harrisonpatm wrote:Alright then, a query, in theory only. Without going into the specifics and doing the math for specific heat calculations. What do you think of reducing the boiler size for a 1-2l "prosumer" machine, rather than the 6l boiler being discussed? For someone only making 2-3 shots a day? Sorry, theres an idea in my head now and it won't leave until it gets some answers?

That is an idea i considered when i bought my actual machine, that would be actually the most effective way to reduce the power consumption. You would get a very similar consumption to a home use espresso machine.
Although this option is the most effective, it is also by far the most expensive, and the risks involved of ruining your machine are not low either. On top of that, if you decide in the future to sell your machine, you are going to have real trouble...

I decided that it was not worth the hassle, but that depends on each person.

now the specifics:
La Marzocco Linea Mini warm up test with real time power draw
somehow not many people measure the warm up energy / power consumption...
from the video in that link, you can see that the power meter shows 3 cents previously to turning on the machine and 9 cents at the end of the video. As he is in the US, bay assuming $0,3/Kwh the power consumption we would be talking about is 0,2Kwh

which is quite impressive considering that it has a 3 liter boiler, my old gaggia used from cold start to the morning coffee 0,1 Kwh with a 0,1 Litre boiler.....

This topic is quite interesting to me. "Boiler volume" has several implications, and people might be more or less sensitive to heat up time, energy cost, environment-friendliness, or simply pleasure for minimalistic yet effective engineering.

I think Robot (and similar machines) with its boiler-less approach deserves a special mention. The fastest workflow, and on-demand heating of just the amount of water is actually needed appears hard to beat. My measurements indicate about 0.001 kWh of energy per double shot. Personally the ability to have coffee on demand without prehating the machine were at the root of my choice when I bought the Robot.

quamau wrote:I think Robot (and similar machines) with its boiler-less approach deserves a special mention. The fastest workflow, and on-demand heating of just the amount of water is actually needed appears hard to beat. My measurements indicate about 0.001 kWh of energy per double shot. Personally the ability to have coffee on demand without prehating the machine were at the root of my choice when I bought the Robot.

I think you wrote one zero too much there as the energy needed to warm the 60ml of water for an usual double shot from 20°C (68°F) to 100°C (212°F) is 0,00556 Kwh.

does anybody know how to change the name of the topic? i would like to add something like Energy or power consumption to the title to attract more posters with useful information about power consumption

Jeff wrote:The average US electricity cost is around $0.13/kWh, so it may not be as low as you estimated. It is still pretty good though.

Reading on in that thread, people are reporting 12-15 min until the boiler is hot. 1/4 hour * 1 kW or 1/5 hour * 1.25 kW draw would be 0.25 kWh.

Ref: https://www.electricchoice.com/electric ... -by-state/

During winter time, themachine heat the house (a little bit)

Yep, apologies, one zero too much: my number is measured as the power consumption of a microwave (700W) for 60-65 seconds, plastic container with minimal thermal mass. I may have misused the word "double" as I pour two cups with 18gin-36gout combined. And I did not mention that I start from hot water, that is free for me energy-wise, at about 50-60°C. The measurement obviously includes the (in)efficiency of the appliance and a few secs of useless boiling time.

Regardless, with 0.01kWh bottom line is always that the energy cost is basically zero, and power occupation on the low side.

Snoroqc wrote:During winter time, themachine heat the house (a little bit)

mine does not only heat up the home a little bit

I wonder what kind of energy usage could you expect after cleaning the machine of limescale...

I may have increased the boiler size after all...

Snoroqc wrote: Regardless, with 0.01kWh bottom line is always that the energy cost is basically zero, and power occupation on the low side.

yeah that is true, even more if you compare it with my energy usage....

After a long limescale removal I finally got the first preliminary results:

I am planning to operate the machine one week with the boiler insulated and the original capacity then i will reduce the water volume.
I have found out that just by using a longer water probe I can reduce the content of water in the boiler up to 1.5 liters while keeping the highest point of the heating element around 1 cm below the water surface.

The only information that I can provide right now is that the warm idle consumption has reduced from 360W to 140W

I wonder how much power does a e61 machine consume in warm idle. I could at the most expect it to be slightly lower, but it would really surprise me to be any lower than 100W, since I have insulated even the siphon pipes and most home machines do only insulate the circumference of the boiler.

Hello again,

I got the final results. At the end I did not use any glass marbles or any creative solution. As I took apart the boiler for the first time, I noticed that there was some dead space below the heating element. On top of that, the heating element was not "pointing downwards" so the amount of water that I could reduce by elongating the water probe was not much.

After checking the technical documents, I noticed that the heating element was not correctly installed, the heating element should be pointing down. After installing the heating element properly I measured again, the minimum amount of water that would cover the whole heating element. 1.5L did cover about half a centimeter the highest point of the element.

At the end I adjusted the boiler to fill up to 1.6 - 1.7 L to be in the safe side.

The results are an average measurement of at least four coffees under the same conditions. I did a row of measurements as the machine was still not insulated, then the machine insulated and finally insulated and with the volume reduction. I have also plots if anybody shows interest but i need some help to post them, I have no idea how to do that.

------------------------------------------ Original ---------------- Insulated --------------------- Insulated + Water probe
First coffee of the day ----------- 0,61 kWh ------------- 0,59 kWh --------------------- 0,4 kWh
noon coffee ------------------------ 0,54 kWh -------------- 0,37 kWh -------------------- 0,32 kWh
Total -------------------------------- 1,15 kWh -------------- 0,96 kWh --------------------- 0,72 kWh

I am pretty happy about the results, although for my use case insulating the boiler might have not been the most cost efficient measure....