Solar panels for tenants?

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Solar panels for tenants?

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NorthernMonkeyGirl

Joined: 10 Apr 2011
Posts: 4630
Location: Peeping over your shoulder

Posted: Fri Apr 01, 22 11:03 am Post subject: Solar panels for tenants?

Seeing my electricity debit double put me in a mood. Last time I looked at solar energy, you could either womble together something to charge your phone, or you could have a fully professional, grid-linked system.

Is there a semi-mobile middle ground? E.g. poking about https://www.greenbee.org.uk/gbk021---heidi-special---350watts-of-solar-and-a-500w-inverter/?Page_ID=3610&refpid=&id=917453 . If I safely installed a cable and couple of plug sockets in the house, would it be capable of running fridge, freezer, laptops? But not a standard oven or shower? But maybe one of those instant pots being discussed in another thread?

I'm just trying to work out if any of this makes sense for a long term tenancy (5+ years) without fastening to roof or connecting to grid.

Or, given the cost of standing charges, would it be not as useful as it seems?

dpack

Joined: 02 Jul 2005
Posts: 46210
Location: yes

Posted: Fri Apr 01, 22 2:39 pm Post subject:

lap top might be pushing it, no idea about cold boxes

my photo capable lappy ate a 120ah leisure battery in about ten hours

via an inverter to 240v ac and then its own transformer power supply lead to 19v to the internal battery and/or to the internal power converter thingys is wasteful

the less transformers and inverters the better, the 30%s soon add up

a panel, battery bank, usb feed has minimal losses and does work

350w would run quite a lot of low load stuff(assume you might get half or less of the 350w on warm dark days)

a thing to consider is cold boxes are not a constant load which can be a bit iffy with battery and inverter rigs, any motor will have a start surge regardless of its numbers on the booklet

led lights, usb charging etc seems a good way to use a low power and "free" supply that will fit in a van when you move

ps 350w is not much to play with once losses from transformation and transfer are factored in

i recon keep it low voltage from panel to load or go for a big rig and absorb the losses, the former is easy to move when you move

my stuff is 4 panels that fold up to about A4 size, they knock out quite a bit of usb voltage and power either direct or into the small battery bank and are fine for phones, kindles, lights, a aa aaa rechargeable batteries that fit many things

the battery bank inline is best as a cold sunny day does get a bit frisky on voltage
the whole kit fits cabin size luggage and has enough power for many low voltage things including the camera
less than 5 kg with loads of loose batteries, wires, plugs a good meter and a few bits of small tool kit in case wires do not fit and a couple of decent capacity battery bank in a box things for darkness etc

if you go that route get a battery bank as a buffer, a chip and a few cells in a box is far more expendable than a fried phone or tablet
do individual batteries direct with a proper charger

iirc my full kit was under £250, no improvisation so far, but i did get assorted plugs and wires etc that are compatible and worked the specs based on requirements(usb voltage and power, anywhere, for any "mouth", portable and with reasonable control gear built in)

for an often nomadic lifestyle, that sort of thing is far more sensible than trying to use a 240 v up and down for assorted big loads as a fixed rig

it will sort all the little things that waste power and money by going from 240v 50 hz to usb level or lower

check out folding solar panel camping usb look to spend a bit under £200 for a good one with a decent build quality, output and assorted compatibility,built in control gear and a few ports
they have gone up a bit, the cheap ones are carp rather than electric eels

they may have half the capacity on paper than the thing you mentioned but it is far more use than trying to power big stuff on a smallish stand alone rig that may run the things they mention for a smallish van

boat and van stuff is worth looking at, that one looks like a load of expensive kit that may not be the best use of PV investment as it is trying to bridge the gap between houser 240v and pv harvest at a small scale

the less boxes and wires the better

ps apparently my portable rig should power a modern low power standard domestic lappy until it got light again, i have not tried that yet

the one you spotted might have trouble with this pooter on a sunny day and even with 2 batteries unless they are surge capable like a car battery and slow use like a leisure battery even a normal size fridge might be an issue

sorry to ramble, work out what you should best invest in in terms of outlay and savings as well as harvesting some non fossil leccy where you need it

ps load end domestic stuff that fits in vans and boats is often made for that sort of thing

pps the pv that fits on top of vans etc is usually in tandem with harvesting 12v when the engine is running and a larger battery capacity would be wise

dpack

Joined: 02 Jul 2005
Posts: 46210
Location: yes

Posted: Fri Apr 01, 22 2:54 pm Post subject:
re saving energy on bills a ghillie kettle will pay for itself in a couple of months etc

NorthernMonkeyGirl

Joined: 10 Apr 2011
Posts: 4630
Location: Peeping over your shoulder

Posted: Fri Apr 01, 22 5:22 pm Post subject:

Not rambling! All useful. I glaze over a bit with technical specs that don't "translate".

Looking at the constantly used things, I have some light and heat for reptilian critters, work laptop set-up including second monitor that stays plugged in, home laptop that is charged and drained, couple of charging gadgets, then built-in stuff (current house is all electric): fridge, freezer, kettle, oven, shower & fan, lights.

It didn't seem to make sense to convert solar to 230/240V with a transformer, then re-transform it back down through normal laptop adaptor.

I will keep pondering!

dpack

Joined: 02 Jul 2005
Posts: 46210
Location: yes

Posted: Sat Apr 02, 22 9:47 am Post subject:

Quote:

It didn't seem to make sense to convert solar to 230/240V with a transformer, then re-transform it back down through normal laptop adaptor.

spot on, up or down with voltage and from DC to AC or the converse has an energy loss

the movement of energy has a loss, these vary depending on distance, AC or DC, V and A and resistance (ie the equipment runs warm, the wire is on fire is just an under specced wire

)

minimal conversions and minimal transfer distances seem very important with small harvests, with big ones inefficiency is considered irrelevant

with a fully LV rig for the things that eat LV you do get to use a bigger percentage of the harvest and avoid inefficient use of expensive 240V AC from stepping down to LV DC
at the mo that is probably best value for investment

as a wild card, a micro solar thermal rig might be ideal for reptiles but i dought there is an off the shelf version more technical than swapping black rocks from a mini greenhouse in the sun to the tank

Nicky cigreen

Joined: 25 Jun 2007
Posts: 9881
Location: Devon, uk

Posted: Sat Apr 02, 22 11:42 am Post subject:
I have, in the past, looked at solar heat lamps for chicks - essentially a solar panel attached to a heat lamp.. - I wonder if you could set up something for your reptiles? you would probably need back up lecy for when min temps weren't reached, I guess if they are on a thermostat?

dpack

Joined: 02 Jul 2005
Posts: 46210
Location: yes

Posted: Sat Apr 02, 22 12:44 pm Post subject:
for low temp warm, clear and black box outside in the sun, pipes, pumps, insulated tank, warmer place for seeds or reps use water or water plus for better specific heat capacity tiny pv LV can easily run small pumps and hose etc is cheap

dpack

Joined: 02 Jul 2005
Posts: 46210
Location: yes

Posted: Sat Apr 02, 22 12:46 pm Post subject:
ps the control gear might need a little thought, cooked or cold reps is bad

Mistress Rose

Joined: 21 Jul 2011
Posts: 15967

Posted: Sat Apr 02, 22 7:25 pm Post subject:

We use a solar panel in the woods that folds up. Not sure of exact size, but about 1m x 1/2m folded. Has a carry case that I can easily carry, so not too heavy. We use it to charge a leisure battery in the solid shelter or trailer, and in the trailer it runs a freezer box, 3 LED lights and a phone charger. The solid shelter battery is enough for 3 lights and is stable enough to recharge my Nintendo. We also have a low powered electric radiator in there, but that does drain the battery a bit quick.

Slim

Joined: 05 Mar 2006
Posts: 6612
Location: New England (In the US of A)

Posted: Sun Apr 03, 22 10:31 am Post subject:

For a fully electrified setup, I think it's going to feel like a lot of work to just nibble around the edges of supplying small loads.
The same money may be better invested in seeking efficiencies and reducing demand, even if only for small amounts, the cost reduction will add up over the years....
The cheapest electricity if typically reduced demand rather than a new supply source.
But that's just a guess, and doesn't circumvent any other positives associated with doing some of your own solar (satisfaction, education, etc. I think folks playing with small amounts of intermittent supply often become masters of efficient usage)

Over here there are community solar purchasing arrangements that wouldn't require you to physically host panels - no clue if something like it's available to you?

NorthernMonkeyGirl

Joined: 10 Apr 2011
Posts: 4630
Location: Peeping over your shoulder

Posted: Sun Apr 03, 22 12:21 pm Post subject:
Hmm not sure. All speculative based on the slim chance of moving house in summer (watch this space!). I've gone down a youtube rabbit hole a bit, and am now thinking perhaps insulation of house, solar hot water, and heat-storage-in-a-greenhouse would be the most cost effective / relatively amenable to DIY? I have found a chap who reminds me of Fred Dibnah though!

Slim

Joined: 05 Mar 2006
Posts: 6612
Location: New England (In the US of A)

Posted: Sun Apr 03, 22 12:31 pm Post subject:

If I were you, I'd look to figuring out how to reduce power needs for the things you may bring with you. If heating reptile enclosures, is there a way to improve their insulation without negatively impacting other aspects like airflow?

If using electric heat, is it worth investigating the Japanese approach of the heated table with surrounding blanket to keep just you cosy while allowing the rest of the space to be a lower temperature? (I forget what that's called)

NorthernMonkeyGirl

Joined: 10 Apr 2011
Posts: 4630
Location: Peeping over your shoulder

Posted: Sun Apr 03, 22 12:46 pm Post subject:

... like the polystyrene insulation from boxes that I threw out last week...that would have worked

it was only stashed away for the last 18 months. They are in tall skinny tanks with ventilation gap at the front and open mesh lids - lots of scope to wrap them up in something. Thanks for the nudge, should have considered that sooner!

Full review probably a good idea, for now the inefficient appliances are at least kicking out some heat in to the house! (PS my freezer is stuck on -35 C, that seems excessive)

dpack

Joined: 02 Jul 2005
Posts: 46210
Location: yes

Posted: Sun Apr 03, 22 3:18 pm Post subject:
minus 18C is considered normal for domestic bought and rotated by dates stuff minus 25c is good for an extra year on fish or meat etc, that can pay for itself if the shopping was done well, minus 35c is unusual and it will be expensive to maintain a 50 or 60 degree difference between in and out of the box

Mistress Rose

Joined: 21 Jul 2011
Posts: 15967

Posted: Mon Apr 04, 22 7:14 am Post subject:

Slim, you are right about minimising use of power from solar energy. When we are in the woods we try to use the lights as little as possible; reading by the window, only turning the light on when we make tea so we can see the level of water in the cups etc.

Lagging the reptile enclosures seems a very good idea. The old way, before central heating, was to just have one room warm enough to sit in using a fire, wood in your case.

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