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My biggest use of electricity is my laptop and monitor.

Any ideas on a portable solar panel that could power those during the summer? Portable because I rent and can’t fix anything down, it doesn’t have to fit in a backpack or anything like that.




That’s…really surprising? A ceiling fan uses about 75W a hour. A MacBook Pro has a 100 Wh battery and last about 4 hours so 25W per hour. Your laptop and monitor should be lower than any other appliance.

That being said, there’s a lot of options nowadays which is exciting! For instance, you could have a 200W port panel and a 1kWh battery system from eco flow that should run both with room to spare. Anker has a new system meant for patios but it’s only for Europe.


I run my MacBook Pro off of the usbc pd port on my cheap ($130, 300wh) lifepo4 battery box. I got 2, plug one directly into a 100w solar panel, other powers the computer and monitor. Swap daily.

If you want to run a line into your house you can get by with one, or just get a panel with a usbc pd output.


>75W a hour

Just 75W.


Yeah, it’s gets a bit murky to stick with power or energy even though Wh isn’t SI. But it’s usually pretty important to keep the time component when it comes to describing an energy storage system.


Minute, hour, day are specifically allowed by CIPM to be used in SI. They just can't be used with prefixes.

kWh is obviously inconsistent with SI conventions if commonly used; but 'kW⋅h' or 'kW h' is completely acceptable. As is 'W⋅h'

A full list of acceptable non-SI units can be found in the brochure here under: "Non-SI units accepted for use with the SI units"

https://www.bipm.org/en/publications/si-brochure


Watts per hour are not a unit of power or energy. Watts are power. Watt hours are energy.


Joules are energy


They are both energy. Watts are Joules/seconds so if you're dividing by time and then multiplying by time (an hour in this case) they obviously cancel out and you end up back with just Joules.

Specifically 1 Watt-hour==3600 Joules.


75 watt-hours per hour then, if you must…


Portable panels are almost never used in a way such that the carbon emissions it took to make them are offset. Things like how many hours they are used, poor exposure and curtailment from the use of batteries all slash the useful electricity they produce.

For almost all people they are only appropriate when you are off-grid.


Seems like the easy solution is one of those solar systems marketed as being for camping, right? Not sure it's economical, but easy.

Personally I'm interested in a DIY mod to add solar panels directly to the back of a laptop screen. It probably wouldn't be able to actually charge unless the machine is in sleep mode (which also would have the lid closed which would help), but it would extend the battery - if the machine averages 10W and the panel gives 1W, that's an extra 10% runtime for free, and better if it sleeps in the middle (which works, because I'm unlikely to use a laptop continuously for 10 hours).


> Not sure it's economical,

Or environmentally sustainable?

A solar panel has life-span of 25-30 years, will you be utilizing that? or are you just creating more waste?

If you wanted to protect the environment, it's probably better to find a wind-farm project or solar farm project to invest in.

It's really easy to think that adding solar panels everywhere is a good idea; but you might just be making e-waste.


I don't see where OP said they care about the environment, though.


Your fridge is probably using more power, unless it's a fairly new, highest-quality European market model.

(The range at the local big appliance retailer is about 35W for the cheapest models to 10W for the most expensive.)


You don’t have a fridge or a water heater or a stove or a fan?


Ecoflow and others do battery and invertors with solar connectors for such a system. Much of their range allows up to 800W of solar panels and all in would be about $1500 total with 2 panels and that gives you 2KWh or so of battery storage. Your typical usage for a high end monitor is maybe 130W and laptops vary but almost certainly below 100W typically.


Something like this https://youtu.be/UnTJScmSLYs Eco flow can charge from solar, then charge a few appliances. I think Anker just released a similar product.


How comfortable are you with DIY electrics? Can you lay out a panel somewhere in the sun? Do you want it to run at night? Do you want it to automatically switch to grid power if needed?


Ditch the monitor and get some AR glasses like Viture or Xreal




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