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Do you include the wife in that category as mine uses the smoke alarm as the timer.

I'm doing a “no-combustion” house. Meaning it doesn't burn stuff like wood, oil or gas and doesn't use mains electricity (a lot which comes from burning stuff). Well-insulated not-so-large house (~= 0.1 W/m²·K, good airtightness) with sufficient but not excessive windows. 6 kW of PV. 10 kWh of lithium iron phosphate batteries. 6 or 8 20x47 mm solar thermal panels (I've bought 8 but may only be able to fit 6 or 7 while allowing fire escape from the two bedrooms). Probably a small wind turbine but not decided what sort yet. Large (10m³) thermal store inside the house for space heating bordering on inter-seasonal storage. I'm a big believer in mixing wind and PV. There are lots of dull days and lots of lulls in the wind [¹] but it's very rare for a dull lull to last more than a day or so. Will that be sufficient “without a very large compromise in terms of living”? I hope so but ask me in a few year's time. I suspect 9 months of the year will be easy, December, January and February will be comfortable with a bit of forethought - look at the forecast and the state of charge before doing washing or cooking something that takes a long time. We'll see. OK, a backup generator's likely but I'd consider it a fail if it's needed more than a handful of times a year. [¹] Although I'd have made a bit more progress on the build this year if there'd been a few more lulls.

just a little something to keep @Onoff going. The result of my grouting yesterday - still a lot to do but it looks a lot better now.

Hi guys, Just joined this group. Just finished building a Passivhaus in Penzance, Cornwall. My friend and I built 2 houses together, one for each family on a challenging plot chasing the passivhaus dream... We've been in the house since end July and just seeing how it copes with our first winter! So it's a timber. Frame design, sitting on a concrete raft (on 30cm insulation!) planned using the PHPP software to conform to PH standards. So it's super insulated, airtight (0.3ac/hr) no cold bridges, triple and quadruple (skylights) glazed with Brink MVHR system (ubbink plastic duct and plenum). My friend developed the wall buildup himself to achieve the PH standards without us having to buy premade PH timber frame sections, saved us a lot of money... Biggest struggle so far, trying to get the. Brink post heater to operate... It's wired up correctly but won't operate, even at high fan speeds...? Which is really why I joined this forum, to hopefully glean some info as our supplier hasn't solved it (or Brink at this stage!) Cheers.. Murray

Please tell me you swung your leg up onto the conveyer whilst wielding your Swiss thus revealing your red soles. Or did you just high kick the said security tag into the veg isle thus thawting the person who bought a lowly security enabled cucumber? That will learn those closet Hendrix drinkers

Yes, but I'm a girl and highly value the fact that my red Victorinox matches my red duffle coat. Decus et tutamen est.

I’m probably the wrong person to be pondering this, as I’m not a tech guru but why didn’t Sunamp just make a little bolt on box containing a Willis heater and pump for the ‘e’ variants?

+1. There's some proper weirdos on here...

I have 4 oversized bins. (All for a one off delivery charge of £20) 1 grey - general rubbish 2 brown - bottles, tins and plastic 3 blue - cardboard and paper 4 green - garden waste - only collected between spring and autumn equinox. Despite the fact there is only me all the bins are the largest domestic size. My old house and my neighbours have only the garden bin at that size, the generall rubbish a size small and bottle etc and card etc smaller still. If my neighbours hadn't been so arsey I would have offered them a swap as they regularly overfill both the bottle bin (lots of beer cans, wine bottles and pop bottles) and the paper and cardboard bin (takeaways many nights a week) and they are a family with 2 kids and a baby. Since they don't even have the decency to be polite they can get stuffed.

Wyre Borough - £22. We do, and they don't mind...... Very nice lads, very very nice lads

Makes you wonder .... Product engineering would have said that a single module type was the way to go, and then modify the heat module per “charge type” so that you reduce the variations. With this arrangement you would end up with some sort of “PV Boost Box” that could just hydraulically provide the heat into the units, and could even be provided as an add on to existing units where PV was added at a future date. It would only need a pump, valve and heating element, not exactly difficult to engineer ..

Who mentioned solar thermal? Rub it in why don't you!

Yes, exactly that. Well at least it will be when I finish it The bottom draws open to a flat shelf which lifts up for storage.

Yes, the design is key. The carcass is 25mm with additional reinforcement in various places with the whole thing bolted to the wall.

Back on the subject of washing...... Consider mounting your washer and dryer higher up if you have the room. Makes it so much easier on the back! You need to design the carcass/units well as it’s subject to a fair amount of vibration if you’ve got your big pants on a 1400 spin Heres mine and I don’t think I could go back to ground mounted.....

Just looking at the product range, it seems that there has been a gradual shift away from a focus on making more effective use of energy from domestic scale renewable generation and towards becoming a competitor for conventional hot water storage systems. I'll freely admit that I hadn't noticed this shift in emphasis in the time since we first fitted the Sunamp PV. I think that one issue may be that product R&D may be being spread a bit thin as a result of the many different variants being brought to market at the same time. Just from my personal observations, the old Sunamp PV was a better engineered and finished product than the newer UniQ; just a glance at the unit when it was first unpacked highlighted this. The eHW may well be able to be fine tuned to overcome the shortcoming in it not being able to utilise excess PV generation charging very effectively, I don't know. I hope that some further development of the Qontroller is able to overcome the present inability to accept charge until the unit is ~50% discharged. I have wondered if the designers may have just missed the need to be able to store charge for use further ahead than the next 12 hours. In winter, it's important to be able to store energy whenever it's available, so that it can be used 24 to 48 hours later, avoiding the need to use grid energy. Unless you've lived with PV for a while, and seen the high degree of generation variability during the winter months, then you may not realise how important this ability to maximise energy storage for later use is, if, say, the next day is cloudy.

You could well be right, and ive not really noticed any change on "normal" houses. Just the sort of stuff im interested in. Which is great for me, not so good for those selling!

Indeed. I was thinking it all coordinated rather well with the red flash of the underside of a pair of Louboutins rather than DMs. Not sure the budget will stretch that far once I've finished the house.

Fair point!

I bought a cheap microwave in Asda at the weekend for the site cabin. It had a tricky security tag, buried in the packing tape and the cashier's manicure was in mortal danger trying to remove it. You should have seen the look I got from the man behind me at the till when I refused his offer of a bunch of keys and instead got my Swiss army knife out and made short work of slicing out the tag.

For the 12 days from 2018-11-21 to 2018-12-03 the night usage was 417 units (82459 - 81988). That's equivalent to a steady 1.45 kW. That actually seems quite low to me.

How many are just the tube broken and how many is it the heat pipe as well? Heat pipe just pulls out the top. £15 for just the tube, £25 for tube and heat pipe on the Navitron site at the moment (for 47 mm tubes that yours look like, but I'm not sure).

Halfords batteries won't last a year in an off-grid home application, I'm afraid, as even their supposed "deep discharge" batteries have a really short cycle life, around 200 to 300 cycles is typical.. There are really only a couple of proven off-grid lead acid battery systems, and that's either to opt to fit Rolls wet batteries, as Paul Camilli uses, or to use forklift battery packs. Lots of off-grid people swear by fork lift packs, as they are often available at a reasonable price. The key to making them last seems to be to never run them below about 75% to 80% SoC, to always control the charge regime carefully to minimise gassing and to regularly keep them topped up. The need to never deeply discharge lead acid batteries, even fork lift or Rolls cells, means that the installed capacity has to be around five times the usable capacity. It's tough to get below about 5 kWh per day consumption when off grid, so that implies having around 25 kWh installed capacity as a bare minimum, more if you want to live with all modern comforts. A fork lift pack will anything from about 600 Ah to 1000 Ah at 48 V, so between 28.8 kWh and 48 kWh installed capacity, around 5.8 kWh to 9.6 kWh usable capacity, and cost somewhere between £2500 and £3500. With luck, and careful looking after, they should last ten years to fifteen years. One challenge with them is the weight and getting them to where you need to put them, as even the individual cells in a forklift pack are damned heavy to shift.

yes, thats an option. and I did think about getting them to the local sports centre for a shower there.

Not sure where this thread is heading. Home generated KwH are precious and costly to store, surely the OP should drop in an LPG tank for space and hot water heating. His off grid electrical requirement would then be scaled to the worse case winters day demand for all led lighting, TV, central heating pumps and white appliances which should not be a scary number. Drawing from memory on my boating knowledge... £3k for a 5KVH diesel generator, wet acid batteries 1000 12v amp hours for say 4KwH of usable capacity = £1400 from Halfords then round that off with a nice deluxe Victron invertor/charger for £1500. I know such a scratch design needs improvement but my intention is to show this problem can be solved when the alternative is a £40K grid hook up cost.

They are usually just a push fit into the manifold, often with a bit of thermal grease around the end of the heat pipe.

Yep, if you are good at DIY that's probably the way to go even if it means you don't get the RHI. If you're not it seems to come down to whether you can get someone do it, regardless of whether it's MCS or not. I have only managed to get a single quote (for 14.6k). That's RHI eligible. Even if that's the going rate I would like a second quote to validate this. No one here seems remotely interested in doing it.

I think that's pretty much all we did. The council agreed to the name and then everything else sort of happened. We did ours early like you in order to get deliveries to the proper address name rather than 'plot 2'. We even got bins delivered way before we were ever paying council tax here. They just asked that we didn't fill them up with building rubbish.

And if you want an example of persistence, that's one of the very best I have ever read. No matter how often I read it, it still makes my withers shrink - well disappear actually. I could not have been that hard core about finding a solution to a self-build problem.

Have a look at the contestable elements of the £40k quote and see if you can get it done for less. Also have a look at @JSHarris's experience with a borehole water supply - not always at all simple.

Substructure is all the parts of the building below ground. Unless you plan to leave the site as is for several years there will be no issue with freeze / thaw.

I just bought a cheap dirty water pump from Screwfix and as long as there is a bit of a sump it will empty it. Tip if / when it breaks within guarantee, SF will not ask for the old one back because it is "dirty" and just send a replacement.

Being able to use any excess pv I generate to heat the water up no matter what!!! ?

The only issue I have with that balcony is that you can only access it from the bedroom. You’re unlikely to then use it for entertainment, so it’s somewhere for you to have a coffee etc in the morning. That would mean that needs a couple of chairs and a table perhaps, which doesn’t need a balcony that size ... I would steal 2m from the balcony, move the entry door back so you come into a lobby/dressing area and then into the bedroom. That means anyone getting up at an odd time goes into the bathroom / dressing area only once and then out into the hallway and not via the bedroom. I’d also square that bathroom off - you can always have a sliding door into it, or create a “wet end” and a “dry end” to the bathroom.

As we are almost classed as a bog I bought a cheap “sump pump” on Ebay, yes they will not pump the last 50mm but when the trenches were dug we dug out a sump (200mm lower than trench bottom) about a foot square, adjacent to the trench, just make sure you remove the pump before filling with concrete?

One plus out of all this and I'm really struggling to find any is the missus's attitude to the stable block has changed. Whenever she complains of my tools lying about I get "You've got a double garage, a shed and the stable!" I've been saying for years stable is unfit structurally imo to store/work in & needs to be demolished and rebuilt. Her most recent idea was to put all the kids toys and keepsakes in lidded plastic boxes and store in the stable. When I said the (bowed, asbestos) roof leaks so badly and there's running water on the floor she said we could put a tarp over it. I gently suggested yesterday that had she stored everything there this wall would have come down on it all! As an aside she ventured into the bathroom the other day and remarked how quiet and draught free it was in comparison to the other rooms. I said "That's because I try and do it right!"

The problem is, that is the model I wanted. My original broad brush plan was to max out on PV and dump it into a SunAmp directly - it would seem this is no loader optimal for efficiency so an alternate course of action is required to work around this issue.

No, not at all, what on earth gave you that idea? This is getting to be just scaremongering now, and I think we should stick to facts, not wild speculation that is way off the mark. The current accelerated cycle testing programme has run to well over 35,000 cycles with barely any detectable degradation at all. Put into context, and assuming two cycles per day (which is pessimistic) then 35,000 cycles equates to a life of at least 48 years.

First off, I can't see Sunamp responding directly on here. Secondly, I'm not convinced there is anything underhand going on at all; having been dealing with them since 2015 I'm absolutely convinced that their focus is primarily on the technology, and sadly not product engineering now. That definitely wasn't always the case, though, the Sunamp PV was a very nicely engineered product, as I mentioned in this blog entry http://www.mayfly.eu/2015/10/part-forty-getting-into-hot-water-episode-two/ . My view is that the fairly simple control system that the current eHW product has is already known to be sub-optimal for the excess PV generation use case, but that they aren't so focussed on this model now, presumably for reasons to do with the largest market segment they currently have. Putting aside the case and top insulation design, which clearly needs some further work, the only identified operating issue is the inability to keep the eHW models topped up when charged from excess PV generation, as far as we know. I'm not aware of any issues with the other products in the range, so heating those from a boiler, ASHP etc should be fine. The difference between the models is that all except the eHW are primarily heated by hot water, very much like the original Sunamp PV. We have speculated, with some understanding of the probable issues surrounding the use of direct electric heating of the PCM, that the rational behind the eHW model having the selectable 90%/50% depleted charge acceptance threshold as being related to the use of a direct electric heating element embedded in the PCM, as it's only that one model that seems to have this limitation. This information is included in the installation manual supplied with the product, but was not available in any of the pre-purchase information that I read. Had it been made clear that the unit needed to be discharged to ~4.5 kWh remaining before it would accept any charge then I wouldn't have gone ahead with the change, as that's no better than the Sunamp PV I already had for our use case. A better option for us would have been to buy two more Sunamp PV heat cells to double the capacity of our old unit, whilst retaining the heated water charge system.

That is spanking small crushing Peter.

It was tongue in cheek. But I have often said it is a shame flourescents are so lamented as "old" and what a shame nobody has managed to make one that looks modern. Well that fitting you have shown would work equally with two flourescnet tubes and look modern.

At least they are making an effort to bring something to market that’s made in this country, from what I have read they are very good at replacing anything that’s wrong (lids) and hopefully with feed back will update their units and remove the gremlins.

Hi James, mine is 22mm caberdeck, 225 i joists @ 400mm centres, 100 rockwall between joists, 15 mm plasterboarded and skim. I think your EPS from wunda will help a fair bit, but might be worth sound plasterboard or double board or plasterboard on top hat rails (disconnects plasterboard from joists to stop sound. ) we had an embarrassing moment the other weekend, my mate had a bit too much to drink, his wife went to bed early (so us blokes could chew the fat!). And he was moaning to me about his wife. When he went to bed she was awake and told him she could hear every word he said. Breakfast was a bit chilly ?

Years ago a neighbour planted a row of conifers right up to the boundary between us. Needless to say they all 'died'.

I'm not at all fussed about having a SoC indicator, all I MUST have (and this is not at all negotiable) is the ability to charge the unit with excess PV generation whenever there is any spare heat storage capacity available. The present system is ludicrous, and significantly poorer in this regard than the old Sunamp PV we had. That would always accept excess PV charge if there was any spare capacity in the unit, not refuse to charge when there was still ~50% of the capacity sitting there uncharged. I may just as well have a 4.5 kWh heat store, as that's all I've got, in effect, if the damned thing refuses to charge from excess PV until it's 50% depleted. If I sound annoyed, it's because I am. Compared to the Sunamp PV the Sunamp UniQ eHW 9 is only using a fraction of our available excess PV generation, and instead it's costing us money to charge from the grid most of the time.

Crimewatch in the late 90’s kids tv in the 80’s...

Case adjourned due to serious accident on motorway .

I have tried submitting that form again. Only this time I did not tick the "new house in the last 12 months" box. I expect it will result in the same you have to pay the fee" response.