary question. Honourable senators interjecting— The PRESIDENT: Order! I have to listen to Senator Brown's questions. Order, on both sides. Senator Brown you should ignore the interjections that on both sides of the chamber are disorderly. Senator BOB BROWN: Mr President, it is not difficult to ignore both sides. Honourable senators interjecting— Senator BOB BROWN: The Cameron government, in pursuing a 10 per cent reduction in greenhouse gas emissions across its properties, achieved a 13.8 per cent reduction last year and is now aiming for a 25 per cent reduction by 2015. Mr President, I ask: beyond the 10 per cent, will the parliament and you consider emulating the Cameron government's aim of a 25 per cent reduction in power consumption by 2015 in this parliamentary building?