Hi,
ASUS Power Adapters are normally 'universal' (or worldwide) and accept the voltages normally found worldwide, so you just need to find a way to plug your adapter into the power outlet which should be different from U.S. outlets.
Check the input voltage on the label under your adapter which should be in the range of 100V to 240V AC and check the AC voltage in the UK to confirm it falls in this range.
U.S. power outlets normally only provide 120V AC, so if that's the only voltage your AC adapter accepted, you would have problems using it worldwide which may often use voltages in the range of 230V AC.
Actually, since the ASUS 180W charger is composed of 2 parts, the 'brick'/adapter and the cord, the same or similar 'brick' for the 180W adapter should be used in the UK, but it just may have a different cord to plug into the wall.
So, really you should be able to use your 'brick' in the UK, but you just need to find a way to plug it into the AC power outlet in the UK which can be done by getting a different power cord or using some converter for the U.S. power cord plug only, so that you can plug your U.S. adapter into the wall.
Hope this makes sense, but feel free to discuss or get more opinions.
