If he is acquitted he doesn't get large monetary compensation to my knowledge.
(quote)
Anyone found not guilty may apply to the judge to have his legal costs paid out of central funds; this is not automatic, but is usual if the court agrees that the charges should not have been brought. The amount payable is set out
by regulations depending on where the case was heard; since October 2012 it has been set at legal aid rates, which are unlikely to cover a full defence team. Somebody who did not have a lawyer can charge for the time he himself spent on the case, but this is assessed at a standard rate similar to minimum wage, even if he happens to be an expensive lawyer.
Defendant compensation after not guilty verdict