If you don't need the lighting there all the time, try using a Goldenrod
tube heater - I use them to raise temperature and lower humidity in several
closets and enclosed spaces. Available from 12 watts on upwards. Very
reliable, do not burn out, and none of their energy goes into lighting, if
that is not needed in the pump house. Many retailers, mostly marine supply
places, but here is garden shop offering one:
http://www.onestopgardens.com/osg/ta...emnumber=41100