There's a limited list of zero-rated items and bitcoin is not on it. Bitcoins are however, VAT exempt as argued here, under the "payment services" exception https://bitcointalk.org/index.php?topic=259045.0 .
The unfortunate consequence is that "suppliers of Exempt goods cannot reclaim the input VAT (the VAT on their own purchases) relating to Exempt Supplies" -> so that would mean no VAT recovery on ASIC equipment.