SIR – Unfortunately, Mr Goldsbrough (T&A, April 8) is being rather optimistic in thinking that there is plenty of oil left and that we will find more.

The current global daily use is just short of 90 million barrels, so we need over a billion barrels every two weeks.

This puts into perspective the Brazilian and Falklands finds of around ten billion barrels, which are still ten years away from reaching the surface.

They won’t help much, and neither will the Canadian tar sands, distilling oil from sludge, as they are expensive and polluting.

Moreover, it now seems from the Wikileaks papers that the Saudi reserves have been overestimated and increasing home demand there and in Indonesia means there is less available for export.

The supply problem can only worsen with car sales rocketing in China and India, so oil is going to be expensive while it lasts.

Keith Thomson, Heights Lane, Bradford