Electricity Consumption Questions

[Peter009]

Hello again

 

I am on the final stages of setting up with the marine electrician, the power on our boat.

 

We have 12V and 240 going through a Victron inverter but am looking at options in terms of computers and monitors due to the nature of my work needing that sort of equipment.  I know I can get 12 volt monitors and adaptors for 12v for laptops etc but am wondering whether anybody out there is actually using a mains PC not a laptop using some sort of adaptor for 12V and am not even sure if that is possible.  I am not that worried about it as when not on shore power we would not be using the main PC which is mains power but if there is an option to set up a PC to 12 volt I would be really interested to know about it.  In the future we would like to get a generator and solar but don't have the money for it yet.

 

Our intention is to set that area up with normal sockets as well as 12v usb connections in the wall and maybe 12v cigarette charger sockets for other equipment should we need it.  

 

Also before I get the normal you should do your research replies, I have been looking into it and that is why I am asking the question here as I am not sure there is an easy option or an option at all and may be wrong so hoping someone will know more than me.

 

thanks

 

 

 

 

[BilgePump]

The power supply unit in a desktop PC puts out voltages of 3.3v, 5v and 12v iirc so the actual circuit boards and drives don't demand 240V AC.

A USB socket supplies 5v DC, the ones I've used at 1A or 2A. Sockets that convert 12v DC to 5v dc USB supply are really handy in a boat/caravan etc.

My little GRP boat has no electrics but I carry an 85Ah leisure battery, a fused 12v cigarette socket with crocodile clips and a fused USB socket with clips. I just clip one or the other on when I need to charge my phone, handheld VHF batteries etc.

[Tony Brooks]

If a good laptop ill not suit then I expect you need a very powerful desktop that probably needs a lot of power. I think I would run it from the Victron and adjust the power/charging calcs to allow for this.

[Alan de Enfield]

4 hours ago, Peter009 said:

Our intention is to set that area up with normal sockets as well as 12v usb connections in the wall

I would just check out your requirements as all the USB sockets I have seen /used are only 5v (not 12v)

[mrsmelly]

I run all my stuff 24/7 from the mains/combi. Dont mess about with 12 volt. My desk top, telly, fridges etc etc etc etc are all standard household mains stuff.

[Detling]

5 hours ago, Peter009 said:

 

 

anybody out there is actually using a mains PC not a laptop using some sort of adaptor for 12V

 

 

 

It's called an inverter and converts 12 volts to 240 volts AC, you already have it.  You can get a thing called a pico psu  to run a normalish motherboard from 12 volts but it is low power, so no massive gaming rig graphics cards, and overclocked top end processors. it is put in place of the existing psu and you would need to open the computer to fit it, the computer then would not run from 240V mains.

 

You also need to remember that the boats DC supply although nominally 12 volts will vary from about 12 up to 14.5 volts and maybe even 15 volts occasionally, it also has lots of voltage spikes often over 100 volts but very short, caused when pumps are switched off. I would never feed an expensive device direct from a boats supply I would always use a buffer and smoothing filter/device for protection.  Even cheap and cheerful basic LED lights can die in use.

[Jen-in-Wellies]

The headline power figures on computer stuff is useless. A PC might have an 800W power supply, but that only says it can supply 800W running some extreme application that draws that at its peak. Say video rendering in a high end game. Other headline energy usage figures will be marketing ones designed to make it look better than it is. The only way to go is real world measurement under your usage conditions.

Stick an energy monitor on your existing mains computing items and see what they use in practice doing the sort of things you need to do. You need total kWHr's used for each item after a typical days work. This can be easily converted in to AHrs from the battery.

Not knowing what your work is, I don't know what sort of energy they will take out of the batteries. The computing side of things will take power depending on how hard the cpu is working. Very hard for something like video processing. Not at all hard for simple web development. A faster computer will do the processor quicker, but use similar amounts of energy in doing it and have similar drain on the batteries. The only advantage of a newer computer is that the chips are smaller and use less power as time goes on, excepting the very latest, which can be a bit leaky. Real world measurements under your normal work conditions are the only thing to be sure.

Similarly monitors. Real world measurement. The big current drain with monitors are the backlight, so smaller is better, running it dimmer and a newer monitor with LED backlight will be better. If you need a huge monitor and true colour representation for work, then that has an energy cost to your batteries. 12V vs mains is a red herring. The energy usage is similar. Mains gives you more choice, but gives losses in the inverter. Your Victron will give low losses compared with some makes. 12V gear will need conditioning to protect computing gear from spikes on the supply from things like pumps on the boat and this will also come at a cost in losses.

 

Jen

Edited April 6, 2019 by Jen-in-Wellies

[Chewbacka]

Above is very true, one thing to consider, is if the inverter is running most/all of the time, say for powering your fridge, then you may as well run everything from your inverter and not have lots of 12v converters.

[MtB]

37 minutes ago, Jen-in-Wellies said:

The headline power figures on computer stuff is useless. A PC might have an 800W power supply, but that only says it can supply 800W running some extreme application that draws that at its peak. Say video rendering in a high end game. Other headline energy usage figures will be marketing ones designed to make it look better than it is. The only way to go is real world measurement under your usage conditions.

Stick an energy monitor on your existing mains computing items and see what they use in practice doing the sort of things you need to do. You need total kWHr's used for each item after a typical days work. This can be easily converted in to AHrs from the battery.

Not knowing what your work is, I don't know what sort of energy they will take out of the batteries. The computing side of things will take power depending on how hard the cpu is working. Very hard for something like video processing. Not at all hard for simple web development. A faster computer will do the processor quicker, but use similar amounts of energy in doing it and have similar drain on the batteries. The only advantage of a newer computer is that the chips are smaller and use less power as time goes on, excepting the very latest, which can be a bit leaky. Real world measurements under your normal work conditions are the only thing to be sure.

Similarly monitors. Real world measurement. The big current drain with monitors are the backlight, so smaller is better, running it dimmer and a newer monitor with LED backlight will be better. If you need a huge monitor and true colour representation for work, then that has an energy cost to your batteries. 12V vs mains is a red herring. The energy usage is similar. Mains gives you more choice, but gives losses in the inverter. Your Victron will give low losses compared with some makes. 12V gear will need conditioning to protect computing gear from spikes on the supply from things like pumps on the boat and this will also come at a cost in losses.

 

Jen

 

 

I'd say all this is spot on. Although I read the OP several times and couldn't quite work out what the question is. 

 

Computers use remarkably large amounts of energy because they tend to be used for long periods. Replacing that energy when off grid needs carefully planning for.

[Boater Sam]

Could you run one of these off the engine and save all that voltage conversion ?

 

[Paul C]

You can buy a laptop with an i9-9900K if you needed to. I don't see the need to go for desktop, when a laptop has the advantage of built-in display and keyboard etc being much more compact, and there's enough of a variety now that the high power workstations can do a decent job.

[OldGoat]

7 hours ago, Peter009 said:

Hello again

 

I am on the final stages of setting up with the marine electrician, the power on our boat.

 

We have 12V and 240 going through a Victron inverter but am looking at options in terms of computers and monitors due to the nature of my work needing that sort of equipment.  I know I can get 12 volt monitors and adaptors for 12v for laptops etc but am wondering whether anybody out there is actually using a mains PC not a laptop using some sort of adaptor for 12V and am not even sure if that is possible.  I am not that worried about it as when not on shore power we would not be using the main PC which is mains power but if there is an option to set up a PC to 12 volt I would be really interested to know about it.  In the future we would like to get a generator and solar but don't have the money for it yet.

 

Our intention is to set that area up with normal sockets as well as 12v usb connections in the wall and maybe 12v cigarette charger sockets for other equipment should we need it.  

 

Also before I get the normal you should do your research replies, I have been looking into it and that is why I am asking the question here as I am not sure there is an easy option or an option at all and may be wrong so hoping someone will know more than me.

 

thanks

 

 

 

 

The simple and quick answer - in reverse order to the above is / are

 

Definitely have normal mains 13A sockets "everywhere". I intended to do mobile IBM mini training onboard  and have loads of twin switched sockets. Even though the project never materialised, they're very useful for plugging in the vacuum cleaner up and down the boat. The same applies to 5amp 3pin switch-sockets wired for 12/24v (bad practice- but it's my boat...)

 

Provided that you have a sensibly sized inverter (is it an inverter / charger? or do you have a separate charger?) - 2400W would be nice AND  adequate battery capacity - say 1,000 A/h   then there's no reason why you can't run a high power PC all day long (what do you mean by high power PC - lots of graphics and a super monitor??)

 

If you're making your living from computer work then it's stupid to compromise your ability to work on the move - if you need to....  You may find / wish to do more work on the cut in the future if you realise that it is practical so to do. BUT (grammar) you MUST get the sizing of resources - batteries, inverter, cabling etc, right in the first place

Edited April 6, 2019 by OldGoat
Poor reviewing

[Alan de Enfield]

22 minutes ago, OldGoat said:

Provided that you have a sensibly sized inverter (is it an inverter / charger? or do you have a separate charger?) - 2400W would be nice AND  adequate battery capacity - say 1,000 A/h all day

Are you suggesting a daily consumption of 1000A/h ?

 

If so the preferred battery bank would be around 3,000 A/h (that's pretty big)

[Jen-in-Wellies]

6 minutes ago, Alan de Enfield said:

Are you suggesting a daily consumption of 1000A/h ?

 

If so the preferred battery bank would be around 3,000 A/h (that's pretty big)

A suitable battery bank! No computers though.

https://en.wikipedia.org/wiki/Milk_float#/media/File:Dairy_Crest_milk_float_(modified).jpg

[OldGoat]

 

8 minutes ago, Alan de Enfield said:

Are you suggesting a daily consumption of 1000A/h ?

 

If so the preferred battery bank would be around 3,000 A/h (that's pretty big)

Solly - reviewing problems...

If 'one' is going to do quality business work - and IME when the customer calls you have to act quickly, then getting you environment right, from the start is 'paramount'

[Alan de Enfield]

8 minutes ago, OldGoat said:

 

Solly - reviewing problems...

If 'one' is going to do quality business work - and IME when the customer calls you have to act quickly, then getting you environment right, from the start is 'paramount'

No worries.

 

If @Peter009 does become a 'large user' then the major problem is not going to be the size of the battery bank, but replacing the power used (+10% or more). How will that happen ?

 

Plugged into a land-line = not moving ?

Running the boat engine 8-12 hours per day ?

Running a portable generator = not moving ?

Running a built-in generator 8-12 hours per day ?

 

Or simply running a generator when using mains power ?

 

I have 6x 230Ah batteries which does allow us to be either large users, or stay put for a few days.

It does mean tho' that we have to do a couple or three days of 12 hours + cruising to recharge them.

Edited April 6, 2019 by Alan de Enfield

[MtB]

22 minutes ago, Alan de Enfield said:

Are you suggesting a daily consumption of 1000A/h ?

 

If so the preferred battery bank would be around 3,000 A/h (that's pretty big)

 

 

Could you or Old Goat explain what an a/h is, for the benefit of any newbies struggling to understand it?

 

Much obliged...

 

 

[Jen-in-Wellies]

35 minutes ago, Mike the Boilerman said:

 

 

Could you or Old Goat explain what an a/h is, for the benefit of any newbies struggling to understand it?

 

Much obliged...

 

 

A/h  is amps per hour, so rate of change of current with time. If something on your boat is using say 1A, then 1 second later it is using 1.278A, then the average rate of change during that second is 1000A/h. Simple!

 

Jen

[MtB]

14 minutes ago, Jen-in-Wellies said:

A/h  is amps per hour, so rate of change of current with time. If something on your boat is using say 1A, then 1 second later it is using 1.278A, then the average rate of change during that second is 1000A/h. Simple!

 

Jen

 

Thanks!

 

So, does that mean Old Goat and Alan De E were using the wrong units?

 

Just checking for the benefit of people struggling to understand why a rate of change of current would be used to define energy consumption...

[Alan de Enfield]

9 minutes ago, Mike the Boilerman said:

So, does that mean Old Goat and Alan De E were using the wrong units?

Yes, but by the time I'd noticed it was past the 'allowable editing time'.

You will notice that in a later post (#16) I used the correct units.

[Peter009]

1 hour ago, OldGoat said:

The simple and quick answer - in reverse order to the above is / are

 

Definitely have normal mains 13A sockets "everywhere". I intended to do mobile IBM mini training onboard  and have loads of twin switched sockets. Even though the project never materialised, they're very useful for plugging in the vacuum cleaner up and down the boat. The same applies to 5amp 3pin switch-sockets wired for 12/24v (bad practice- but it's my boat...)

 

Provided that you have a sensibly sized inverter (is it an inverter / charger? or do you have a separate charger?) - 2400W would be nice AND  adequate battery capacity - say 1,000 A/h   then there's no reason why you can't run a high power PC all day long (what do you mean by high power PC - lots of graphics and a super monitor??)

 

If you're making your living from computer work then it's stupid to compromise your ability to work on the move - if you need to....  You may find / wish to do more work on the cut in the future if you realise that it is practical so to do. BUT (grammar) you MUST get the sizing of resources - batteries, inverter, cabling etc, right in the first place

We have a Victron 3000 inverter, to be honest I am only starting to understand how all the power works on a boat and need to have a further discussion with our electrician about this next week, we have 5 batteries and one dedicated for the engine I really do not know what capacity we have or even if our inverter is good enough it was in the boat when we brought it although I am told it is really good by our electrician.  We intend to cruise a lot, maybe not on shore power all the time it is those times when we are not on shore power that concerns me and we may get a generator at some point as that could also be a solution, the nature of my work does involve graphics a lot so I do tend to use a lot of computing and monitors.  

[Alan de Enfield]

13 minutes ago, Peter009 said:

We intend to cruise a lot, maybe not on shore power all the time it is those times when we are not on shore power that concerns me and we may get a generator at some point as that could also be a solution, the nature of my work does involve graphics a lot so I do tend to use a lot of computing and monitors.  

I realise that the budget is not 'bottomless' but whilst the boat is out on the hard is the time to install a generator - it will probably save you £1000 to have it done now whilst everything is 'open' and the boat out of the water.

You can pick up a new decent 5Kva diesel cacooned generator for around £5-6,000, being out of the water means that buying the fitting kit, exhaust etc and having it fitted will probably come in at around £3000.

 

Ideally look for a 1500rpm generator rather than a 3000rpm.

The 3000 rpm are quite noisy even when cacooned.

 

This is the sort of thing, but it is only 4kva and is a 3000rpm model

https://rowlandsmarine.co.uk/paguro-4-sy-marine-generator/

 

https://rowlandsmarine.co.uk/paguro-marine-generator-installation-kit/

 

 

Edited April 6, 2019 by Alan de Enfield

[Pennine]

My solution to the same dilemma was an Acer Revo One RL85, sadly no longer made. It has Intel Core i5, 8Gb Ram, 240 Gb SSD, 2 x 1TB HD, and all in a box 4in x 4in x 6in. Needs 19v dc (PC is 65w, so about 3.5amps) which is provided by a brick from 12v Dc. Never had any issues with voltage spikes. It has HDMI into a Samsung 27in monitor, also supplied via 19v/12v brick. I would suggest investigating Mini/micro PCs to find one to suit your needs. There are plenty models available out there.

[Peter009]

13 minutes ago, Alan de Enfield said:

I realise that the budget is not 'bottomless' but whilst the boat is out on the hard is the time to install a generator - it will probably save you £1000 to have it done now whilst everything is 'open' and the boat out of the water.

You can pick up a new decent 5Kva diesel cacooned generator for around £5-6,000, being out of the water means that buying the fitting kit, exhaust etc and having it fitted will probably come in at around £3000.

 

Ideally look for a 1500rpm generator rather than a 3000rpm.

The 3000 rpm are quite noisy even when cacooned.

 

This is the sort of thing, but it is only 4kva and is a 3000rpm model

https://rowlandsmarine.co.uk/paguro-4-sy-marine-generator/

 

https://rowlandsmarine.co.uk/paguro-marine-generator-installation-kit/

 

 

Thanks Alan would love to but we are moving the boat in 5 weeks to the canals and need all the money we have for that due to cranes etc maybe one day but I think we will not have some money for some time so will have to make do until then

[mrsmelly]

27 minutes ago, Peter009 said:

Thanks Alan would love to but we are moving the boat in 5 weeks to the canals and need all the money we have for that due to cranes etc maybe one day but I think we will not have some money for some time so will have to make do until then

You will probably never have any money again lol. You have chosen to live on a boat, its way more expensive and I mean way way more expensive than living in a house. Its nicer though