Leaderboard

Wow, we have finally started, and what a journey. The goal of the last 8 days was to try to make the the stars align. We had planned several meetings / connections deliveries all to happen the 1st week in April, and this was it, lets see what unfolds. Firstly, the plot, being located high up on the East coast in the highlands, which is basically a large un-serviced field has a few logistical issues, the main one being storage, the second distance. We had quotes for containers to be purchased and delivered in the region of 4.5K so alternatives were needed. The initial solution is the back of an Asda delivery waggon, 12ft long, 7ft wide,6ft high, with 3 lockable doors, and racking for the green trays, also a larger roller shutter section. £250 - with working fridge if required - (this may have a second life once were up and running with rare breed pigs🙈). just need to get it from Morecambe 430miles North. Secondly how to get everything to site. We bought an old removals wagon - 7.5Tonne ally box with tail lift. MOT till NOV 515,000KM - 1 careful owner Our hope was for this to get there in 1 piece, and be left on site as storage. the sum of £1200. all in with insurance (which may be cancelled) its has cost us £2K. Talking with my timber supplier, he warned me of impending price rises and possibility of shortages due to the unrest in the UKRAINE. so out of the blue I bought all the timber 450M of 6x2 C24, and 56 off 11mm OSB for the PODS. In addition to this I found a contact selling factory rejects of 120mm PIR insulation. In Scotland the pods need to achieve good U values, so 120mm on roof and in floors was required. Basically this guy buys pallets of insulation that are usually end of production run , or slightly damaged corners etc, and not full sheet sizes. I went to look, as he has had some bitumen coated and fibreglass coated boards. Generally the sheets are all 1200mm wide, min 600 long, most are around half board length, but will need to be trimmed to make them suitable for the warm roof. I did a deal to buy the equivalent of 44 Boards of 120mm some Bitumen coated, some fibreglass for the sum total of £660. This is a massive saving on 'Box Fresh' Now I had a problem, with the insulation tightly packed into the back of the truck and leaving some pockets to slide the timber in I had filled about 2/3rd of the truck, I didn't have room for all the timber or the other stuff I was taking. The revised plan was to cross our fingers and hope the truck will not only get to Scotland , but now return with a view of making another trip. Living accommodation. We found a static caravan, 2 bedroom in V good condition, delivered to site included in the price. The deal was done and he would get the van to site for our arrival on the Thursday, along with the delivery of our other investment an old Ford 550 Backhoe Loader, with buckets and pallet forks. We decided to set off Wednesday evening, with the plan to see where we got before we were too tired, then to sleep in the Wagon / Car. The picture below was us all loaded with 430Miles ahead. Me driving 'Nessie' as Mandy has called her, and Mandy Driving the Car / and trailer. I know we look like 'Travellers' but needs must, what will the new neighbours think when we turn up..... The Journey was horrendous. Setting off at 18.00 the trip was uneventful, with he exception of filling Nessie to the tune of £245 with diesel and not knowing how far these 150 litres will get us. Uneventful until we got to the A9 around Perth, then the snow started. Visibility was poor, and the local truckers seemed oblivious to it. Mandy had a big scare on a dual carriage way where she lost visibility of the edge of the road, and found herself nearly hitting the verge, a stab of the brakes and forgetting about the 16ft trailer saw said trailer try to over take her. Luckily she managed to correct this, and coming to a stop in the dark with snow on the dual carriageway, composed herself and set off again. At 03.30 on Thursday we pulled into a layby just after Inverness. Got our heads down for a couple of extremely cold hours (-4). and set off to the croft, arriving around 8.30.. During the drive we were informed the Static- our accommodation for the week was not going to make it - COVID... I managed to make a few calls and Borrowed a 3 berth Tourer from GOW Plant Hire / Groundworks in Caithness.. What a top bloke.... This is us on site day 1, digger arrived..... The Plot.. So down to it. Day 2 on site Friday. Electricity was to be connected on Wednesday 6th, we needed to dig a 30M Trench and install the cabinet / concrete base. This had to happen. Over to the digger to fire her up.... no go. Quickly the battery went flat. We moved Nessie closer, did a quick 30Mile round trip and bought some jump leads and by lunchtime and still no joy, turning over but not firing..... it was running the day before but they had to jump start as it had been sat in the yard for a few week. Ok looking at the battery it wasn't the correct one, so another 30mile round trip and the owner of a monster battery we tried again. no luck, I phoned a mate mechanic he advised trying spraying cold start into the air intake. ok another trip? , No, he told me to try deodorant as the propellant may well work, one quick spray and the old girl fired immediately. Best smelling digger in the highlands... Now to get to grip with an old backhoe, I've experience with up to 5 tonne 360 machines but never a back hoe, so this took a while to understand how to dig a straight trench next to a fence.. I managed to excavate the connection pit and around 15M of wandering trench by the end of the day. Day 3 Saturday It was cold and no amount of deodorant was working on the digger. The mighty battery was losing power... Time to try Nessie to give a boost, we got the Truck stuck in the mud... FFS. we needed the digger to move the truck, and the truck to help start the digger... This was a testing day, and I know from experience in building game you have days that just fight back, and this day was fighting hard. Mandy set off in search of some supplies and some cold start. By lunch she was back, I had made the shuttering for the cabinet base just needed the digger to get the concrete over to the hole. Cold start didn't work and we both felt deflated... Numerous attempts with planks, stone etc to free the truck were not working. As a last resort as the sun was now out and shining we gave the cold start another go and the digger jumped into life.. Obviously not a morning person... We moved the truck to relative safety of some drier ground with the aid of the digger and concreted in the cabinet. Another 10 M of trench, and we made a start exposing the water main. I noticed the digger was beginning to be sluggish and leaving hydraulic oil pools, when I check the level it was nearly empty. So Parked up the digger, next to the truck, batteries next to each other - just in case. We retired to the un heated caravan, and I went to the Generator to start it, we had a 2KW heater that helped take the chill off, A couple of pulls and the cord snapped😂. the day was going to round 12 like it or not. So tools out and repair underway. Day 4 Sunday. No Hydraulic oil till Monday so left the digger alone, and marked out the position of the pods, and the septic tank, I wanted to do some digging here to confirm the suspicion that the rock level was high, and some breaking out will be required. We hand dug a trial hole for the water main, as we found electricity cables running towards where the trench was going. We hit rock 300mm below ground, so were happy to dig this with the machine on Monday, We also started unloading the insulation and timber from the truck. We sandwiched timber and insulation with visqueen and ratchet straps to create a heavy mass that hopefully wont blow away whist were not there. Day 5 Monday. With Hydraulic oil on board and the shelter of the truck the digger fired first thing, and we were off. Mandy continued un loading insulation. We dug a small trench for the water (we new the main was laid in a blasted trench to a depth of 800mm) we had to breakout our trench with a 110V Breaker to obtain the 600mm depth and hand dig to expose the water main, I left Mandy to this while I dug the septic tank hole, I got to a depth of around 800mm before I hit the rock. This will need pecking out now. We installed a homemade standpipe, and blue pipe, then asked for a track inspection via the online portal. We were given date of 11/12/13April, but we put a note on to say we were on site until the 8th. They responded and the Meeting was set for Wednesday 6th - result. Day 6 Tuesday - the night was very windy and wet. A cold and wet start, We finished off the electrical trench, laid the ducting / draw cord and all was set for connection the next day. Made a start on the pods foundation dig. Day 7 Wednesday - electrical trench was full of water, and the ducting was floating. the heavy rain drains towards the sea, and thus straight into this trench, I was concerned that the Install may be called off. SSE turned up around 10.00 and were not bothered in the slightest. They connected a new length of 95mm Wavecon to the pole and jointed the existing 2 houses and our new supply - 2 core 35mm straight concentric to this 95mm cable. Resin pour joint box, and fitted the 100A cut out in the cabinet. They were done in 2 hours. left me to throw the cable in when the resin had gone off. Scottish water inspected the trench, and this has been signed off and will be added to the works list, hopefully a few weeks. I filled in the cable trench, We managed to rough dig out the pod foundations and found the rock is close to the surface. so the slab foundation will be pretty much mass fill concrete around the perimeter, with some MOT to reduce the thickness to 4" for the slab. This will then have a Radon barrier on top and a floating floor insulation on that, Due to the poor living conditions and more rain and wind we made the decision to leave Thursday morning. Day 8 Thursday, We packed up the caravan and Nessie then dragged the caravan out of the mud with the digger. The trailer was also dragged clear with the digger, but Nessie was so at home she didn't want to leave. I was pushing here through the mud, but she was sinking. Fortunately tour Farmer neighbour saw our plight and came along with his massive tractor and dragged her clear. We left site battered, bruised but happy in the knowledge that no matter what was thrown at us, we had achieved what was required and more to boot. Thanks for reading... its all possible, Mandy made a few videos if you want to see them https://www.facebook.com/The-Windy-Roost-101816829105927, you can follow the progress there as well...

As promised a little update on the Battery Storage. Firstly i'm very glad I bought when I did, as everything battery storage wise has skyrocketed in price since, even the prospect of adding a US2000C seems unlikely for now, though to be honest, going on my usage I don't think it would add a great deal of benefit. So I'm running the Solis 5th Generation AC Coupled Inverter, which does have a couple of niggles, which at present are reducing its savings potential. Those issues are: Whenever the battery isn't at 100% SOC, it pulls an amount of power from the grid, somewhere between 60W and 100W Even when the battery is actively charging, it still pulls the same 60-100W from the grid, regardless if there is enough PV power to charge the battery and cover loads at the same time. Once the battery is 100% SOC and im generating PV more than my load, I import 0W. Pulsating loads (such as induction hob) the unit can find hard to track, due to their pulsing nature, and the delay in reading the CT clamp and acting upon it. Now my base load is around 45W, so that means that since i've had the battery, i'm actually consuming more during the nighttime than i did previously, which is a negative. I got in touch with Solis UK Support about this issue, and they say they are aware of it, and are going to be adding 2 offset values which will be user configurable to combat this problem, and they've told me it will be available in around 2 weeks time, so we shall see. So although it will be a static value, i should be able to get much nearer to 0W import from grid whilst ever there is charge in the battery, but its not at 100%, and its not over its maximum demand (around 1.8kW). To better news, aside from the issues above which should get resolved, the system is essentially running off grid now, and has been since the middle to end of february, pretty much every day without fail, just with the odd bit of import for things like kettle and oven, to cover above the 1.8kW if the Solar isn't generating enough at the time, which is getting an ever smaller occurence. So the graph above is from March, with the Red bits on the top graph being the bits of import. The bit at the top showing 22kWh import, the majority of this was during the early february days after install when solar PV wasn't doing an awful lot. As you can see I'm still exporting ample amounts to the grid also, not that it would make any difference at this stage. Until I get the full years amount, its almost impossible to say how much this will have reduced by. Today I've done a load of washing and then dried it in the heat pump dryer, and following that I ran the oven on its Pyro clean cycle, and come tea time, i'll be fully charged again and ready for the evening (Thai Curry if you were wondering!). This one I'm keeping an eye on, obviously we know that these inverters will never be 100% efficient, but from those figures i've sent 177kWh to the battery, and only been able to get 124kWh back out again. Some of this will be down to the BMS consuming power to keep the battery healthy. So the inverter is 94.0% efficient at charging (100kWh sent to the battery will yield 94kWh of charge in the battery), and 94.5% efficient at discharging (1kWh being discharged from the battery will yield 945Wh). Please correct me if my maths is off! Entirely possible as I've got the plague at the moment! For how much its changed my import amounts, another tricky one which will have to wait for the end of this month, or maybe even next. I didn't get the smart meter installed til the end of March last year, but as a comparison: March 2021 (18th to 31st) - Imported 46.9kWh March 2022 (1st to 31st) - Imported 48.3kWh And this will drop further with the firmware upgrade. Will keep you posted in another couple of months time!

I don't think you'll generate enough to effectively charge the batteries, except for peak days in summer. Once you bear in mind that you won't generate the full 2kw due to the orientation, and that your day to day background load will each up another couple hundred Watts at any one time, then you're left with very little. Better option is to change your electric use habits (washing machine and dishwasher on time delays, solar diverter to heat hot water etc) to make the most of the daytime generation. And if you end up with an electric car in the future, then that will eat up the lot. Don't forget that you'll need oprimisers on the panels to maximise generation. Can reccomend the solaredge optimisers and inverter setup. That first roof looks big enough for 4 panels in landscape 2+2 configuration. Have you considered that? Remember, you can run the GSE trays right to the gutter and half a slate from the verge.

What you can do, is set the timers on the heating system so the ASHP does not turn on to heat DHW until 11AM. By then solar PV production should be good, so it is likely the ASHP will be using up a good chunk of your solar generation. It's about the best you can do, other than (if you are in all day) manually turning on the ASHP when the sun comes out. That, and shifting all the big appliances to the middle of the day and the immersion diverter means I don't export much of my PV.

No. For the simple reason your heatpump will have a min draw of something like 1.5kW. Your excess PV generation could be something as low as 200W... Which would mean if your heat pump is on, it'll be drawing much more power from the grid, negating any COP advantage over a immersion coil. The solar diverter will control the power to the immersion to match the excess generation, and can do this from a few Watts up to 3kW. We'll be setting our heatpump if for cooling and time for during the peak afternoon... So if cooling is needed in theory most of the power will come from the 4.5kW array, and only some from the grid. At this time of year we're not producing enough to power the heatpump, so still on the immersion

Did anyone else read this article dated 12 March? Essentially, a couple moved into their not quite completed self build in 2015 & made a VAT reclaim within the usual 3 months of receiving their 1st council tax bill. The VAT was repaid. In 2019 they submitted a 2nd claim which included construction of internal walls, kitchen & bathrooms. Unsurprisingly HMRC refused this claim - as we all know, you're only allowed 1 claim. The couple appealed on the grounds that being allowed only 1 claim was unreasonable as many self builds take years to finish. The judge at the first-tier tax tribunal allowed their appeal & granted permission to make a 2nd claim once the house is complete. HMRC did not appeal but said it was an unique case - not something I would agree with! Anyway, it seems like some kind of precedent (just my opinion as I have no legal training).

I was talking about corrugated cardboard. Seriously, it has a reported R-Value similar to other common insulation materials: Typical R-values Material RSI-value (m2·K/W) R-value (ft2·°F·h/BTU) Icynene spray 0.63 3.6 Open-cell polyurethane spray foam 0.63 3.6 Cardboard 0.52–0.7 3–4 Rock and slag wool batts 0.52–0.68 3–3.85 To avoid convection on a vertical surface, you would align the flutes horizontally. Insulation is primarily a matter of trapping air (one of the lowest thermal conductors) in an envelope with low thermal conduction/contact surface area. Fluted cardboard sheet meets these requirements. The downside is that it is not as robust as mineral wool of the other cellulose products. But sandwiched between ply sheeting it should perform equally well - provided it has a vapor control layer to prevent condensation forming on the cold side.

No it’s to narrow

A good vapour membrane stapled and pinched between SC battons and Rafters would be quite capable. I reckon if you were careful you could lie on it yourself! We have 400mm Above ours and it's fine. They regularly use netting in the US which looks infinitely more flimsy. I think @Nickfromwales has some cellulose contacts from memory.

Comes down to marginal losses and gains. Heating a DHW cylinder or a buffer tank us cheap and easy. And for 8 months if the year, will probably supply 80% if your needs.

A1 reverend. 😎. I’d be priming the surfaces but you don’t want the PVA, so use tile adhesive primer or SBR maybe. Foam will adhere to what is behind, if that’s friable then it’ll be shart.

Yes a precedent cannot be set for a tribunal case and HMRC may choose to ignore the outcome. The tribunal judges do generally look at previous cases however and often quote them in their decision reasoning. That said judges can rule as they see fit having interpreted the law so it often depends on interpretation. HMRC can say whatever they like on a claim form or verbally but if their ‘guidance’ does not correspond to the legal position then it’s not valid. The tribunal will only make a judgment based on what is lawful although tribunals have been known to criticise HMRC quite heavily.

A Shelly could do it easily with a temperature add on. You can do the if/then logic also.

My friend did the same with a fibre laser... much cheaper from China and all built with branded parts. Part of the attraction to move away from gas is to remove the requirement for me to get somebody with a gas safe cert to service the appliance. I can touch every other bit of plumbing in the house, so adding the heat pump into that list would be beneficial from a servicing point of view.

Sorry, wasn't trying to be cocky using the acronym. More here: https://www.electrium.co.uk/about/news/5-things-you-need-to-know-about-amendment-2-18th-edition

This is the crux of all heating systems. Old night storage heaters work well, if sized right and used correctly. Open fires can heat a place as well. Crap efficiency though.

This is slightly misleading. Better to say ..."any 15kW heat source, matched with appropriately sized emitters, will heat it." You can't replace a 15kW boiler with a 15kW ASHP and expect to get the same output without also checking the rads can still deliver the heat demand from the potentially much lower flow temp.

In Canada when they design heat pump systems they don’t aim for 100% heating requirement but leave a few of the coldest days each year slightly short on heat as the capital cost outweighs the benefit and some direct electric heating is used to top up on those days

Sorry to be the bearer of bad news, but as I feared the 0% only applies to supply and fit. Sales of equipment only will still be 20% VAT https://www.bimblesolar.com/budget22 More jobs for the boys. They don't really want us to install green energy products. Don't shoot the messenger.

If you want to do it for environmental reasons then I'd read up on the best way to set up and control heat pumps. As you won't be there to play around with the settings you want to get it right first time. There are good arguments for not using an internal thermostat so you want to make an informed decision. You should also find a reliable company to do your system design. It isn't as simple as removing the boiler and putting in a heat pump. The company should do heat loss calculations to work out radiator sizes and heat pump size. They will also tell you if any of your pipework will need changing. As I said, I like our heat pump but it isn't a simple task to replace a gas boiler with one.

Heat pumps are most efficient at lower delta T’s lower difference between source and delivery temperature. So to get to 50C efficiency is not so good. most likely an immersion will be incorporated to raise temperature the last bit. I want one but can’t find one small or cheap enough.