Due to the hot weather which effected the electrical supply the factory production progress. we would like to re-schedule the inspection to 08 July afternoon. Please confirm
"The supply of power to our factory has been affected by the exceptionally hot weather, resulting in a loss of production, and we would therefore [be grateful if we could/like to] re-schedule the inspection to the afternoon of 8 July. Please confirm whether this is [acceptable/convenient/permissible/possible]."
The choice of wording given in square brackets depends on the context.
I have assumed that the power supply isn't affected throughout summer but only on days when it is
exceptionally hot, and so have inserted 'exceptionally' before 'hot weather' to emphasise the unusualness of the circumstances.