Spoiler: If you insulate your espresso machine's boiler, you will save between 7 and 30 bucks a month on your power bill.

Cafe Power Bills

In 2007, I moved with my brother to Pueblo, Colorado in order to open a coffee shop together. One of my main jobs was to reducing operating costs of doing business, and the electricity bill was a big one! Between the lights, ovens, coffee brewers, walk-in refrigerators, and espresso machine, the bill was over $1500 per month. Often times way over.

Measuring Espresso Power Baseline

One item that I identified as a major power-suck was the all-important espresso machine. I took the top off and clamped an amp meter around one leg of the heating element. The Astra Mega III volumetric espresso machine draws a solid 4200W of power when the element is on. I installed a little power-timer so that its number wheels count up when ever the coil is on, this way I could get a time-averaged value for how much power it actually uses. I let it sit for several weeks.

I actually got two different baselines: One for a period of time when we were switching the machine off every night for 12 hours at a time, and one when we just left it on night and day. Both practices are common with commercial espresso machines, depending on hours and staffing.

Insulating the Boiler

Once I had collected enough baseline data, it was time to insulate the boiler. You may be shocked to know that virtually no espresso machines are insulated in any way! When I asked a manufacturer, he just said, "It's so the cup warmer stays warm." The cup warmer being the flat spot on the top of the espresso machine, right above the boiler. (By this logic, you might call a missing front door your 'porch warmer.')

I found a supplier of 3/4 inch thick industrial high temperature felt in Illinois and ordered a yard. After hours one night, my wife and I popped the lid of the Astra and measured where all of the pipes, hoses, and wires protruded from the boiler. We went home and cut the felt to match, with some degree of difficulty. We then wrapped it and secured the felt with big zip ties. It now looked like this: