Xeon Server Under 100W

I'm doing some math here for a colocation project. We need each 1U server to consum less than 100W (220V) or else no more than 0,5A

I was looking for Dell PowerEdge R410, it offers several processor options.

Both these have 60W TDP:

Intel® Xeon® L5520, 2.26Ghz, 8M Cache, 5.86 GT/s QPI, Turbo, HT, 1066MHz Max Mem
Intel® Xeon® L5506, 2.13Ghz, 4M Cache, 4.86 GT/s QPI, 800MHz Max Mem

And both these have 80W TDP:

Intel® Xeon® E5504, 2.0Ghz, 4M Cache, 800MHz Max Mem
Intel® Xeon® E5502, 1.86Ghz, 4M Cache, 800MHz Max Mem

I'm thinking of having 4x 1TB HDD's and a 3ware raid controller.

Do you think it's possible to stay under 100W with this configuration, using the L55xx processors?

Are these L55xx worthy? Or it's a waste of money?