nowty wrote: ↑Sun Nov 06, 2022 5:58 pm
I love it the way you guys are just going for it.
Was finding this website the tipping point ?
So many things to say, so many points to make...good job I started writing them down last week
I might as well post this here now, for content, and for advice, all of which is welcome.
Finding this website has helped to clarify certain concepts and helped to streamline my thinking (what was more important, where some of hte pit and pratfalls are), but I've been planning on how to cut the energy bill since last winter and I figured out how to limit gas but the issues with electric bills also going up skipped me buy until June. My wife is more focused on how to live a waste free life, but I'm more...focused on the delivery.
Plus it's an interesting challenge.
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HI everyone.
A bit of an introduction.
I’m a renewable energy newbie, looking at how to go from zero, to a fully functioning household that is as close to off grid (ie self sustaining) as can be reasonably achieved, whilst still grid connected.
I’d say that I’m middle aged (mid thirties), married with no kids (a DINK household). My wife and I both work in healthcare in middle to senior positions and live in the suburbs of a West Midlands city/town, and we mostly work from home but do travel around the country for our jobs. We live in an extended 4 bed semi with a south facing (SWS, Azimuth 20 degrees) and drive two (diesel) cars.
We have talked about moving, but the expectation is that we are likely in our forever home, and if we ever did move it would be due to (unlikely and unexpected) fortuitous financial circumstances, so we are looking at permanent solutions to energy usage. One key point is that we are central to elderly family members and we do various ad hoc, odd jobs but also regular tasks like shopping so we do cover a fair amount of ground each week. MInimum is 40 miles/week on family duties, plus minimum of 60 for each day one of us travels, usually over 80 per day.. Some weeks we travel 450 miles for work between us, over the five days but we are usually travelling on different days). We rarely travel more than 200 miles on a day but we do need this facility as a contractual obligation of work (the most we do on a given day is around 400 miles for work).
I’m generally a numbers guy and I do read lots of technical guidance in general, but for the purposes of this post I think it’s fair to make two comments:
One, no matter what tools one uses to make life easier, or more comfortable, it is based on the ability to generate the power in the first place, and
Two, it therefore follows that putting in the effort on step 1 to maximise the usable power generated should pay off every day afterwards. In which case, here are the facts on the ground:
The Roof
The picture that is worth 1000 words: there are essentially 4 roof areas but obviously only the top two are viable. The problem: the sun rises in the right of the picture putting the panels on the side roof in shade for a bit of the day, so Tigo optimisers were part of my planning. Most quotes I’ve had suggest two rows of seven panels, with two on the side roof and five on the main, some quotes suggest less. After some pushing though, and most providers agreed that it is possible to fit a four by four array, with the panels placed landscape; one column of four on the side roof and three columns on the main roof.
There is another problem though:
The Street
Not much I can do about these. Using
Suncalc I know that until December, the trees shadow don’t actually reach the roof, at least not once the sun actually clears the horizon, so the question of if optimisers are needed for panels on the main roof is one I’ve been pondering. The entire street is tree lined in both directions, fortunately though there is a gap immediately outside my house so I am the one person on our side of the road that does not have significant and constant shading. The problem in the summer though is that the chimney would shade quite a few of the panels for several hours so I figure that optimisiers in this instance are probably not a stupidest idea.
The Expansion
This is the garden area. The plan is to build…something…with the posts on the walls. FWIW, the walls are retaining walls so ground level is technically the top of the wall. Looking at 7 posts, 3 at the back, then two in the middle, and two near the house, covering an area roughly 4.5m wide, and 4m deep. Lots of 4.8m length beams and purlins going to be needed, but the plan is to use a pent roof. This is the work in progress, but I have all the timber and plan to get it built by the start of December. This was a quick mock up earlier today (had to move all the timber just to clean the patio a bit)
The posts here are completely freestanding (I put in place simply to see if I could actually lift and position without support, surprisingly easy). I checked and they weigh around 30kg each. But as it is within 2m of a boundary, would this not require they are cut down to 2.5m,
in accordance with permitted development? (Class E, E1, e(ii))
Reading through the permitted development rules prior to buying a house was extremely useful, but there was one thing which always got me: is a pergola a building? It’s not an enclosure (no roof, no sides), it’s not a building (no roof or walls). Therefore I would argue that a pergola is not technically allowed under permitted development at all.
I figured that what I intend to build is essentially a giant cat tower.
…
Yeah, I doubt planning would buy that, but there is a simple solution. The height is measured from the “The height of the building, enclosure or container should be measured from the highest ground level immediately adjacent to the building, enclosure, or container to its highest point”. So the trick is to raise the height of the ground in one area, or to just cut off 50cm from the back three posts and then planning can’t do anything. For context the fence panels are 1.8m high so either way I can get a decent slope. The posts themselves are 3m. I doubt the neighbour on that side cares either, I think the top of the cat tower would be about 30cm higher than the roof of her garage.
So the plan is to cut the posts down to create a slope (taller at the back, shorter next to the house, cut notches to put three joists across and then use six rafters, two per panel,
just how Mr Pablo did on his garage.
This should allow an additional 12 panels, orientated landscape, depending on the panel fixing points. Advice on mounting is greatly appreciated, as are any links to wiring guides etc. As you should be able to visualise from the above photo (taken last year at some point), it will take up a far bit of space. Then there is the cabling to consider.
Some wiser people will notice from these pictures that I do not have access to the side of the house. I am on good terms with by neighbour (an elderly lady, 97 and still going strong) so whilst I could get access for some minor cabling etc I can’t actually use the side of the house for anything else. Technically we don’t have a party wall (the boundary is the line of the fence panels about another six inches out), so vents etc can’t be argued with IMO, or cables on the wall, but anything bigger is just a no. So I need to put any form of exhaust/exchanger unit (ie air to air heat pump) at the back of the house, and there is pressure little room or access
The Internal Layout
This brings me to the greatest problem I think I have. Internal space for the inverter and batteries. The only space I have available is the inside garage wall, near the consumer unit, but I also have a gas pipe fitted that takes up a lot of space as it drops down in the corner, comes across and into to the box where the gas meter used to be then heads off in the ceiling space to the gas hob. The bit that goes straight into the ceiling goes straight into the loft space to the boiler). The loop was due to Cadent cutting me off due to low pressure and once they realised I had built over services then inserted to new pipe at the front of the house and made everything difficult. Damned fossil fuels!
The garage is the first two thirds of the depth of the house, and then there is a back passage to the rear door. The rest of the rear of the house is given to the kitchen and dining room, so there are very few acceptable exit and entry points for cables and other purposes. And this, nowty, is why I’m hesitant to look to air to air heat pumps as a solution without first having a holistic plan in place. Any cabling is going to have to come in the side of the house and then be carried across the ceiling to the internal wall but I’ve got pipework in the way!
The other problem is that the garage is essentially a utility room and the long term plan has always been to get the floor treated, possibly acrylic so it can be moped. Following this, we’d put a worktop in along the wall with the pipework adjacent to the current position, so we have a sink with a draining board and a little bit of worktop, the washer and tumble dryer would rotate 90͐॰, with a tiled splashback (already have the left over tiles, don’t need units just a bit of timber framing so not an expensive project). It is not lost on me that I am “complaining” of limited space yet there are two of us in a four bed house. Still have to move a bunch of stuff though whatever happens.
Alternative options are to install into the loft space, but I do not believe this is viable for a couple of reasons. The main one is temperature, as it gets
hot up there in summer. I mean over 40॰ when it is in around 22॰ outside, and long term I want to keep the option open to expand into the roof space with a dormer to the rear/north facing aspect of the house (and hence leave the solar panels on the south facing aspect in situ. It will also be a bastard getting the batteries up there (but not impossible). Ultimately though, I will be forced to install an unvented cyclinder up here as well so some of the space is earmarked for that (there is a lot of room though).
The Proposals
After going through several proposals, I looked at an installation from Solaredge, who have visited the site and confirmed they can do the install. The proposed plan is the 16 panels plus 4 optimisers(6.4kwp) for the column on the side roof (quote of just below £8,000 for the panels and inverter fully installed and signed off). But the inverter would not be a hybrid and then the cost they have quoted is ridiculous price for a 5.8kw Solax battery (over £4,500!?). I want a stackable battery to go just inside the pillar on the inside wall, so any advice on the…wisdom…of a battery install is also appreciated (yes, Joeboy, I’ve read the thread of the DIY battery, if I tried that I’d blow up half the street and electrocute the other half). It looks like the VAT reduction has simply been taken by all installers as additional profit margin, when I could just buy two Pylontech 5000’s, or three 3000’s which will do me for a long time, or add in an extra of either for a bit more and definitely have enough.
I had a local company offer a substandard plan for solar PV array despite telling them precisely what I was aiming to do. That doesn’t fill me full of confidence in a supplier or fitter TBH. This was a shame because there might have been another two or three jobs in it for the local area.
I’ve ended up going with a national company but then I still need a surveyor visit and I’ll see if they turn around and say “no chance”, but they have offered to fit the 4*4 rooftop array with a 8kw Sunsynk inverter plus
10kw of the Sunsynk stackable batteries for the same cost that most providers are cutting something out (like not only fitting a 3.68kw inverter or half the battery storage etc). Depending on the DNO signoff this might enable me to fit the extra panels before getting an EV and benefit from the better shoulder months and export in summer.
So the other questions I have bouncing around my mind are:
- Are there any issues with the Sunsynk inverter?
- With a second PV array fitted, what steps would need to be taken now to match a DC charger to any inverter fitted ie communication systems?
- Given the potential multiple PV arrays, what would be the best string setup given the potential/planned inverter capabilities? (I’ve got some weird ideas regarding this but then I have no clue about all the rules, and this isn’t actually answerable right now, just posting it as a rhetorical question)
- Longer term, how to fit the condensate lines from a ASHP into the house?
- Where to actually fit a monoblock AHSP?
Cat tax
Both are happy with the proposal for solar panels, provided that it is used to keep them warm. And they don’t have to do any work.
