Newbie solar DC power/laptop question

[shinobidef]

I’m planning my solar setup but I’m a bit confused with laptops:

I read somewhere the other day that laptops are generally DC so what’s happening with a solar power setup is that DC current comes in, an inverter converts this to AC, then the transformer box on the laptop charger converts the AC back into DC again, thereby losing efficiency.

If this is correct, is it not possible to somehow connect a laptop directly to the DC? Essentially, all our other appliances will be running off DC so seems to me that it would be a complete pain to just buy an inverter to run two laptops.

I’ve read some posts about people charging laptops off the alternator but as there will be times when we’re not driving anywhere and I have no idea how long it would take to charge a laptop this way, I’m not sure how viable this is. I’m buying a Chromebook purely for the battery life but my partner doesn’t get a lot of juice out of his!

Thanks in advance.

[Darren]

Hi
Hi

You are right. The easiest thing to do is to buy a 12v laptop charger. This will charge your laptop from the 12v DC system you already have, and not required the inverter.
You are also right about the alternator. When the engine is running it is generating loads of 12v power, so use this to charge things.
I’d highly recommend a split-charge relay to charge you leisure battery from your engine battery.
When your engine is running you can charge you laptop using the 12v charger still.

[Darren]

Hi
Hi

You are right. The easiest thing to do is to buy a 12v laptop charger. This will charge your laptop from the 12v DC system you already have, and not required the inverter.
You are also right about the alternator. When the engine is running it is generating loads of 12v power, so use this to charge things.
I’d highly recommend a split-charge relay to charge you leisure battery from your engine battery.
When your engine is running you can charge you laptop using the 12v charger still.

[shinobidef]

Brilliant – thanks Darren.
Brilliant – thanks Darren. Yes, I’ve got a split charge relay down on my parts list. Do you know how I work out which amperage I’d need? I’m looking at 2 x 225 Ah batteries and 2 x 100W solar panels. I’ll also be getting an MPPT controller.

In terms of the laptop charger, should the laptop have a maximum voltage listed on the back panel or do they pretty much tend to cover all models? I guess my partner will be nervous in case there’s any power surges but I’m assuming the controller will take care of that.

Presumably I don’t need an inverter to use an onsite electric hook (just a mains charging unit like this? https://www.amazon.co.uk/gp/product/B004TLF53S/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=B004TLF53S&linkCode=as2&tag=jugglingpirat-21

Thanks again – much appreciated.

[shinobidef]

Brilliant – thanks Darren.
Brilliant – thanks Darren. Yes, I’ve got a split charge relay down on my parts list. Do you know how I work out which amperage I’d need? I’m looking at 2 x 225 Ah batteries and 2 x 100W solar panels. I’ll also be getting an MPPT controller.

In terms of the laptop charger, should the laptop have a maximum voltage listed on the back panel or do they pretty much tend to cover all models? I guess my partner will be nervous in case there’s any power surges but I’m assuming the controller will take care of that.

Presumably I don’t need an inverter to use an onsite electric hook (just a mains charging unit like this? https://www.amazon.co.uk/gp/product/B004TLF53S/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=B004TLF53S&linkCode=as2&tag=jugglingpirat-21

Thanks again – much appreciated.

[Darren]

That is lots of battery power
That is lots of battery power, and will be plenty for you, I think.

The laptop will probably have a sticker on the bottom showing voltage, or check the charger.
Then buy a 12v charger with the same voltage. Most are 19v.

Yes, you can use a battery charger like you’ve listed, that’s fine.

[Darren]

That is lots of battery power
That is lots of battery power, and will be plenty for you, I think.

The laptop will probably have a sticker on the bottom showing voltage, or check the charger.
Then buy a 12v charger with the same voltage. Most are 19v.

Yes, you can use a battery charger like you’ve listed, that’s fine.

[Author]

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