I had this exact situation on a film I shot back in the spring. As a student film, we were lucky to even afford a 1.2K HMI...
In retrospect, the 1.2K HMI wasn't quite enough to simulate sunlight the way I wanted it to. We had a fresnel (a PAR would have been better), shining into a north-facing patio door, lighting a kitchen (going for a bright, high-key morning aesthetic.) We rigged up some C-stands and grip arms, some black cloth and tarps to create a tent over the HMI, blocking out as much ambient daylight as possible, trying to make the light from the HMI as directional as we could without added skylight.
At EI 160, and with sheer white drapes, I was getting about 5.6 from about 5 feet away from the patio door, and dropping down to 2.8 deeper into the kitchen.
Ideally, I would have liked something more powerful like a 2.4K PAR or higher, placing the light further away from the patio door to get the same exposure inside but a smaller disparity in dropoff throughout the kitchen. And of course, some large butterflies to block out sunlight would have been a lot less sketchy than our set up (take a peek at http://tinyurl.com/m4q52).