The only really limiting figure on the PW150 when it comes to T/O power is engine oil temperature.
In non-icing conditions, takeoff power may be set as soon as oil temperature is above 0°C, which is generally not really a problem to achieve. As my very estimated colleague has written above, the 55°C for departure in or into icing conditions are a different animal and take ages to reach on occasion.
As the oil is mainly heated by the bearings and the RGB, the time it takes to reach that magical number is directly related to engine speed. So in order to speed things up a little bit, taxi with both propellers unfeathered. When standing, placing the power levers ever so slightly behind the DISC gate into the reverse area (minding a possibly slippery ground of course!) will give You a percent or two of compressor speed as well and save some time.
While the time saved by this is certainly noticeable, it still takes ages to get the last few degrees. Do remember this when selecting Your mixture du jour for deicing! Being pennywise and taking only the thinnest possible mixture can come back to bite You in the rear end when You spend all Your hold over time waiting for the oil to heat up and need to come back for a second treatment.