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https://www.pv-magazine.com/2023/01/02/residential-thermo-acoustic-heat-pump-produces-water-up-to-80-c/ French startup unveils new residential thermo-acoustic heat pump French startup Equium has developed a heat pump core that works on acoustic waves and produces hot and cold air. Equium manufactures the core and works with another company that integrates it into heat pump systems. The units are scalable from 1 kW to 3 kW and are designed for residential applications. The novel heat pump can purportedly reach higher temperatures than existing heat pumps, without the need for refrigerants. It works with a high-fidelity (Hi-Fi) speaker powered by electricity that creates an acoustic wave in a closed-pressure vessel filled with helium. The acoustic wave causes the gas to compress or expand, displacing heat from a lower temperature to a higher temperature, or vice versa. The heat pump core is filled with water, which absorbs or releases that heat. “The acoustic wave does the work of compression and expansion of the gas that produces heat or cold, respectively,” Philippe Loyer, a product manager at Equium, told pv magazine. Loyer said the heat pump can generate domestic water at up to 80 C. He claims that one of the key benefits of the acoustic heat pump, in comparison with traditional units using refrigerants, is its ability to reach very high or low temperatures. “Traditional heat pumps use refrigerants with a temperature phase. They a have temperature limit, which is the temperature of the changing phase from liquid to gas of the refrigerant,” said Loyer. “In our core, the helium stays in gas form. Because helium remains a gas until -300 C, we can achieve higher temperatures inside our heat pump core.” The heat pump purportedly works with all external heat sources, including air sources from -15 C to 50 C. Given that its core is filled with water, it works best as a water-source and geothermal heat pump. To be used as an air-source heat pump, the unit can be equipped with a fan that transfers the heat from the air to the water, according to Loyer. The heat pump has a coefficient of performance (COP) of three to four, which means that it produces 3 kW to 4 kW of heat for each kilowatt of power it consumes. Equium is targeting 8 kW to 10 kW of thermal power for its heat pump core, Loyer said. It has a 30-year lifetime, with an easy installation process. The acoustic heat pump also offers better modulation than traditional units. “We have the same efficiency as traditional heat pumps, but we have better modulation thanks to acoustic transfer,” said Loyer. Traditional fixed-output units cycle between on and off multiple times a day, switching between zero and maximum capacity to achieve the right temperature balance. But the new heat pump modulates its output to continuously provide the desired temperature. “The output regulation of a classical heat pump is very energy consuming. On our acoustic system, the regulation is very easy,” Loyer explained. “If you want less power, you can just decrease the volume of the Hi-Fi speaker, to 10 decibels (dB), 20 dB, or 30 dB for example.” Equium claims that the heat pump system is completely silent, despite the use of a speaker to generate the acoustic wave. The level of noise is reportedly lower than 30 dB – the equivalent of a whisper. “The sound our system produces stays confined inside the core, so you cannot hear it from outside,” said Loyer. Equium is now conducting field tests for its thermos-acoustic heat pump. It expects to launch it in the second half of 2023.

Ah, months of storage. Not going to happen at a reasonable cost I'm afraid. @tonyshouse did a borehole to dump excess solar thermal I think. Not sure of the most recent results. Scanhome and University of Ulster did a project. A year in the life of a passive house with solar energy store V0.9 (energyexpertise.net) Whilst it was successful it was expensive. Stored heat was 0.79€/kWh.

Ok, that crossed my mind. Re hydrostatic loads. There are a lot of basements in the country. Many are damp, but few have water gushing up. Most don't have reinforced concrete, but you do. . So intuitively I think you are over-worrying. The SE may be happy to help on this, esp as you won't be claiming against them. What method is used for the tanking? Does it enclose the courtyard? I might be a cheaper job than the pumping station you are looking at.

Would need to be careful you did make a bomb, not sure of the expansion rate, but a temp rise of 450 degs, could give a big pressure rise in a contained volume of gas.

I sent the above pictures to valuation office and was told the bungalow did not qualify to be deleted for council tax. I eventually got valuation officer to visit, he took one quick look around and deleted the Bungalow from the purchase date!

Good for the sole to help out. My thoughts are: That extension is quite long 6.0m and will pick up a bit of wind on the long sides thus you need to stop it moving sideways in the plane of the main rear elevation of the existing house. You starting point here is to ask.. can we transfer all the sideways wind load to the existing building and how do we do that.. and is the existing building able to take the extra sideways loads. It looks like a terraced house. One commonly accepted principle is that if you live in a terrace your house has to take it's "share" of the load. In other words you can't shed load onto your neighbours.. because if everyone starts doing it you can destabalise the whole terrace of houses. The back door introduces a significant break in the load path, that is an anomoly particularly as it is next to a pier which will probably be carrying quite a lot of load from the main roof.. it will protest if you try and use it to hold an extension still. My initilal thoughts looking at the geometry is that you'll need a goal post (steel portal frame) along the front elevation of the extension. If it only extended some 3.5m from the house then you may get away with that masonry return on one side. I would recommend that you speak to an SE.

BiPVco have some products that can stick directly to a standing seam roof https://bipvco.com/ They've been discussed here a few times, most recently: Alternately, there are clamps and kits from S-5 that allow for standard panels to be fixed directly to the roof, without the need for a frame: https://www.claddingmate.com/products/s5-e-standard-clamp I've not come across integrated trays for standing seam roofs as there are for slate and tiled roofs.

Maximum wall length covered by Part A rules is 12m. Although usually you start to break the rules (due to multiple openings etc) when you go over around 6m. No a lintel won't provide lateral stability. Walls are panel structures and panels need linear supports else they will span in two directions. For masonry this rarely works. A lintel will only support it at a 'point' (in the top corner). The difference looks a bit like this: Orange zone being at risk. I'm afraid we're into the realm of 'step 1: attend university and do a civil engineering degree' but fundamentally, the layout proposed does need a windpost. Best person to speak to next is an engineer who can specify what you need. Potentially a windpost manufacturer would do the calculation for you as well. What I would do is put a windpost at point 'W' and make the studwork wall a shear wall a point 'S' (this would be an extra layer of OSB and some additional strapping to the wall and the floor). Edit - actually what are the red blobs? Are they the proposed windposts or something else?

Perhaps limits on high frequency field strength force the switch? Can't crank up the frequency because fail field strength >90 kHz? https://www.aceee.org/files/proceedings/2014/data/papers/9-702.pdf http://www.emfservices.co.nz/resources/emf-measurement-examples/induction-cooktop This one seems to say it's flicker EMC vs the milk and supports ~3 sec cycles: https://www.infineon.com/dgdl/Infineon-AN2014_01_Reverse_Conducting_IGBT-ApplicationNotes-v03_01-EN.pdf?fileId=db3a30434441da19014445a1e7560135 "The minimum operation frequency of the burst mode has to be set high enough to avoid any non-uniformities of heat distribution in the vessel, and at the same time to avoid noticeable fluctuactions of the temperature in the food, which would end in unefficient cooking processes. On the other hand, the maximum operating frequency is usually limited by the EMC requirements. Usually, a burst frequency of 0.2-0.3 Hz is used." Clashing frequencies explain some of the squeaky harmonics with multiple pots on the go too. Deliciously complicated things are these!

If you're trying to store heat, no reason to use PV - solar thermal captures about 3x the energy per unit area, and you're going to need a liquid system to get the heat out again. It's been done a few times (search for "Sonnenhaus" or "domestic interseasonal thermal storage"), but it's hard to make a success of it. A lot of the issue is that unless you have an exceptionally well-insulated house you're going to need a lot of heat capacity in whatever you use for storage which adds cost, and it needs to be thermally segregated from the house to avoid overheating as well as keep the store hot. You end up more or less building the house around the thermal store, with the associated costs and compromises. The problem is really that if you are willing to design a house around minimising energy drawn from the grid, you're always going to go for a Passivhaus-esque approach to reduce demand. Once you do that, not only do you not need very much heat but overheating starts to become a significant challenge if you're storing a lot of heat energy inside the house. If you go for the heat pump + PV approach, you can buy an awful lot of PV + battery storage for the cost of building a giant thermal store into your design - and the amount you draw from the grid will be pretty minimal, with the PV helping to cover plug loads too. If I'm understanding you correctly you've got 2 MWh of PV exported to grid over the course of a year (mostly summer?), and are looking to use that for winter heat given an available 4m3 storage volume. Sunamp are about the best you can do here - they're a phase change system (hence very energy dense), in industrial production and extremely well insulated. That could probably store somewhat over 250 kWh in the space you have available, with a standing loss of a few hundred watts - similar to a badly insulated hot water tank and thus probably acceptable. They also sell a large system which is probably suitable - https://sunamp.com/en-gb/products/central-bank-mini/#features . Having said all that, I can't see any way of doing this cost-effectively - you aren't saving a huge amount of energy over the course of a year, and even at current energy prices that really doesn't come anywhere near to justifying the investment needed. You'd make far bigger savings investing elsewhere, either in the house or maybe in something like Ripple shares.

Right, rather than trying to store energy at elevated temperatures, for months why not just use a heat pump. Then all you need to work out is the power needed to run it, and your potential to generate that power. PVGIS will be your friend here.

Any wall panel which complies with Part A rules is fine and won't need additional windpost/justification. Anything that doesn't comply will need a structural engineer's input to satisfy BC. I've rarely ever made a (non-Part A compliant) wall panel work without putting in a windpost or reinforcement. Windposts are a bit pricey but fundamentally are just a steel section with a bolt top and bottom. Left hand side appears fine to me. Only 6m long and at the bottom corner the two walls buttress each other. House construction is all about building boxes!

Most of the Architects are pretty tuned in to what BC will ask for It just saves time to get in there first

All this talk of using sand as a heat store and accompanying calcs is really getting down to the nitty gritty...

Specific heat capacity

I can’t see any dimension of the return wall but I would say there is an argument that WP’s are not necessary on that side. You will need a SE anyway so see what they come up with.

Rather than look at how much energy can be stored, look at how much energy will be lost, and how much insulation is needed to reduce those losses. Also look up Newtons Law of Cooling.

is that in the same way you did when ordering walk on glazing?

Usually just a switch.

Here's one prepared earlier https://www.caldera.co.uk/

Use Helium. It's specific heat capacity is over 5000 🙂 It's volumetric density might be an issue.

Fabric heat loss is dealt with by insulation / doors & windows etc, and ventilation heat loss is dealt with by arresting a) infiltration ( drafts ) and b) convection heat loss; loads of house builders / frame suppliers seem to not give this their full attention when detailing this at the roof level forgetting that heat rises . If you have poor ventilation heat loss measures ( eg not going to a very good / excellent ( not just 'good' )) level of airtightness, then all the insulation in the world will amount to zilch tbh as the saved heat will just escape to the clouds, whilst pulling lots of fresh, damp and cold air back in to replace it 'Excellent' airtightness will mean you could install lesser amounts of insulation ( eg build to our current and shitty building regs equivalent ) and you'll still have a very high-performance dwelling as a result. I would focus all my energy and efforts in the pursuit of the best AT score you can get you mits on, and once you are already 'in to' the installation of AT tapes and membranes, it will ONLY need you keeping a close eye on attention to detail and no stone being left unturned to take you to the 'excellent' result. Do not dismiss the value of putting in just a little more effort with this, as, if you're staying in the house long-term, the rewards ( lower running costs and personal comfort ) will be significant. You absolutely need a definitive statement regarding method of execution / target ACH score etc ( before parting with any money ) as a lot of lesser interested TF suppliers pay this lip-service only, and that's on a good day...... Ask for details for sections where tapes / membranes start / finish etc and what happens at wall / slab junction plus doors and windows etc. If they start squirming, it's time to move on to another frame supplier.

Throwing it out there.....could you use a literal vacuum as insulation. One big welded tank inside another?

Is a ‘ tube float ‘ the tube with basically a ping pong ball in it ? These I found stick ! Given your situation I would leave current pump as is . Add a new 50mm pipe ( for another pump ) break out that pump recess so it’s larger . You can then have 2 pumps work in parallel each with an outlet ( 32mm and 50mm ) . If in doubt double up .

Depends on the pressure. The SHC is better than sand at 1kJ/kg.K. A m³ at sea level has a density of about 1.2 kg/m². Double the pressure, halve the volume.

A very interesting project. How much space do you have to play with and how much excess energy do you have to use? Is this a budgeted project with a payback window or a fun experiment?. In commercial systems they're claiming about 50% round trip efficiency and storage temps of up to 500 deg C.

Lots of Thermos flasks. Aerogel is 0.013 W/m.K

Make it a basic cube and then use vacuum panels for insulation.

For extracting heat, you could use an air to water heat exchanger, such as a car intercooler to allow hot air to exchange to hot water and then feed into house.

You could compress air, which will warm up with entropy and then add in extra energy with an element. Then release it back.

1 kWh. How are you going to insulate at those temperatures? How are you going to get the energy back out?

My slab out the rear does indeed has a fall and funnels water towards the pump. I do have then level pedestals ontop. It might be possible to put a concrete 'topper' with fall on your patio slab. Or ( depending on layout ) simply break a channel in it so water equally runs towards pump.

It wasn't built. The Home Secretary called it in and said the impact on a nearby village would be too great.

Your drawing showed it laid to falls towards the sump and a channel. If it is just a flat (ish) slab you would need to build some falls towards the sump before you use the adjustable pedestals and slabs.

I have thought about this as we have this same solution on our balcony but my concern is that the slab underneath is not level and so the water that goes through between the patio slabs will just pool under the patio. if I were to use pedestals then I'd need to get the slab to fall towards the sump first so that it and the patio all drain their surface water in to the slab. maybe there is a solution that I'm unaware of though!

I will need to read up both on Tigo and on my current inverter! The latter supports two strings, but has two inputs for each string, im not sure how these relate (probably just wired directly together internally). The current array is anyway split 1.5kW/2.5kW so I think its might well work simply to add to the new panels (with optimisers) to the shorter string. First step it to check that the SunnyBoy is happy if the maximum available power exceeds the spec, even though the voltage and current do not. I'm struggling to imagine it would do anything other than operate slightly sub optimally under these conditions to throttle back, but Id better check before getting too excited.

The 345cm end wall isn't a buttressing wall - doors and windows are not structural components. It sometimes is possible to deign a masonry wall to span top to bottom, but this has much less lateral capacity and requires a lot of fiddly detailing. much more robust is to use a windpost. The building regulations are a bit out of date on minimum return length. A wall with a cavity o 75mm needs 665mm. But many walls now have cavities of 100mm+ - this really needs a return of 780mm. That's fine until the beast from the east MkII rolls through, blowing over the fences. Structural design for domestic houses needs to consider a 50 - 60 year time span. In summary: Am I thinking in the right direction? Yes Do you think windposts will be required if the minimum returns and P2 are not met? Yes Is there a rule of thumb to when windposts are required? Masonry panels require support to be able to resist lateral loads. Most common is buttress wall in accordance with Part A. Designed solutions almost always require a windpost. Does the 3.45m wall works as a buttressing wall for the other two side walls? No What are the calcs needed to justify not using windposts? (e.g. Masonry wall panel design to EN1996?) EN1996 would suffice but it is unlikely to work without a windpost anyway.

Your Architect is probably prompting what BC will as for Wind posts are incredibly easy to install We had a similar extension on our last home I intended putting WPs in But our engineer designed an elaborate steel plate system bolted to the house I go with your Architects suggestion

Made a new bottom cover for my lad's 3D printer from an old oil drum lid. Left over from when I made an incinerator: Oven baked, VHT paint:

The architect has probably suggested windposts due to the lack of buttressing by appropriate return walls. I don’t think the end wall qualifies as a buttress even assuming there is a lintel and masonry above the door, it won’t give the same stiffness as a full height wall. Normally they would say windposts or buttressing ‘to be confirmed by structural engineer’. Have the drawings been submitted to building control for approval yet?

Burn stuff, fire good.

I think it is a realistic budget @Amateur bobbased upon my build allowing for fact that prices have risen post covid. And assuming you’re not talking about lavish fittings etc. The likes of https://www.dan-wood.co.uk you are paying about £270k for a house that size but that’s excluding foundations infrastructure circa £30k and kitchen (£5k plus), but of course is an imported turn key product which is inevitably more expensive than what you want to do. The planners direction to build a rural barn style build is definitely in your favour budget wise as has been mentioned a few times, as they’re directing you to build something that is actually cheaper to build design wise. Building with natural stone is time consuming and thus more expensive. My suggestion would be to keep you under or at budget is to come up with a 1.5 simple barn shape. Stick with render and timber cladding with a dash of local stonework at low height. Some of those links I previously provided show barn style houses have done that. Look at either steel roof or slate. I doubt very much planners would be keen on concrete roof tiles. Avoid a design that would involve steelwork and build with a timber frame. Make sure you put prioritise your budget to the likes of structure, material, insulation etc good doors & window. Don’t budget for the likes of metal switches and sockets budget for plastic and a simple inexpensive kitchen idea. If you do well with the budget for the important things then the luxury items eg sockets expensive kitchen can also be selected/upgraded at that point, or if necessary at a later date. If you are going to self manage the trades make sure the build is architect supervised, this provides a lot of protection if something terrible goes wrong and allows you to get a residential mortgage. If you don’t have trades experience yourself a simple saving is doing the painting yourself. Or fitting a kitchen which is a pretty straightforward especially if you have a simple design. Or labouring.

I cannot think of a reason to reinvent the wheel here tbh, and as long as there is a thermal break ( with one course of aerated ) then you're as good as it needs to be afic. Is this in motion yet / or still a blank canvass?

No. I don't see why you think you are responsible. Or maybe I do. The Architect has chosen to build a basement, extending outdoors. It should be completely waterproof from below and the sides.. Presumably (please!) the walls and foundation are designed to keep water out, as a basement with completely integrated waterproof structure (like a swimming pool o reservoir, but inside out. Then the SE has made it work structurally. Then someone has decided to dewater the flooded tank using a pump, of another's choosing. I dont think so..Perhaps the reality is that they didn't think it through and thought that the pump is needed to dewater the patio, not the whole site. And didn't think of the water getting in through the patio doors. Back to basics.: this should not need a big pump, which by default is dewatering the entire area, except to take out direct rainwater landing in the patio. This could have been achieved if the sump was also sealed below*, and only the water from rain landing in the patio area. If I was a cynical person, I'd be thinking that the architect has told you it is your problem, not their responsibility. Hence you are going along with it, spending more and perhaps not resolving the fundamental design error. I won't nag any more, as perhaps there are other reasons we don't know about. You seem determined not to trouble your designers, and to take all the cost and disturbance yourself. And perhaps have an unsellable house. This can be sorted by someone else if you want. To me the design is wrong, it is the architect's responsibility and they should sort it. I would write to them, and also the SE if they were engaged by you rather the Architect. AND I would ask my insurer (and /or mortgager) to look into it as a claim....They have the resources and clout to get this sorted at someone else's expense. btw I showed your sketch to my wife, an accountant. She said immediately that the design was wrong and the designer should resolve. The easy solution may be this * .Break out sump, and rebuild with integrated waterproof barrier beneath, fully linked to the house tanking. divert the land drains away from the patio....whoever's idea was that?

if the TF company wish to specify an airtightness target then I would suggest you negotiate a maximum result of 2ACH and no minimum. for them to state a range between 1.5 - 3 means that they probably won't try very hard to get to the 1.5 level but if you specify a max of 2ACH then they have to achieve that and, in doing so, will probably end up at a much lower than 2ACH level. there is a spreadsheet on here that @Jeremy Harris created that will allow you to see the potential benefit of reducing your airtightness and also increasing U-values. as @Iceverge says, airtightness has a massive effect on energy usage and insulation has diminishing returns.

Exactly the converse. If you are aiming for a minimum cost house you may be able to spare extra insulation and 3G windows if you achieve excellent airtightness. Airtightness is the single cheapest and best thing you can do to reduce bills and improve comfort. Passivhaus is 0.6ACH and probably the best standard although many on here have beaten that by quite a margin. Good design and about €900 of tape and membrane got us to 0.31ACH. The execution took thought however.

I'm with Octopus in Scotland and (finally) got 3phase smart meter installed after 6 months of trying with succession of b*lls-ups along the way. Just waiting now to see if it connects properly!

Most conveyancers are barely competent at advising on conveyancing. Wouldn’t ask them about anything else. Ultimately, although many aspects of the rules vary council to council, there are rules which apply nationwide, regardless of where you live. This is from gov.uk, it applies nationwide, even in Rushcliffe: If your property’s derelict Your property’s only considered derelict if it: is not possible to live in it, for example because it’s been damaged by weather, rot or vandalism would need major structural works to make it ‘wind and watertight’ again You can challenge your Council Tax band if you think a derelict property should be removed from the Council Tax valuation list. So I think you should challenge the council and claim that it should have been removed from the valuation list for the time it was uninhabitable as a result of being derelict.

I just noticed that there's a good way to measure actual overall U factor / energy/degree day described here: https://forum.buildhub.org.uk/blogs/entry/965-update-on-energy-use-based-on-4-years-of-actuals/?tab=comments#comment-6148 See TerryE's post where he uses a regression of daily energy used vs. external temperature: Returning to the data, the strongest trend is shown by the external temp vs daily total power use scatter plot, which fits to P = 60 - 2.45T, that is each drop of 1 °C in average daily outside temperature requires an extra 2.45 kWh heating. I also checked this against my pre-build design calcs which predicted 1.92 kWh, i.e. the as-built house performs about 25-30% worse than as-designed.