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I've recently moved from an old Brugnetti HX machine to a Profitec Pro 300, which is a small dual boiler with ring group. It's very fast to warm up (10 minutes) and I'm getting much better results than I did with the HX. Very well built and o expect to get many years from it.
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Sidenote, my breville barista pro (not high end) had a lovely 3 second startup for those spontaneous coffees
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Congrats on the new machine!
James Hoffmann was involved in the development of the Prima One and has a review on youtube.
https://www.youtube.com/watch?v=7RXmIGgoYTE
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Completely agree! The wifi plugs are awesome. S
If I'm away for the weekend I can just turn it off via the app and have it turn back on for monday morning. The schedule function makes it so easy and no having to fiddle for daylight savings etc - does it all for me.
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I have a Wemo connected to my VBM for this exact reason. It has worked out great for me. Especially when driving home and I know I want a coffee. I can turn on the machine before I head home and I know it is ready once I pull up to my garage.Originally posted by WhatEverBeansNecessary View PostHonestly just get a wifi smart plug.
Set it to turn on 30 mins to an hour before you normally get up. 30 minutes is plenty of time, but on the odd occasion you get up early it's still ready. Then you also have the app you can turn it on and off with in case you are out and think 'man, I would love a coffee when I get home'.
The other alternative is to leave it on all day - heating it up 4 times a day probably uses as much or more energy than just leaving it on. But I don't have evidence to back this up, just a hunch.
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Thanks for the heads up. I ordered one of these yesterday.Originally posted by sam678 View PostThe Prima Eagle One may also fit the bill with an 8 minute warm up time and energy efficient design.
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FWIW I also leave my machine on during the weekends from 5am to 12pm and weekdays its only on until 8am as I normally leave for work at about 7:15am. I also don't drink coffee in the evening as I am sensitive to caffeine and I can't sleep if I have coffee much after 1pm.
But even if I did drink coffee at night I wouldn't leave it on all day as I wouldn't feel comfortable having a pressurised appliance on unattended and not being within earshot (despite the risk of catastrophic failure being relatively low).
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OK, I just read the article about the "experiment".
He presents a couple of results then makes a conclusion which is not justified by the results presented. He also cocks up his units, there's no such thing as a watt per hour, he meant a watt hour per hour or, as the rest of us call it, a watt.
I cannot show you how he arrived at his unjustified conclusions because he doesn't show his working but his primary assumption seems to be that if he turned the machine on again after two hours it would use the same amount of power to heat as it did the first time. This is obviously wrong because it will have lost less than 240 watt hours in that time by his own figures. The longer the time between turning it off and on the lower the net loss rate.
The results do a pretty good job of confirming my calculations: his static loss is 120 watts so the energy required to heat the machine up and make a couple of lattes is the other 310 watt hours used in the first two hours which is 1090 kJ. Subtract the energy for the lattes and we are in the same ballpark.
FWIW I leave my machine on in the mornings primarily because I don't want to have to wait for it to warm up properly before my second coffee.
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Morning Lyrebird,
Indeed once the thing is hot the only appreciable loss through the system is heat to the environment surroundings.
I would however point you back to the article that has done the experiment on this very subject I linked earlier. They concluded it was cheaper energy consumption wise to leave the machine on if they were going to use the machine again within about 4 hours. This experiment was completed with an energy meter on the machine only, but they also mention the energy savings are very small.
https://www.wholelattelove.com/blogs...usage-and-cost
I understand the point you are making about losses through the system - however the empirical evidence suggests otherwise.
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Had to do this as a separate comment as the editing window closed.
The other way around is your stated energy loss of 133W. The 500 kJ to heat the water and make the steam is pretty close to 133 W x 1 hour, so leaving the machine on is the equivalent of restarting it from cold every hour (but it wouldn't be fully cold in that time).
BTW yes, I've ignored the fact that the system loss during warmup would be under the 133W stated as for part of the time the temperature difference is low but this works in my favour anyway.
I also left out the energy required to heat the structure of the boiler, that will be about 20% of the energy required to heat the water. This time it works in your favour.Last edited by Lyrebird; 2 June 2021, 11:24 PM.
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Once the thing is hot, the only thing that matters is the loss from the system which is defined above.
If the temperature difference across the system boundary is constantly high, the heat loss must be greater than if the temperature difference changes between that high value and some lower value, giving a lower average temperature difference.
Ohmic heating is 100% efficient so the energy input will equal the energy lost. It really is that simple.
The rest of your argument is irrelevant but even if it wern't it makes no sense.
Your 0.4 kWh is 1.44 MJ energy, part of which will heat the water whle the rest is lost through the system boundary.
Take a reasonably sized boiler (1.8 litres) and assume it has 1.2 litres of water and 0.6 litres steam at 120kPa (gauge). It takes about 500 kJ to heat the water and make the steam if you started at 20 degrees so the boundary loss in this scenario is about 900kJ per 15 minutes or 3.6 MJ per hour = 1kW.
This is a patently ridiculous figure.Last edited by Lyrebird; 2 June 2021, 10:22 PM.
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Morning Lyrebird,
Unfortunately you have only presented one side of the argument here.
Yes Q = U * A * ΔT will (poorly without empirical results) approximate the heat loss during steady state operation. But you have neglected the original point that there could be energy savings in heating the machine up and leaving on for a period of time vs heating up and letting cool several times a day.
Essentially the only significant use of power (if we ignore the small amount used from lights and electric dials/gauges/displays etc) is the heating element to the boiler/boilers.
I'll demonstrate with a simple example:
Let's assume the machine takes 15 minutes of the element at 100% power to warm up to steady state (this will vary machine to machine). But for a 1600W machine x 15 minutes = 0.4kWh of power used for start up.
Lets also say that for 5 seconds every minute the elements is on 100% power to keep the machine at the temperature set point - per hour the machine is on it will use 5/60 x 1600W = 0.133kWh
We will also ignore the energy expenditure of pulling a shot/steaming milk because this will be the same regardless of each scenario.
So therefore the energy expenditure of heating the machine + leaving on for one hour while we make coffee = 0.4 (initial heat up) + 0.133 (energy for leaving on for 1 hour) = 0.533 kWh
Energy expenditure for heating the machine + leaving on for 14 hours (6am - 8pm) = 0.4 (initial heat up) + 0.133x14 (energy or leaving on for 14 hour) = 2.267 kWh
Therefore you would need to turn the machine on and heat up 4.25 times to match the energy expenditure = 2.27/0.533 = 4.25
Given OP said he makes 4 - 10 coffees a day it is possible he would do that at more than 4 intervals in the day - ie more than 4 times he would heat/cool his machine and therefore may indeed be better off leaving the machine on.
As rustyfence points out below you would need to enter the details for the specific machine to make the assessment and the above is a simplification.
However the US based WholeLottaLatte does this exact experiment with a power meter on a profitec pro 700: https://www.wholelattelove.com/blogs...usage-and-cost
They come to the conclusion that if you will be using the machine within next 4 hours you are better off leaving the machine on than heating up/cooling down in terms of energy expenditure only. There is also other things to consider including does the machine wear faster while left on or heating/cooling cycling.
Both the maths and experimental results seem to back this up.
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While I understand that there will always be teething problems at the “Bleeding Edge” I don’t want a phone to have anything to do with my machinery.
Yes, I am a Luddite, but in my experience this does nothing but add an unnecessary level of potential failure.
The HB thread on the Eagle1 is littered with reports of problems associated with the App/firmware.
Some are design flaws, some are user flaws but still issues.
I understand that forum posts tend to be biased towards brickbats rather than bouquets as people have difficulties getting the best from their expensive new purchase but why complicate it by adding a third party participant(phone)?
I am interested in the OE-1 if/when it comes out but wary of the App/software aspect and may go the way of the Strietman to avoid it.
Sorry for the rant/thread drift.
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Amberale, the only thing you have to control with the app is if you want to turn the steam pressure down from 2.5bars.
Everything else is done on the machine.
(Don’t get me wrong, also not a fan of apps! But thankfully I almost never use it!)
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