If ground deploying in uk weather is it possible to have enough panels to heat and cook through winter with solar alone?

[Warpspeed]

A generator should be the last thing on the list, panels first.

Not if you need to go 100% off grid IMMEDIATELY in some wild totally remote location.

Not everyone needs to, or can afford to do that.
If transitioning slowly from grid power to eventually being completely off grid, I agree, generator last.

But if six of you camp on a small island, and plan to live there permanently, a generator and a tent may be about all you have for a while.

 

[zgk51]

For heating? With cloudy weather? No.
As others have already said, your solar panels will make anywhere from 1% to 5% of their normal output on dark days. Maybe up to 10% on medium cloudy days.
For anything that requires more heat than toasting 2 pieces of bread once, you need to burn lgp, wood, diesel etc. (burning it directly, rather than powering a generator which wastes 80% of the fuel's energy).

 

[OM617YOTA]

A generator should be the last thing on the list, panels first.

To build from scratch? I'd rather have the generator so I have power to get things built with. The path from "show up on bare site" to "able to power equipment" is astronomically shorter with a generator.

By the same token, unless you're planning to build a solar array 100 to 1000x bigger than will be needed most of the year(and that's not hyperbole or exaggeration), you're going to need the generator at some point anyway.

Unless that creek really pans out for micro hydro. I'd be looking really closely at that. Even a few hundred watts is an enormous help when it's 24/7 and the sun isn't shining.

 

[12VoltInstalls]

unless you're planning to build a solar array 100 to 1000x bigger than will be needed most of the year(and that's not hyperbole or exaggeration), you're going to need the generator at some point anyway

Truth! Amazing to me, however, is that I only spent ~$60 running the generator last winter (mostly Nov&Dec which were clouded like normal) for my 12V system.
Currently running ~2kW of panels, adding a 400W facing SE to get some earlier amps.

The champion inverter-gen I have was on special ~$500 or something and it’s been 100% dependable.

A good running generator at the very least offers security and convenience. Cheap insurance!

 

[Chispas]

Currently running ~2kW of panels, adding a 400W facing SE to get some earlier amps.

Have you got a build thread ?

 

[12VoltInstalls]

Have you got a build thread ?

No, sorry. It used to be simpler, and solar was my only power (still is) but it was also entertainment to see how much I could get out of bare bones stuff so it morphed oddly from 200W and lead batteries to the present system with LiFePo
These days I’m on to other things and the cheapo system I have just works without me playing with it.

 

[ConnerLabs]

This is a fascinating thread, I would like to add a few things:

Don't overlook passive solar! You haven't started building your off-grid house yet, so it's not too late to design it to maximise solar gain in winter (while avoiding overheating in summer)- this is doable and will achieve the same effect as a big solar array powering an electric heater, but hopefully for less money. Just google "passive solar" to get started...

Wind power- As others have suggested, wind in addition to solar will reduce the odds of you being stuck without power in winter. But won't guarantee it, as it's possible to have several sunless and windless winter days in a row.

Something to burn as a backup. For the reasons explained by others in this thread, the UK national grid will be keeping gas fired power stations around for a long time to supplement its wind and solar. You probably should too.

At a personal scale, the economics boil down to how much do you want to spend up front on insulating your house, vs the recurring costs of fuel to heat it. (Of course with your personal tolerance of cold and misery as an extra variable.) As an extreme example a "Passivhaus" (google this to go down another rabbit hole) needs no heating at all to make its occupants comfortable by definition but costs a fortune to build.

In your situation I would be building a house with lots of insulation and heat recovery ventilation, paying attention to the passive solar design principles but not caring too much about the Passivhaus standard, and covering the whole (south facing, pitched) roof completely in solar panels. I would plonk a wind turbine out the back if the site allowed. The excess PV power in summer, or wind power in winter, can be used to heat water, and electric cooking on PV or wind power would probably be possible almost all of the year, as cooking hardly uses any power compared to space heating. For backup, there have been lots of good suggestions in this thread. My personal choices would be an oil fired boiler and an old Lister diesel generator, which I like to think would run off heating oil too, though I've never tried it.

 

[ThaiTaffy]

My personal choices would be an oil fired boiler and an old Lister diesel generator, which I like to think would run off heating oil too, though I've never tried it.

Kerosene is a pretty good fuel for off grid but the environmental issues if not fitted correctly can be a nightmare not something that should taken lightly though not many special tools are required just experience and some specialist consumables, not sure about the old lister diesel but many modern generators will happily run on kerosene and will actually stipulate they do so in the manual.

 

[OM617YOTA]

covering the whole (south facing, pitched) roof completely in solar panels.

Welcome to the forum!

I'd +1 everything you said except covering the roof with panels. With enough room to ground mount, I wouldn't even consider roof mounted panels.

 

[ConnerLabs]

Welcome to the forum!

I'd +1 everything you said except covering the roof with panels. With enough room to ground mount, I wouldn't even consider roof mounted panels.

Thanks, I guess my thinking was that solar panels are now so cheap and available from builder’s merchants, and they are going on as the house is built, I would use them as the outermost layer of roofing to reduce the spend on building materials. The roof underneath would still need to be waterproof but it could be something cheaper and less substantial, as the panels protect it from direct sunlight, heat and mechanical damage.

I accept that roof mounting makes maintenance harder, but even if most of the panels were ground mounted, I’d use a string of them as a sunshade or veranda type structure to reduce solar gain into the south facing windows in summer. If only because I think it looks cool.

If the goal was to make it through the dark days of winter on PV, bear in mind that the optimal angle for production in a UK winter is more like vertical on a south facing wall.

 

[Warpspeed]

Welcome to the forum!

I'd +1 everything you said except covering the roof with panels. With enough room to ground mount, I wouldn't even consider roof mounted panels.

If you live out in the flat desert and can see the whole clear horizon all around, I might agree.

Most of us have trees, fences, and nearby buildings that can cause shading when the sun is low in the sky, particularly in winter months.
Mounting your panels up as high as possible might give you a couple of extra hours of clear sun very early and very late in the day.
That can make quite a large difference when the days become very short as they do at higher latitudes.

 

[OM617YOTA]

If you live out in the flat desert and can see the whole clear horizon all around, I might agree.

Most of us have trees, fences, and nearby buildings that can cause shading when the sun is low in the sky, particularly in winter months.
Mounting your panels up as high as possible might give you a couple of extra hours of clear sun very early and very late in the day.
That can make quite a large difference when the days become very short as they do at higher latitudes.

Like I said, if there's enough room for ground mount. In the OPs situation, it sounds like there will be plenty.

I know roof mount can be made to work, I know plenty of people do so and are happy with their systems, but I'm not a fan, not even a little bit. I'd accept a LOT of compromises, including happily adding more panels to a ground mount array to make up for losing some time at the top and bottom of the daily generation curve, than roof mount.

In my own situation here, with grid power available, if roof mount was the ONLY option, I'd skip solar entirely.

 

[45North]

Birmingham, for example, is at 52N, which is pretty far north.
So, the short answer is No. You would be hard-pressed to generate enough solar alone to make it through the winter, especially if the skies are overcast.

 

[45North]

Edit: Or, putting it another way: it would be prohibitively expensive to build a system big enough for those conditions.

 

[Warpspeed]

Plan your solar system for optimum mid winter performance.
Summer will take care of itself.

 

[teal95]

Don't forget cloud cover. Where I'm at in southern Michigan we have persistent cloud cover from early November until mid January (when Lake Michigan finally gets enough ice cover to quit generating the clouds). Under cloud cover you want the panels horizontal to see the maximum amount of sky they can. Yes, you're only getting 10% or less of the output but it's better then what you get with the panels vertical when half their field of view is dark ground.

So you have to balance aiming with some statistics of cloud cover vs sunny days and also weigh in snow cover, which makes vertical even with horizontal on cloudy days.

I've had an 8kW ground mount system for 5 years and last year added another 20kW roof mounted on my barn that's 4/12 pitch, so pretty flat.

 

[ThaiTaffy]

That's kinda what's great about solar in Thailand we get cloud cover in summer with monsoon season so the light intensity is still high even when it's raining and miserable then winter when intensity is low it's dry and clear sky's. I think @Norwasian has found out he over paneled thinking the monsoon would lower his production far more than it actually has.
Growing up in the valleys of South Wales the sun was primarily behind a hill or a cloud which was likely the reason I was never that interested in solar if I was living on top of the Brecon beacons above the mist line it might have been far more viable.

 

[SeaGal]

Growing up in the valleys of South Wales the sun was primarily behind a hill or a cloud which was likely the reason I was never that interested in solar

And there was me thinking the real reason that you were never that interested in solar was that PV panels hadn't been invented when you were growing up

 

[ThaiTaffy]

And there was me thinking the real reason that you were never that interested in solar was that PV panels hadn't been invented when you were growing up

I'll let you in on a secret PV panels are atleast 10 years older than me

 

[SeaGal]

I'll let you in on a secret PV panels are atleast 10 years older than me

I just checked and "me too"... "1954 Photovoltaic technology is born in the United States when Daryl Chapin, Calvin Fuller, and Gerald Pearson develop the silicon photovoltaic (PV) cell at Bell Labs"

 

[mikefitz]

I just checked

Discovered a bit earlier than 1954, 1839 is the first discovery

Edmond Becquerel - Wikipedia

en.wikipedia.org

First practical solar array, 1884,

Charles Fritts - Wikipedia

en.wikipedia.org