Results of laptop efficiency using a AC watt metter

[firstworlder999]

Hi, I'm using a laptop packard bell le69kb with graphics amd radeon hd 8280 and processor amd dual core e1-2500 and by using a AC watt meter I have obtained the following results



30w at idle by using battery + conventional hard disk of 500gb + MAX screen brightness



12w at idle by removing battery + conventional hard disk of 500gb + MAX screen brightness



10w at idle by removing battery + solid hard disk of 240gb + MAX brightness



6w at idle by removing battery + solid hard disk of 240gb + MIN brightness





The efficiency can be further increased by powering the laptop with a 12vdc-19vdc adapter instead using 12vdc-220vac inverter and 220vac-19vdc converter

[rslifkin]

Originally Posted by firstworlder999

Hi, I'm using a laptop packard bell le69kb with graphics amd radeon hd 8280 and processor amd dual core e1-2500 and by using a AC watt meter I have obtained the following results



30w at idle by using battery + conventional hard disk of 500gb + MAX screen brightness



12w at idle by removing battery + conventional hard disk of 500gb + MAX screen brightness



10w at idle by removing battery + solid hard disk of 240gb + MAX brightness



6w at idle by removing battery + solid hard disk of 240gb + MIN brightness





The efficiency can be further increased by powering the laptop with a 12vdc-19vdc adapter instead using 12vdc-220vac inverter and 220vac-19vdc converter

The battery-in power consumption should get much closer to the battery-out consumption once the battery is fully charged. It'll definitely draw more while charging, however.

[firstworlder999]

I forgot


4.5w-5W at idle by removing battery + solid hard disk of 240gb + screen off

Originally Posted by rslifkin

The battery-in power consumption should get much closer to the battery-out consumption once the battery is fully charged. It'll definitely draw more while charging, however.

it should be, but i haven't found a way to test it, however i didn't test full battery and low battery.


when charging a battery there's a percentage of energy loss due to charging inefficiency

[Adelie]

Welcome.

I would suggest updating your profile with your general location and your boat make & model or “Looking” in the "Boat" category. This info shows up under your UserName in every post in the web view. Many questions are boat and/or location dependent and having these tidbits under your UserName saves answering those questions repeatedly. If you need help setting up your profile then click on this link: https://www.cruisersforum.com/forums...ml#post3308797

I would happily help more if the link above is not enough.

Good data. Thx

[jeanathon]

Excellent first post! Do you have any numbers for the 12 vdc to 19vdc? Those ac inverters put out a lot of heat...

[svfinlandia]

Originally Posted by firstworlder999

Hi, I'm using a laptop packard bell le69kb with graphics amd radeon hd 8280 and processor amd dual core e1-2500 and by using a AC watt meter I have obtained the following results

30w at idle by using battery + conventional hard disk of 500gb + MAX screen brightness

12w at idle by removing battery + conventional hard disk of 500gb + MAX screen brightness

10w at idle by removing battery + solid hard disk of 240gb + MAX brightness

6w at idle by removing battery + solid hard disk of 240gb + MIN brightness


The efficiency can be further increased by powering the laptop with a 12vdc-19vdc adapter instead using 12vdc-220vac inverter and 220vac-19vdc converter

Excellent first post. Thank you.
I don’t know why I never thought of testing that but now that I have read your post I will test my Lenova laptop and see how it does.

Al, S/V Finlandia

[Toys_with_time]

Originally Posted by jeanathon

Excellent first post! Do you have any numbers for the 12 vdc to 19vdc? Those ac inverters put out a lot of heat...

I run my laptop on a 12v to 19vDC converter but it gets incredibly hot (and smells hot) when charging and stays fairly hot even when battery is full. I'm on my 3rd one (all generic) and they all seem to have the same problem - maybe undersized windings to keep the cost down? Got one for my partners Mac recently (USB-C) and that gets incredibly hot including the cable but I understand the power drawer on a Mac is very high.
TwT

[flightlead404]

Originally Posted by Toys_with_time

I run my laptop on a 12v to 19vDC converter but it gets incredibly hot (and smells hot) when charging and stays fairly hot even when battery is full. I'm on my 3rd one (all generic) and they all seem to have the same problem - maybe undersized windings to keep the cost down? Got one for my partners Mac recently (USB-C) and that gets incredibly hot including the cable but I understand the power drawer on a Mac is very high.
TwT

I bought two off ebay thinking I could make cheap adapters for 2 of our 4 onboard laptops (still working, sigh).

One was DOA, one crapped out in a few days. Crap chinese junk off ebay.

I'm still interested in doing it properly with good equipment but it looks as though with COVID potentially drawing to a close my days of living/working from the boat will also.

[planetadventure]

I have tried this using my battery monitor Victron BMV-712 and looking at the power pull with my laptop and then with a 26" monitor. Laptop alone through the inverter (which uses power) and the reading was 50.4W. My laptop is an HP Pavilion higher speed laptop with a separate graphics card. With the laptop and monitor going it's closer to 96W. We run our business from the boat so it adds up to a fair amount of power over each day.

[firstworlder999]

Originally Posted by planetadventure

I have tried this using my battery monitor Victron BMV-712 and looking at the power pull with my laptop and then with a 26" monitor. Laptop alone through the inverter (which uses power) and the reading was 50.4W. My laptop is an HP Pavilion higher speed laptop with a separate graphics card. With the laptop and monitor going it's closer to 96W. We run our business from the boat so it adds up to a fair amount of power over each day.

I suggest you to disable the graphic card if possible and if you have an advanced BIOS you can disable some processor cores to reduce laptop consumption.

Also the most efficient display is making a diy projector or retro-projector screen using solar light, this can be accomplished with a used parabolic covered with aluminium mylar plastic and plastic optic fiber to transmit the light to the projector. Also any lcd display can be adapted with back solar light.

Originally Posted by jeanathon

Excellent first post! Do you have any numbers for the 12 vdc to 19vdc? Those ac inverters put out a lot of heat...

To test that you need on DC meter to test before the dc adapter and after the dc adapter. If anyone can do this please post it.

Originally Posted by Toys_with_time

I run my laptop on a 12v to 19vDC converter but it gets incredibly hot (and smells hot) when charging and stays fairly hot even when battery is full. I'm on my 3rd one (all generic) and they all seem to have the same problem - maybe undersized windings to keep the cost down? Got one for my partners Mac recently (USB-C) and that gets incredibly hot including the cable but I understand the power drawer on a Mac is very high.
TwT

You can remove the cover to improve heat dissipation and give a humidity or waterprofing coat to the circuits, or immerse the adapter in mineral oil or coconut oil, which is one of the most appropriate vegetable oils for electrical cooling but you need a way to seal it with vacuum to avoid oil degradation. Oil immersion has been used for high voltage transformer cooling and there are some issues to check as oil water absorption, temperature range and acid scale of the oil that can dissolve some metal thin coats over a long period of time (for example new standard mineral oils are made with acidic petroleum)

[rslifkin]

Originally Posted by firstworlder999

disable some processor cores to reduce laptop consumption.

This will rarely have much effect on real world power use. It may slightly reduce idle power, but any time something needs the CPU above its idle power / speed state, it'll take longer to complete the task and get back to idle, which offsets much of the power gain from turning off some cores.

[firstworlder999]

Originally Posted by rslifkin

This will rarely have much effect on real world power use. It may slightly reduce idle power, but any time something needs the CPU above its idle power / speed state, it'll take longer to complete the task and get back to idle, which offsets much of the power gain from turning off some cores.

That's an assumption of yours because you haven't tested and I have made this thread with tested data. Processor cores are the major energy drain in a computer together with graphic cards, which is more noticeable in computers made for gaming, multitasking, rendering or engineering software.

You can easily change the BIOS advanced options if you are going to use a specific software that requires more processor core capacity or the graphic card. https://www.quora.com/How-do-I-turn-...rd-in-a-laptop

[Sternwake]

I have used a DC inline RC type wattmeter on both my 800 watt MSW, and 400watt PSW inverter, both feeding the original 120vac AC to DC adapter, feeding my laptop whose battery was fully charged, and a 12vDC to 19.5vDC 90 watt converter, whose Ciggy plug receptacle was cut off and replaced with Anderson powerpole connectors.

While the amp/ watt numbers jumped around quickly, the DC to DC converter used on average 7 to 12 watts less than using an inverter to power the original AC to DC converter. The MSW inverter appeared slightly more efficient than the PSW inverter

There is a pretty big difference in load just typing a post, vs streaming video, so my comparisons were on same webpage at same brightness level, vs streaming video or any more CPU intensive task.

My ~22US$ PWR+ dc to dc converter is an older one, but has seen lots of use in the last 10 years. I've read reports that they cheapened the ciggy plug even more, recently by soldering a glass fuse inline, inside.

my DC to DC laptop converter gets no hotter than the AC to DC brick the laptop came with, whether it is on mains power, or inverter. Either gets hottest with depleted laptop battery when streaming video, and both 90 watt ac to dc power brick or 90 watt dc to dc, can draw more than their 90 watt rating.

I have had issues with the DC output cable from brick. There are 3 wires( a Dell laptop) and that third wire would eventually break and the laptop would power fine up from the converter, but not charge the internal battery.

I've replaced this output cord with a thicker gauge, longer one, with better support at barrell plug.

The Ciggy plugs that come with most of these specific laptop 'car adapters' need to be cut off and bypassed with a real connector, if the power supply is rated for more than 60 watts, and even sub 60 watts it is just a matter of time before they fail.

Almost all issues I have read about with dc to dc laptop 'car adapters' is the plug overheats and the fuse holder's spring pushes spring holder into melted plastic and contact is lost on the +.

MyPWR+ DC to DC converter has a 0.09 amp parasitic draw when not hooked to laptop, so I usually disconnect the Anderson Powerpoles when not in use.

If My Dell laptop did not have that pin inside the standard barrel plug, which is required for charging its internal battery, then I could just use a 150 watt DC Boost/step up converter which can be had on Fleabay or Amazon for under 6$.

I did once measure the DC voltage reaching that pin inside the barrell plug, but can't remember exactly what it was, very low though.

Anyway your laptop model number and the terms "car adapter' in the search box should yield a hit on most laptops. Replace/bypass the ubiquitous ciggy plug it comes with for reliability.

The voltage reaching the Dc to dc converter likely plays a considerable part in its efficiency. Stepping up 12.2vDC to 19.5vDC is likely more efficient than 11.2v to 19.5v, due to voltage drop on the undersized wiring leading to/from 12v power port receptacle from battery/ fuse distribution.

I've read many AC wattmeters do not read accurately when a square wave inverter is the source. I've no experience with AC wattmeters.

[firstworlder999]

Originally Posted by Sternwake

I have used a

As you said you can use a dc-dc boost board to power the laptop and that would be the cheapest and long term option because you'll find projects with that board and spare parts.

Also with laptop you can sold a wire instead using the plug that will eventually fail as do the laptop hinges an plastic around them, and in the case of low voltage (both dc and ac) the thickness or gauge of the wire is important to reduce transmission energy loss (there are wire thickness calculators), so you can tie several house electrical wires that will act as a thicker one.

The main aspects of laptops use in sailboats beside weight and portability are efficiency and life cycle. And I suggest to remove the lower case of the laptop and make a big enclosure to improve cooling and to isolate the motherboard from salt water environment and humidity, with some dry desiccant beads in the bottom or just immerse the laptop in oil. In both cases using an external keyboard and mouse.

Most of the laptops fail because dust, hair, etc clogging their fans and humidity and salt water spray ruining the circuits and connectors. For that reason I also suggest making a DIY air desalination and dehumidification ventilation system for the sailboat to remove salinity and humidity inside the boat.

[bcboomer]

Originally Posted by firstworlder999

Most of the laptops fail because dust, hair, etc clogging their fans and humidity and salt water spray ruining the circuits and connectors. For that reason I also suggest making a DIY air desalination and dehumidification ventilation system for the sailboat to remove salinity and humidity inside the boat.

How the heck could anyone possibly do that? What kind of power would it take? Would you leave all the hatches closed?