Tom.
I have one idea for you. If your heating oil cost is on the 4th place, you might think of your house insulation improvement.

By the way, one hint from me. The electric bill in California is quite noticeable. I've managed to save about 20% every month after installation of motion sensors with timers in place of regular light switches for non critical indoor lights. After a month of use my family even found such an innovation quite convenient to have