This year's orders are twice as many more than last year's.
Tips
grammar
A 是 B 的两倍 = 'A is twice B' (A = 2B). But A 比 B 多两倍 means 'A is two times MORE than B' (A = 3B). The 比 pattern adds on top of the base, so native speakers sometimes argue over it in news writing.
mistakes
Don't say 二倍 in speech; native usage is 两倍. 二 only appears in read-out numbers like 2.5 倍 (二点五倍).