Keith: sorry this took a while.

1000W Bona Vita electric kettle, with 1L water at about 250ft above sea level took 6 minutes to boil and shut off. I used it to make an americano and then an espresso with the mypressi twist, with about 15 minutes between two two double shots (took 1 minute to bring the heater water to a boil after that 15 minutes). This included pre-heating the twist two times between each shot, and I'd turn the kettle on to bring the water to a boil (it shuts off at boil).

Total was 0.12 kilowatt hours.

1000W Rival kettle took 4 minutes to boil about 12oz water at 250ft above sea level. It was used to make a cup of black tea.

Total was .07 kilowatt hours.

Hope that helps you.

I picked up a case of 600 gas chargers for my twist, cost comes to about $0.0854 per shot, in case you are interested.

Before we can trust the reading of a Kill-A-Watt during the idle time, we need to know the sampling rate.

Here's a simple method of estimating energy draw for an espresso machine. Turn the machine on and let it come up to temperature, say, one hour. Then, measure how much time the heater light is on for a given period, say, 5 minutes. Multiply that ratio by your heater's kW and that's how much it uses while idling.

I did this for my Isomac Millenium before and after adding 1/4" ceramic felt insulation and found the insulating the boiler reduced energy consumption by 45%.