Solar powered attic fan ideas

[kenbo90]

Greetings all,
I bought a solar powered attic fan that I would like to also run via ultility power. The motor is rated for 36volts DC/13amps(stated on label). The panel is only a 30watt, so I figure 18v at approx 2-3 amps. What are some ideas for attaching to ultility. I have access to a13v/13amp power supply which I get a large pot for or can I just hook up a large rheostat directly to a 15amp outlet?

[I_Daniel]

Somehow something does not calculate true (gell). A solar powered motor but the solar cell does not appear to be able to drive it ? 36 Volt multiplied by 13 Amps is 468 Watt while the solar panel is only 30 Watt ?
If the motor is 36 Volt then the 13 Volt DC power supply will barely rotate it since this is about a third of the required voltage.

I must assume that the rheostat is on the 13 Volt DC power supply and all it does is either lower or higher the output voltage depending on the Amperes drawn by the device.
Of course if this "Power Supply" is actually a battery charger then the maximum DC-Voltage is usually round about 18 Volt and the rheostat is used for fast or slow charging.
A 24 volt transformer with a bridge rectifier and a 47000Mfd-64 volt capacitor (yes a whopping big capacitor with ouch for the price) would give you 33 Volt. But you will have to pay quite a bit for the transformer as it must be rated at at least 15-20 Amps. 20 Amp preferable to minimize overheating.