My Variation on the same theme

use strict;
use Data::Dumper;

my %hours;
@hours{0..23} = (0) x 24;
my @siteList = qw {site1 site2 site3 site4};

my %struc;
map {$struc{$_} = {%hours},} @siteList;

print Dumper(%struc);
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