[dundun]

They have a widget on the Nest store (https://widgets.nest.com/en/calculator/widget) that estimates energy savings. According to that, a $250/year savings is possible in SF with electric heating and a house over 2000 square feet. Though, the range they provide probably means:

a) It is a historically cold year for a prolonged period of time

b) You set your heat to 80F all the time

With gas heating, it looks almost impossible to save $250... unless you're heating an NBA arena.