How well does a heat pump work in a LEED or Passive House certified home? 

Really well as it happens, see a great example of a split system heatpump installation in the Edelweiss LEED Platinum V4 Home below:

The Edelweiss House has a radiant floor to keep our feet comfortable but we rely on a Mitsubishi Mr. Slim ductless mini-split air source heat pump to heat the air of the house. This gives us air that is heated on average three times more efficiently (and three times cheaper) than had we relied on electric resistance heat in the form of baseboard heaters or our radiant floor boiler. 

We also have an air-to-water hybrid electric heat pump hot water heater that borrows that efficiency and significantly cuts the energy required to meet our domestic hot water needs. 

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