Mains Inverter.

[PPrep]

Or for the UPS idea, something like this. The batteries are the standard ones available for stairlifts etc.
https://www.criticalpowersupplies.co.uk ... s-npw-600/

This looks like a very good option if I go for a UPS, and is comparable in price to the inverters I've been looking at. This is a better choice than an inverter for various reasons.

[PPrep]

Ditto all the posts above.
Square waves should be fine. 1000w probably overkill, but as you say, what will hold a lot will hold a little . Consider getting a mobile hotspot or a spare phone for internet resilience as any outage might take out your local mast and good to have multiple networks available

Having multiple networks available is a good idea. A hotspot can be a good option, but the problem is the monthly payment which will be expensive over time. I have a spare phone, but this shares a SIM card with the "main" phone. I rarely use a phone at all and use a pay as you go service. My costs are about £1.80 per month on average.

[GillyBee]

I keep a live PAYG card with Lebara which allows me to swap in and out of a 30 day rolling contract at will - unlimited data is £25 for a month with no need to commit to longer. Or if the data need is less a fiver will get you 5GB - but that won't go very far with video.

[jennyjj01]

I keep a live PAYG card with Lebara which allows me to swap in and out of a 30 day rolling contract at will - unlimited data is £25 for a month with no need to commit to longer. Or if the data need is less a fiver will get you 5GB - but that won't go very far with video.

I have a Tesco PAYG sim for a spare phone/hotspot. It has been allowed to stay in service with some residual credit for over a year without being used at all. Some networks expire their payg sims.

Thumbs up for lebara. I have a PAYG lebara which can be topped up for as little as a fiver. Just make one text every few months to keep it alive. Contract lebara starts at a fiver a month.

Tesco=O2
Lebara=Vodafone

For the mischievous minded who know what a burner is..., Lebara is one of the few networks where ALL top ups can be cash bought vouchers with no need to give ID ever.

[PPrep]

Thanks for the advice on hotspots. It's good to know one can get a PAYG SIM that doesn't time-expire. I'll look into this further.

Lebara seems to be the best bet for me.

[tarmactatt]

Just some thoughts which might help, I'm not criticising and I'd love to do something similar one day.

Your setup might be a little light for what you want to achieve.

150Ah batteries at, I assume, 13.5V = 2025Wh

Just for some ballpark numbers, I've used an online calculator (solar Wizard.org.uk) to calculate solar resource for a south facing roof in London (st Paul's Cathedral).

180W panel in the months of Nov, Dec, Jan will collect c.2KWh/month.

Daily consumption:
80W laptop used for 1 hours/day for a month = 2.48KWh month
Router/modem, you don't say if you only want this powered for use with the laptop or you also have a smartphone. 15W for 1 hour/day for 1 month is 465Wh, or, for 8hr/day for a month is 3.71KWh.
Auxillary devices, radio, lights, charging phone, etc, say perhaps you use a USB outlet for 2 hours a day for charging, this is 10W/day, 310Wh/month.

Total, demand 3.25KWh/month leaves you with a deficit of 1.25kwh/month during these months.

On the flip side, during May, Jun, July, the calculator thinks you can get c.800Wh/day, or 26KWh/month..!

Of course, you can reverse the calculations to work out how many hours of laptop you can "afford" while off grid.

[PPrep]

Just some thoughts which might help, I'm not criticising and I'd love to do something similar one day.

Your setup might be a little light for what you want to achieve.

Of course, you can reverse the calculations to work out how many hours of laptop you can "afford" while off grid.

Thank you for your helpful calculations.

I have planned to be flexible about power usage; this will be seasonal to an extent. I've experimented with solar power since the late 1980's, and have found that solar panels are practically useless (unless you have a lot of them) during the Winter months - shorter days, dimmer light and more fog are the main culprits. At any time of year their output is highly variable, relatively speaking. My daily consumption would also be variable. The Winter months are when I'll only be able to power a laptop for an hour once a week, perhaps. This is mainly for the Software Defined receiver; I would have to use my short wave receiver for news. This is digital and has very wide coverage, whilst being very economical on power.

[tarmactatt]

Numbers will be slightly better south of London and slightly to significantly worse as you go north. One of my thoughts about my future solar set up is that invariably the s*** will hit the proverbial in the middle of winter....

80w laptop just for a SDR seems quite a lot, have you looked at alternatives, raspberry pi for example? I've often been tempted by the low cost RTL-SDR dongles just to have a play but not got around to it yet- recieving and processing the weather satellite data blows my mind!

You mention you have a SW receiver, would the SDR actually be more "powerful" for news reports than a digital radio? I've looked at the XHDATA D-808, it gets pretty good reviews and runs off a single battery and is rechargeable.

Just some ideas, it seems the laptop is a luxury and actually you're pretty well set up already!

For what it's worth, I did back of the envelope calculations for manual "crank dynamo" type devices and the amount of work they require to get useful energy out makes them impractical in my view.

[Peter]

Our 240w solar will be enough for the AA/AAA rechargeables and USB devices (lights, radios etc) but not much more .

[pseudonym]

Our 240w solar will be enough for the AA/AAA rechargeables and USB devices (lights, radios etc) but not much more .

Every little helps.