I wanted to start a new thread about:

*Leaving an espresso machine permanently ON - Vs -
*Leaving it on most of the day during the times it get used and turning it off in the night only. -Vs -
*Always turning it off after use. So 4 times a day minimum, maybe upto 10 times a day when it is turned on when needed and then turned off!

Which option saves electricity?
Which option causes more wear on the machine?

My physics memory from school tells me that the loss of heat in radiation is the main usage of electricity when it is permanently left on.

When it is switched off after each use, the energy needed to heat it will be equivalent to the energy lost as cooling. Am I right?

Can someone point me to the right kind of maths to use here? I have been trying to use the energy meter average for my espresso machine, and so far, I have had confusing results, because the app (by Samsung SmartThings) that is meant to maintain the energy metering keeps crashing or keeps getting stuck, giving me incorrect readings.

Kind regards
Dee

According to the companies that I've asked about leaving their (commercial) machines on 24/7 vs turning it off & on I was always advised to leave the machine on to reduce wear & tear. I did that with the Speedster for several years but eventually decided that there was no point in having it running while I slept. I also sleep better knowing that it isn't on. I now have both of my machines on timers which turn them on at 6am & off at 6pm everyday. I use both alternatively throughout the day & personally think it would be crazy to be turning a large commercial machine off & on 4 to 10 times a day.

As far as electrical consumption I've seen no real change in my bills between 24/7 use & 12 hours on/12 off use. I'd strongly recommend insulating your boiler/s if you haven't done that yet. When I insulated the steam boiler in my old Vivaldi V2 I saw a 40% drop in heating cycles. Both of my current machines have the boilers insulated but I didn't record any before & after data.

You might consider buying a WeMo Insight programmable timer that will record all your machine's energy use and can export a spreadsheet detailing daily energy consumption in watts and dollars & cents.

Electric resistance heating, which is what an espresso machine is, is essentially 100% efficient, if you are living somewhere where you're in heating mode this time of year anyway, there's no real down side to leaving the machine on. It's only a slight negative if you're heating with a heat pump that has an energy efficiency rating above 100% (COP-1). In air-conditioning mode it is an energy efficiency negative, as the air-conditioning is working against sources that are creating heat.

Perhaps an espresso machine is somewhat akin to a tube amplifier that might exhibit fewer problems if left 'On' so that it maintains a stable operating temperature.

SomersetDee wrote:When it is switched off after each use, the energy needed to heat it will be equivalent to the energy lost as cooling. Am I right?

This question comes up regularly. The poll Do you leave your espresso machine on all the time? was posted back in 2006. Leaving a Prosumer HX Espresso Machine On CAN SAVE ENERGY was in 2010 and started with the claim that leaving the espresso machine on 24/7 saves energy (?!?). I decided to measure:

HB wrote:Rather than try to recall my college physics lessons, this evening I measured my Elektra Semiautomatica using the Kill-a-Watt. The cumulative kWh data from a cold start:

1 hour consumed 0.30 kWh
2 hours consumed 0.45 kWh
3 hours consumed 0.60 kWh

Based on the last hour of usage, it consumes around ~0.15 kWh per hour when fully heated, or 3.6 kWh per day (0.15 * 24). If you were so inclined to cycle it four times per day for two hours per cycle, allowing it to cool completely between each cycle, it would consume 1.8 kWh per day (0.45 *4). The additional energy cost of 24/7 operation in this case would be 1.8 kWh (around $0.20 in our area).

Of course, if the boiler has any insulation at all, it would be unlikely to cool down completely in the hours between on/off cycles, so the energy savings would be greater than an exposed boiler machine like the Semiautomatica.

On a related note, I know that Counter Culture Coffee used to leave their machines on all the time, but now use timers (La Marzocco has a built-in one). I'll ask their service manager if they've noticed any uptick in component failures as a result.

I'm running a Linea in a café and I chose to turn it off every night and back on in the morning. Energy consumption aside, I'm guessing there is then less wear on the p stat and heating elements.
The machine has been in service now for 4 months since the overhaul.

JohnB. wrote:According to the companies that I've asked about leaving their (commercial) machines on 24/7 vs turning it off & on I was always advised to leave the machine on to reduce wear & tear. I did that with the Speedster for several years but eventually decided that there was no point in having it running while I slept. I also sleep better knowing that it isn't on. I now have both of my machines on timers which turn them on at 6am & off at 6pm everyday. I use both alternatively throughout the day & personally think it would be crazy to be turning a large commercial machine off & on 4 to 10 times a day. As far as electrical consumption I've seen no real change in my bills between 24/7 use & 12 hours on/12 off use. I'd strongly recommend insulating your boiler/s if you haven't done that yet. When I insulated the steam boiler in my old Vivaldi V2 I saw a 40% drop in heating cycles. Both of my current machines have the boilers insulated but I didn't record any before & after data.

Hi Dan, John, Steve and Kyle:

Thanks!! Yes all good pointers. Yes, have read the other posts. Nothing appeared very conclusive and scientific. Either regarding wear or a conclusive report on current consumption on an insulated machine. I do not know if a lab-style experiment has ever been done in this regard. Also the maths involved is not clear (to me). A lot of bias and personal opinions cloud this topic. This topic is especially hot in Europe where machine made in EU are being forced to have insulation as an EU directive.

I have attached mine to a heavy duty relay that measures KWh. This also helps me switch it on or off remotely. Shamefully the SmartThings hub keeps getting stuck and has proven to be very unreliable. It is very good for the money but it gets "stuck" once every day rendering KWh readings useless.

So I do not have long duration measurements. My machine (Strada 2gr) consumes 4800+ Watts during the heating up cycle. I have one group switched off. So it consumes 4512 Watts during the heating up cycle. During the steady cycle it consumes 16w with bursts of 250w. I think it may average about 0.15KiloWattHour. This average is what I keep messing up when I try to measure. I use an Aeon relay, But the relay is not at fault. It is the SmartThings-software implementation, or the Samsung SmartThings hardware, or both, that is at fault.


From what I read: It can be confirmed that the *insulation* is the key to understanding this. I got confused because the KWh readings for a machine that ran for 20 hours continuously was not very different from another day when I tried turning it on and off about 6 times in 24 hours. Both readings came to about 3.8 and 3.6KWh respectively. Giving me a reading that showed a *lower* power consumption when the machine is turned on and off. Only then did it hit me that the current drawn cannot really alter much because the current drawn is only proportional to the radiative loss regardless of how many times it is powered on. Even when it is on all the time. It is effectively being switched on and off by the internal PID. So a coffee machine is perpetually in an on off cycle. So the question becomes one of insulation and radiative loss despite insulation.

(here I am theorising)
The claimed advantages of reducing metal stress by leaving it on can only possibly apply when the boiler completely lacks insulation and is prone to cooling down completely when powered off. ? Or is there something about heating coils, and scale formation that I don't understand? Such an uninsulated machine also will be power hungry because of radiative loss. So catch-22.

I would also imagine that the insulation my saturate and may also radiate eventually when it is On long enough? My Physics is shaky at best here.

My Strada appears to have been insulated at factory, and I am not sure if additional insulation is good or bad for the machine. There is enough room to put one more layer of that shiny material. The more I can reduce the radiative loss the happier I am about switching it off every now and then. Especially if I go to bed early and expect the household to wake up late. Timers don't work well on SmartThings.

As far as wear, the boiler never really goes cold in mine. After 1 hour of being powered down, the boiler is still in the 80s (almost 90C) in winter with the kitchen at ambient 17C and with the machine near a window. After 12 hours of non use, the boiler is still around 34 deg C.

I used to leave it on, but the cooker being on the same line means I do not have them both on at the same time. That was the original reason I needed to frequently power it off. This is also when I noticed that Strada only takes 13 minutes to get to 126C from 34C and less than 3 minutes to get from 95c to 126c. It appears to climb about 8 deg C every 60 seconds drawing 4570W!! Now I am of the opinion that as long as I don't let it cool too much (30 c) then it is probably better to turn it off in the night and some of the time in the day. I still feel unsure. lol

kindest regards
Dee

I still feel unsure.

This is my 2¢ Professional opinion and what I would likely do in you situation.

As someone that has for decades repaired and modified professionally, High-end tube amplifiers and High-end High-power Class-A transistor power amplifiers, for reasons related to reliability, I would leave the espresso machine 'On' 24/7, except when going on vacation.

As a professional that now designs geothermal heating & cooling systems, I would again suggest leaving it 'On' 24/7, except during vacations, as you mentioned that during the winter your kitchen is 17°C.

It doesn't much matter whether the boilers are well insulated or not - there is essentially only one place for all that heat energy to ultimately go - into the envelope of your home. Electrical heating energy is still more efficient than even the most efficient gas boiler or gas furnace (in terms of energy efficiency, not necessarily in terms of energy cost).

Since you're heating anyway, think in heating terms and Btu, not so much kWhr.

I hope that helps...

IMPO

SomersetDee wrote:Yes, have read the other posts. Nothing appeared very conclusive and scientific. Either regarding wear or a conclusive report on current consumption on an insulated machine.

Well, if you give equal value to every post on the internet, you aren't going to be able to reach a conclusion!

In terms of energy consumption, the facts are well known and established; more energy is used if a device is permanently powered than if it is intermittently powered. You can easily demonstrate that for yourself with a cheap killawatt energy meter. Just manually log energy use over a few days using either scenario.

FWIW, I measured the energy consumption of my Iberital L'Adri 1 group some time ago. Left on for 24 hours a day it averaged
4.5kWh a day. On from 07:00 to 22:00 it averaged 3 kWh a day, which is the sort of result that you would expect. For most people running big espresso machines, I doubt that the running cost is much of a consideration, so the sensible answer is to just do what you want. If leaving the machine on makes you feel good, leave it on. If you don't mind waiting for it to warm up, leave it off unless you are using it. If you're bothered about the environment, get rid of it and buy an efficient machine (those pod machines are quite good!) I've chosen to use my machine on a timer so it's on from 7 a.m. to 20 p.m.; no delays when I want a coffee, but no energy wasted when no one is going to want to use the machine.

You won't find data on reliability; it's very difficult to assess and I doubt that anybody's bothered enough to try and measure it. However, thinking about the make up of espresso machines you realise that they are generally robust, heavy duty machines. They aren't delicate little flowers that are liable to break at every application of power. Also, think about what you do when you switch the machine on: the main thing is that you apply power to the heating element. But that heating element is being cycled continuously while the machine is powered up in order to maintain a stable temperature, an extra on/off cycle or 2 isn't going to have a huge impact.

(Comparing a valve amplifier to a coffee machine is completely fatuous. Valves are delicate devices operating at temperatures much higher than coffee machines - the only similarity is that they both get warm.)

SomersetDee wrote:This topic is especially hot in Europe where machine made in EU are being forced to have insulation as an EU directive.

I don't think the EU rules mandate insulation, but they are imposing energy saving measures on domestic coffee machines, along with all other domestic electrical appliances. This is a good thing and it's about time machine makers started designing machines with low energy consumption in mind.

Thermal expansion and contraction is a consideration for the heating coils' longevity, in my view.

I don't favor heating up the boiler coils then cooling them down multiple times throughout the day, every day, thus I use a timer that provides constant power to the machine 12 hours daily then it is off 12 hours.

My espresso machine is here to give espresso whenever I or a family member want it. It wasn't an inexpensive decision to make that happen.

Spending $5 a month in electricity, or whatever it costs, is part of the ongoing price for that delicious delicacy as is the price of buying beans, roasting them and grinding them.

Not saying what anyone else should or should not do with their machine. It's their call and their money.

Charlene wrote:Thermal expansion and contraction is a consideration for the heating coils' longevity, in my view.

Good thing that the coils are in litres of water, then!