IREN is a pure-play sustainable Bitcoin mining company that owns at least 84% of land and grid-connected power facilities to provide it with the flexibility to host other data centers.IREN's valuation suggests investors are buying into IREN's hard assets (property, facilities, and cash) and are getting its Bitcoin mining business for free.Although we currently find IREN to be fairly valued, IREN provides more upside if investors are willing to undertake more risks.We find that IREN is investable below $2.90 under the assumption that IREN stops mining Bitcoin if unprofitable, minimize non-cash expenses, minimize cash burns, and minimize ownership dilution.IREN's total mining cost per BTC is 30% higher than MARA and RIOT while stock compensation is similar to RIOT's or about half of MARA.