If your goal is to save energy, you can do this by starting your dried pasta in cold water. Alton Brown has a cold water pasta method that works great. By starting in cold water, and using less water, this method will be quicker and use less energy.
64 ounces cold water
1 box dry pasta ((farfalle, rigatoni, penne, etc.))
Cooking pasta (i assume dried pasta here) has two stages:
The hydration can be done completely off the stove, earning you back come of the cooking time and energy. Just soak the pasta in water, it depends on the type of pasta and thickness, if your soaking time is more than 4 hours, i would refrigerate it to avoid food-...
I sometimes do something similar, and I've found that you have to rely on trial and error and testing. Different shapes have different thicknesses and this seems to affect cooking a little differently at lower temperatures. Of course you'd use a lid and a lower than normal quantity of water. Don't stir, as this means taking the lid off, but swirl the pan ...