Advice on off grid solar, desperately needed.

Not-A-Clue

https://www.boards.ie/discussion/comment/120874418#Comment_120874418

Thank you Slave for your reply, sorry for my late response, I'm actually responding to all of you now. You've just made my day!

Because of the advice and suggestions I'd already been given, I realised the generator seemed a more reliable replacement for the windturbine, that you confirmed it, is quite thrilling to read, tbh. (I'm getting there slowly).

I have been looking at ground mounts, I'm not too keen of filling the land with a concrete pad, but noticed 'tree' type legs as a possibility. I am fortunate where my cottage is, as I can put the solar in many places facing in all directions. Thank you for pointing me to CALB and prismatic batteries from NKON, I shall look them up.

I'm not up on inverters just yet, but if one boosts my output, I clearly need to get a basic understanding of them, Thank you.

As to SWMBO ? not a scoobies what that means.

10-10-20

I had to Google that too - SWMBO - She Who Must Be Obeyed!

Not-A-Clue

https://www.boards.ie/discussion/comment/120874597#Comment_120874597

Thank you amzing raisin, sorry for my late reply.

I had been reading up on batteries on several different sites, I'm glad that you have confirmed Lithium as I'd read they had greater longevity, but wasn't 100% sure. A previous poster has suggested I look at CALB and prismatic NKON, neither one of which I had to date heard about. Agreed I'm on a hell of a learning curve🙄.

I had spoken to Victron last year, but they wanted the make and model of all my appliances to know what capacity I would need. I have not as yet got any appliances and although I've looked in several shops, the energy consumpsion on new appliance in Ireland seems a lot higher than the appliances I left behind. I may not be looking in the right shops though.

I will not need anywhere near 10Kw a day. (based on my usage in my last house) however, you have touched on a point I was having difficulty with. I was looking at solar kits (which did not come ready to use and missing a lot of technical stuff). One suggested for a 5KW off grid package I'd need 9 solar panels and 8 x 200A batteries... Because I was worried at the time of electrical build up, I'd wondered if it were better to buy more batteries to capture the excess. The same company offered 5KW wind and solar, but no extra batteries. (That confused me and led me directly to this site, as it didnt make sense). As I've now discounted wind, in favour of a generator. Would it be better to have more storage or not?

On the flip side? I agree! There are just far too many do's and dont's with connecting to the grid. I'm of the opinion that since they themselves disconnected the cottage, they can go sing for my custom.

Thank you for your response.

Not-A-Clue

https://www.boards.ie/discussion/comment/120874608#Comment_120874608

Thank you so much for this link, I shall look into it.

Sorry for the late reply.

Not-A-Clue

https://www.boards.ie/discussion/comment/120875559#Comment_120875559

Hi unkel

The OP is single and no longer a spring chicken toboot.

Having had a few years of thinking about life, it occured to me, either I am loopy or the system is screwed up.

It is my intention to go totally off grid! Whilst I have the use of Wifi at the moment, I will not be installing even that in the cottage.

I'm told my 3G phone will soon be turned off, they claim this is for environmental and green ideals. (Even I'm not stupid enough to believe that statement!).

Why am I doing this? like you say 'not so much to save money'. There is a challenge to it, that's for sure.

It occured to me that the reason I had to work, was to pay for every convenience available, therby giving me no time to enjoy life. I was litterally a slave for the sake of convenience. And as far as I could see what I was paying for convenience, I was overpaying for!

Not-A-Clue

https://www.boards.ie/discussion/comment/120875775#Comment_120875775

unkel, thank you for your response. Youve caught my attention with 14KW of cells? How much energy does one person really need per day? In my last house I was under 2 per day, other than on the day i put the washer on, hoover day, iron day etc.. But I never used more that 3KW at high times. You say you'd have 14 KW cell storage?

On a previous reply to one poster I'd mentioned one company I was looking at, for a 5KW system which said it came with 8 x 200A lithium gel batteries, which I'm certain it claimed held 60KW of useable storage..

As previously stated I have slightly more clue than when i originally posted (thank you) but in the scheme of things very, very little. How can 16 x 320Ah only be 14KWh? I'd really be grateful if you can explain. Thank you.

Not-A-Clue

https://www.boards.ie/discussion/comment/120875973#Comment_120875973

Hello again unkel.

I have been noticing one hell of a difference in costs on just about everything. But as I have no idea what is good or bad, or even what I do or do not need, I am in no position to mention it, until now. I was looking at making a ground mount myself, i have an unrestricted (sun) part of my land which undulates about 30 degrees facing ESE-S-WSW, I had thought to have a curved array, placed on a wood framework literally fastened to the ground over a weed stop sheet. (I do not know if this is a stupid idea, but in all honesty I had thought the land itself could act as a natural mount). Having not seen anything on Google to suggest it had previously been done, I decided I was possibily being rather daft, hence I started looking at spikes instead.. No idea of the cost though.

It was only when I started looking for fixings that I realised @€4.33 plus VAT for one clamp which was absurd, There had to be another way of fastening the panels without being ripped off. (I admit, I thought that!). But because I know nothing, I need to understand 99% more than I do.

the_amazing_raisin

https://www.boards.ie/discussion/comment/120879136#Comment_120879136

Remember a modern charge controller will throttle the output power to the battery when it detects the battery is full

So you won't be overcharging the battery unless there's a major flaw in the configuration

You probably noticed all the appliances energy ratings got worse? That's because the energy rating bands changed, what was an A+ is now a D I think. The label should have the kWh consumption as well so that's what you'd use. Don't worry about being super accurate, you'll probably design in some headroom anyway

Not-A-Clue

https://www.boards.ie/discussion/comment/120878977#Comment_120878977

Thank you for both replies.

Having been on the road for several months, I really started to think, I mean REALLY think! This in turn brought up a lot of silly fears, which I often have no idea where they come from. But they are there so I have to address them.

Electricity, is something I know nothing about, hence I am on here hoping to garner some knowledge from knowledgeable people, who are not trying to sell to me. Hence I'll get many different pieces of advice to help me form an opinion of what I do need.

I will not be having a house alarm. I have to pay someone to call me when it goes off. If Ireland ends up anything like England, I certainly wont get police turning up at the door. If anything is stolen? I doubt the police will look for the culprits, I'll get an incident number, which I would then have to give to the insurance company.

I have no intention of insuring my house. (Im having it renovated to last me out, someone mentioned for the next 40 years, i'll take those years.) In the past I insured my house against absolutely everything. If anything went wrong I put it right, after all I didnt want my insurance to go up the next year. But it always went up! - So why if I never claimed would I spend on insurance? Therein lies a fear we all have, so we insure just incase something bad happens. Why do we assume something bad will happen? surely it is 50% just as likely it wont!

I will not have a TV! it uses electric, there's far too much propaganda on it and anyway, I'm going to be growing food and enjoying life. I wont need one, i'll be doing useful things.

As I said, I REALLY thought about a lot of things and going off grid (other than paying my annual house tax, road and car insurance) is about as much as I'm going to connect to it.

Once I move in? I will have no broadband, telephone etc. It uses electric, I am more than capable of writing a letter. DC999... I'm literally going for it - OFF GRID!

graememk

@Big Lar I think has a ground mount made from old ESB Poles, Looks great. And aint going anywhere!

If building an array for off grid, I'd be going a steep-ish angle pure south, as Summer isnt an issue for power, winter is, SE/SW works really well in summer (early & late sun) but to maximise winter, it needs to be south. Tiltable/moveable added complications, easier just to put up more panels.

Off grid, you need a big battery, as the measure for off grid is how many days you can run without charging. With a 14kwh battery, you possibly could "ride out" a few days of bad weather, and a good sunny day in december you could get your batteries recharged.

Is there any outhouses attached/near the cottage? that could be your "plant room" Where you have the inverters/batteries/generator.

Your learning curve will be steep, but knowing the system inside out will be essential, So when something goes wrong your just not waiting on someone to come troubleshoot.

10-10-20

Personally, I'd stay away from wood and look at unistrut (available at electrical wholesalers) or a custom welded mount. Others may have differing opinions on this, or look at other threads on here for how others have done this already.

Just so I'm clear on your statement above - are you saying that you already have land facing ESE-S-WSW which is pitched at 30 degrees? I'm just confused by the use of "undulates" there, but I think I'm understanding you right. If so, you're very well setup for solar. In that case optimising an array for Winter would be my goal, and given the price of panels at the moment - possibly ignoring the option to have an adjustable array.

I did some rough calcs on this site (I hope my values are interpreted right):

https://re.jrc.ec.europa.eu/pvg_tools/en/#PVP

Select the "Off Grid" option and then input:

• Installed peak PV [Wp]: 10000 (10kW)
• Battery capacity [Wh]: 5000 (5kW)
• Discharge cut-off [%]: 20
• Consumption per day [Wh]: 2500 (2.5kW)
• Slope: 35
• Azimuth: 0 (South)

Review the graphs and values for "PV Output", "Performance" and then "Battery state" yourself.

Here, in my mind, are the critical values:

I see "Percentage days with empty battery" and "Average energy missing" as the critical values here as they tell you what short-fall you're likely to have for the given solar array size (10kW) and battery (5kW). 1% empty is 3 days, but don't forget about prolonged periods where the battery may only get up to 25% (so not defined as 'empty') (Jan and Dec below).

I'd suggest that you play with these figures to find a happy medium as you might find that a slope of 40 degrees is more beneficial for your needs.

Not-A-Clue

https://www.boards.ie/discussion/comment/120878885#Comment_120878885

Hi 10-10-20

I have one neighbour who will be able to see the solar array, no matter where it is placed, either fully or partially. I have 10 acres around the cottage. There are 3 places on the field which I see will get full sun, (no shade obstructions) all year round. Two are flat areas and one is sloping at about a 30 degree pitch and curved in an ESE-S-WSW direction. I had thought (As I mentioned in another reply) that I could use this to have a curved array on a wooden framework on the ground to use the pitch and the curve. But having not seen similar examples, thought it may be a silly idea.

I have a stream to the end of my land, I had thought of hydro, but it is so far away that, as far as I understand, the current would be none existant by the time it reached the house.. I could be totally wrong there as I havent a clue.

Not-A-Clue

https://www.boards.ie/discussion/comment/120879013#Comment_120879013

Slave, How is it possible that an electric car, with the equivalent of 4 windmills as its wheels / tyres. Is not capable of charging itself? Something doesnt add up to me there, I'm sticking with diesel for the mo.

Not-A-Clue

https://www.boards.ie/discussion/comment/120879550#Comment_120879550

hopefully I'll understand what a charge controller is and what it does before long. Yes I had noticed there were far more C's, D's and E's than anything else. Thank you for explaining that.

Calahonda52

OP: get a decent camper van and live in it and rear sheep chickens etc in the cottage and go self sufficient on food from the land

Not-A-Clue

https://www.boards.ie/discussion/comment/120879621#Comment_120879621

Gosh, Thank you so much for that. So correct me if I'm wrong, in order to have 5KW of power stored, I'd need to have 10KW of panels? How many would that be?

This is invaluable to me. I was looking on a site which said in order to go off grid i'd need 9x400W panels and 8x200Amp deep cycle batteries. Which is a foreign language to me! and I couldn't understand why adding an 800W windturbine needed the same amount of batteries as just the solar. Now I realise the batteries may not all be fully charged. Thank you.

Wood, yes my builder said it would rot too soon and this site pointed me in the direction of unistrut on someone else's post.

It will take me a while to understand all the info there, I find it confusing tbh. What is the average energy not captured? is that because of isufficient battery?

Thank you so much for taking the time to do that.

10-10-20

https://www.boards.ie/discussion/comment/120880029#Comment_120880029

So correct me if I'm wrong, in order to have 5KW of power stored, I'd need to have 10KW of panels? How many would that be?

No, I just pulled two numbers, 10kW solar and 5kW batt, and put them in. You could in theory have 15kW of solar and 10kW of battery, whatever fits your need.

What is the average energy not captured? is that because of isufficient battery?

Correct, it's the trade-off of not being on-grid and being able to receive the FiT rate for excess energy.

Not-A-Clue

https://www.boards.ie/discussion/comment/120879586#Comment_120879586

There is an out house, which im hoping to get repaired soon, in which i intended to put the batteries, circuits (generator new addition) etc. etc into, it is only 2 mt away from the kitchen wall.

South facing, that makes sense for the winter, and makes it easier. Thank you.

14KW battery, I've just commented on another post about battery size, it does seem logical to me to have a larger battery, thank you.

Learning curve - It is already steep, but I figure if I can understand the basics first, then graduate to inverters etc. I should be in a far better position than I am now. Its the basics of Amps, Watts, KW which throw me. But bit by bit I'm sure I will eventually understand. Thank you for your reply.

Not-A-Clue

https://www.boards.ie/discussion/comment/120879745#Comment_120879745

calahonda52. Other than the camper van, thats exactly what I intend to do. But I may well build a couple of shepherds huts etc. just incase others like me needed somewhere to put down roots too.

Not-A-Clue

https://www.boards.ie/discussion/comment/120880095#Comment_120880095

10-10-20 Well unless I'm mistaken, I think I'm needing less solar and more batteries. I like that trade off better than conecting to the grid to be honest.

10-10-20

https://www.boards.ie/discussion/comment/120880233#Comment_120880233

Absolutely! But I'm just using numbers to provide a demonstration. I'd suggest 3-days runtime of about 2.5kW in battery sizing (on the basis of ~2kW per day) - so between 8kW and 10kW of battery so that there is some reserve.

Not-A-Clue

https://www.boards.ie/discussion/comment/120880352#Comment_120880352

Thank you, I appreciate your help.

Coltrane

I run a Solis inverter in off-grid mode (disconnected from the grid) without issue.

Worth putting on your list of inverter brands for consideration-generally reliable, cheaper than Victron and with a relatively active second-hand market in Ireland.

10-10-20

@Not-A-Clue :

https://www.youtube.com/watch?v=5sqw7vHwhGU

This system is oversized for your needs in terms of the battery and inverters, but undersized in terms of panels as you have a deficit to make up-for in Winter. Hopefully this helps somewhat.

Not-A-Clue

https://www.boards.ie/discussion/comment/120883388#Comment_120883388

Thank you so much for that, I remember seeing a video a few years back from this same couple, who were explaining the do's and don't's of buying a house in Portugal, so this was a blast from the past!

I will have to watch the technical parts of it a few times, but for now, this has SO HELPED! -

Another poster gave me the link to ART in Waterford for purchase and installation etc. (I am not competent enough to do this myself), Once I've spoken to my builders about getting the small outhouse safe and watertight, I will be contacting him in the hope he works this far up country.

Thank you once again, a really helpful video, which helps explain the AC / DC conversion, which to date has had me stumped.

CelticRambler

As someone who has gone down this path to a certain extent, I would say: get yourself connected to the grid!

Right now, I'm living in an "off grid" situation, thanks to a major upgrade of my motorhome's electrical system last year, and there's nothing better than living day-to-day with a finite battery capacity and limited regeneration potential to push you into cutting your electrical consumption to the bare minimum. Since the upgrade, even when I'm back home, I rarely hook the camper up to the mains now, and the fridge-freezer inside hums away happily for however long I leave it.

I'm also in the process of converting an old chicken-shed and adjacent out-buildings to be my retirement home, and started the project with the idea of having it as an off-grid dwelling, using all the tricks and wisdom acquired from twenty years of motorhoming. But about a year ago, I shelved that idea. Why? Not because of any mismatch between my generating/storage capacity and my carefully worked-out average and likely maximum daily/weekly consumption, but because the more I thought about it, the more examples I found for when that "likely maximum" wouldn't be enough.

If you have no grid connection, then whatever maximum current you've catered for, that's it. You cannot go beyond that, and that means you are forever limited to working below that level, unless you decide to invest in yet more batteries and a bigger inverter and all the gubbins you need to balance loads coming in from additional sources. The biggest culprit in this regard - and something that I have to work around in the camper - is the simultaneous draw of things that you want to have running at the same time - kettle, microwave, fridge and something playing music in the background.

Like you, I live alone, and it's easy enough to manage what switches get flicked and in what order and for how long ... but when I find myself bringing half a dozen willing labourers home for a week, I am mighty glad that they can all be using every power-tool I own at the same time. What I save on that kind of labour more than outweighs the cost of an "always on" grid connection. And even with the renovation works this last year, I still cut my overall electricity consumption by 62% compared to the year before.

You don't know what the future will bring, but knowing you can buy and run just about any single-phase appliance you want without waiting several weeks (or months) for a grid connection is a convenience not to be dismissed lightly.

slave1

https://www.boards.ie/discussion/comment/120879695#Comment_120879695

The laws of Physics.

10-10-20

https://www.boards.ie/discussion/comment/120952723#Comment_120952723

My youngest kid still can't understand why we can't regen all the way down the hill to Granny's and then have enough energy generated to get back up the same hill. I'll submit her CV to Steorn. 🤣

graememk

https://www.boards.ie/discussion/comment/120952886#Comment_120952886

Maybe if you fill your car with rocks you can 😂

unkel

https://www.boards.ie/discussion/comment/120954732#Comment_120954732

Soon Granny will live up the hill instead of down the hill with all them rocks brought over 😂