NailBiter

You might be lucky and have the setting already enabled (try connecting to it) but if it isn't you are going to need to pop the cover off and plug in an RS485. That will also give you access to some things that aren't possible via the Modbus TCP connection like writing meter data (even more stuff to break!) SolarEdge added some of their StorEdge controls to their client facing web interface but I've not used it. It would be worth checking around on Github to see if anyone has wrapped these for Home Assistant. It wouldn't give you the local only control you require but it might be harder to break things. You can either use the Modbus integration in read only mode (safest) or to control your battery (far more experimental) by turning on the power registers: https://github.com/WillCodeForCats/solaredge-modbus-multi/wiki/Power-Control-Options-‐-Configuration The only way I know if to backup your settings would be to screenshot all of the settings from the Home Assistant SolarEdge Modbus Integration page and to manually set them back if you have a problem. Might be worth screenshotting everything on the client facing web UI page too. I believe the client facing web UI would override the setting changes you make to the inverter but I'm not sure on that. Be very very careful, you can cause big issues and get yourself in a lot of trouble. You can also do cool things and have a lot of fun. Check twice, click once!

Thanks for taking the time to reply. Maybe ICF with a membrane would solve this issue: https://www.nudura.com/products/tremco-nudura-products/below-grade-waterproofing/ Looks like a very interesting place cheers. Nothing on their website about it though. I'll try emailing them if not but do you know where you read / saw this? There is another project detailed here (Howe Dell Primary School) : https://earthbound.report/2024/01/10/what-is-inter-seasonal-heat-storage/ I will check this out thanks a lot.

No additional hardware required if you have SetApp access (or can convince your installer to change a setting). You can follow the instructions here: https://github.com/WillCodeForCats/solaredge-modbus-multi/wiki/Configuration#enabling-modbustcp If for any reason you can't convince your installer to change that setting you can pop the cover off (make sure to properly de-energise your system first!) There will be two RS485 ports in front of you. One or other might be in use but they probably aren't if you are using their Zigbee system. Use one that is free and plug it into a Raspberry Pi Zero with a USB RS485 adapter (few quid on Amazon) it is only a pair of wires (A and B) and a ground. You can use a Modbus TCP Gateway if you prefer. The end goal is to get a TCP Modbus Connection that the above Project can access, doesn't really matter which way you go about it.

Yeah it's a few bolts to get the cover off and then the two RS485 interfaces are in the centre towards the bottom. Nothing the majority of people can't handle. That said you might not need to as SolarEdge now present their Modbus interface on the LAN too so you can just connect via TCP. Hit me up if you get stuck / have any specific questions.

I'd be very interested in hearing from anyone with a GSHP that charges it with heat in the summer for use in the winter. I know that happens naturally but you need a massive array which cannot be built over in any way (nor can it be fouled by tree roots etc).

Has anyone managed to pull this off? How did you do it? "Seasonal thermal energy storage (STES), also known as inter-seasonal thermal energy storage, is the storage of heat or cold for periods of up to several months. The thermal energy can be collected whenever it is available and be used whenever needed, such as in the opposing season." https://en.wikipedia.org/wiki/Seasonal_thermal_energy_storage

Solar is only really crap from about the middle of December through to about the middle of January. Peak heating demand in most of the UK is in January but in the west country is February. Using a small battery to iron out the sporadic pockets of sunshine is a must it seems or the heat pump won't have time to warm up. I'm not sure why many are against oversizing solar arrays so they work better in winter and clip in the summer. Panels are incredibly cheap if you buy them by the pallet. Inverters are hardly expensive and can be DC oversized if you need to. There are also techniques for spreading out the power band (e.g. east-west arrays). Fitting them yourself is incredibly low effort if you have a good electrician that will sign off the inverter to grid bit (or some prefer to run the cabling themselves once the array is up). Anyone that has ever lifted a tile on a roof is capable of fitting them on a pitched roof and on a flat roof it can be as simple as a ballasted system. Is that not precisely the point? If it took that much energy to heat up it now has a store of energy which is released back to the house (presuming the thermal mass is on the inside of the thermal envelope). Running heating systems on renewables. It gives you greener, more reliable power. We have had at least 20 power cuts in the last 8 years here it has been ridiculous but our solar and solar battery have run perfectly since they were installed 5 years back (we don't notice power cuts until the neighbours come round for tea).

This is the layout we went for. No idea if it works well yet or not but from walking around it and placing furniture / people in Twin Motion it seems to.

Welcome, we are doing something very similar to you building a 42m x 10m ICF house in Dorset doing everything but the frame / subframe ourselves. It is a little out of the ordinary so you may receive some pushback but there is a wealth of expertise and knowledge here on the forum. It is worth listening intently to what people are saying (and then being willing to discard some of it after careful consideration). There are of course efficiency issues with having a building shaped long and thin like this (yours even more so) but they can be mitigated in many ways. Depending on the orientation of your roof and shading you should have an enviable orientation for cheaply fitting a very large solar installation. The majority of the cost these days is in the mounting system not the panels. The panels are cheap and getting cheaper. You can also use techniques like DC oversizing (up to 200% these days) which let you save costs on large inverters and avoid arguments with National Grid. Add DC linked batteries and a DC linked EV charger to make it even more useful. With an ASHP and underfloor heating you effectively have a heat battery that will take a few days (depending on building fabric) to discharge. Deferrable loads, TOU tariffs (time of use tariff) and renewable energy all go hand in hand. I hope we stay in touch as I think we probably have quite a lot to learn from each other, cheers. Other members with projects that may interest you are: @BotusBuild Who is currently building his own ICF house to an incredibly high standard. @TerryE Who built a large multi-generational home in 2017 @AliG Who it won't let me tag as I've run out of tags on this post. Built a 1000 m2 ICF house

There is no requirement for planning permission for any heating method other than ASHP (and even then only if you already have a wind turbine or a second ASHP fitted). Unless there is a planning condition specifically requiring the use of an ASHP what you decide to do is completely up to you. I have driven a rental Renault Zoe and I can quite see how it could leave a bad taste. I've driven many EVs since and they are all much better. Many of them significantly better than any ICE vehicle. Don't let a crappy implementation put you off a good concept. As for whether an ASHP is going to lead to high bills or a cold house there are too many variables for us to comment properly. There is some real world data available here: https://heatpumpmonitor.org 1. Radiators (oversized?) or hydronic (wet) underfloor heating? 2. What is the overall U-rating of the building fabric including transparent elements? 3. What is the air-tightness of the building? Do you have an MVHR fitted? What is the controlled ACH (air changes / hr) you are aiming for? 4. How thick is your screed? Is it insulated underneath? 5. What size ASHP did you go for? How many m3 is it having to deal with? 6. Where is your electricity coming from? Solar? Wind? Grid? Can you get on a TOU (time of use) tariff and set your heating controller accordingly? 7. What is your control strategy? (e.g. get it up to 21 degrees and let it sit there, juice it with cheap TOU or renewable energy when you can. Most of these considerations would apply regardless of if your source of heating was oil, gas or a heat pump using electricity to extract heat from the air. You will be fine with a well designed and fitted ASHP. There are also safety issues with other fuel sources that don't apply to ASHPs. If you are worried about being instantly able to change the heating you should take a look at infrared heaters. They respond almost instantly.

This law (part of the Consumer Credit Act 1974) protects you if you use your credit card to buy something costing over £100 and up to £30,000 Depending on what you are buying you might need to structure your payment into two smaller payments.

Hello and welcome! I hope the house buying process is as painless as possible. This is a great point, following on from this don't forget you can setup a catch all address quite easily. You can then give out a different email to each supplier and sort their responses automatically into folders. It has been very helpful for us. E.g. acmeplumbingfirm@example.com or mvhr@example.com It is also useful for ongoing bills e.g. powerbill@example.com or waterbill@example.com

I think you misunderstood my comment, I used troll as a verb.

You are welcome to participate, you are also welcome not to participate. I'm not sure why but SteamyTea has decided he will sit on the sidelines and chuck in unhelpful comments. He has even stated clearly this is his intention twice in this thread. This is a waste of his time and our time. If my politely asking him not to do that makes you not want to participate here I can only apologise and wish you well.

What inverter are you using? You can normally get that info out of them but may need to use the serial port. Apologies if this is common knowledge but I was unaware ASHPs took time to spool up. How long does it take?

Finding a plot is incredibly difficult. There may be some hope on the horizon if planning rules change significantly. There is also always the possibility of a paragraph 84 (previously paragraph 80) house although that is likely to be a big undertaking. https://studiobark.co.uk/resources/paragraph-84 Good luck with your build!

Pardon my ignorance here but would the immersion heater (CoP of 1?) not be incredibly inefficient in comparison to the ASHP (CoP of 4 to 5)? Why not fire the extra juice from the panels directly into the ASHP and skip the immersion? Sure you'd have to upsize the ASHP slightly but would the efficiency gains not quite quickly pay for that? You can then use that energy for other purposes or even export it.

I'm very pleased for you (and your son!) that it has all worked out so nicely. Well done for all the hard work. Great to hear how quality craftsmanship / materials really do allow the creation of low maintenance buildings. That you managed to do it on a tight budget doing a lot of work yourselves is even more impressive. That's a good rule. I'd also add don't pay anyone to do something you enjoy doing or enjoy learning to do. Hard work does take a while to recover from but it is ever so satisfying, I bet you all enjoyed working together to create something so nice. We are reasonably young compared to most self builders so stiff upper lip time I suppose. From the sounds of your post you feel like you made the right decision. Minus garages / workshop / gym and spaces that really don't need standard finishes we have about 600m2. We don't need all this space yet but we will grow into it as we need it. I only get a VAT refund and CIL self build discount once. Demobilising / remobilising, inflation and economies of scale have a hand in my decision. As does the current geopolitical state of the world. Our globalised supply chains are fully functional right now. They weren't a few years back, will they be in a few years time? I'm striking whilst the iron is hot. I hear you and I appreciate you taking the time out your day to warn me against doing anything silly. I would however suggest that a 1,200 m2 build (particularly with the large ancillary spaces we have) is not 5x the effort of a 230m2 space. We specifically designed our build to be geometrically simple and to avoid architectural fussiness. It is a great big rectangle which makes it simple to build. We also have perfect 360 degree access and plenty of room on site to store materials / equipment etc. This will make life easier. I have a turnkey price here from a very fancy (I swear half their budget goes on brochures) construction management company. They reckon they can do it just shy of £3 million fully fitted out furniture and everything. I reckon they have a huge (40%) profit margin on that and that we can do it for £1.8 million fully fitted out. Of course however we don't need it fitted out to the standard they are suggesting nor do we need all the space yet. I value simplicity and size over fussiness. The goal I've set (which I accept may be impossible) is to get the frame water tight / done inside of £1 million and get the majority of the first fix / some second fix done inside of 1.5 million. There is little point setting a target unless it is difficult to reach. I have every faith in our team, our family and myself. It helps that we ran a building company for years. We are not inexperienced and we have taken our time to use our knowledge to find the right people to work with. We also have the majority of the tools we need and knowledge of how to use them safely and efficiently. I look forward to hearing these thanks for taking the time to write all this up. Have a great weekend. Cheers, NB

You have the 2nd highest comment count in the thread but it seems you are focusing on quantity over quality. Can I please ask you again to go and troll somewhere else. I have no interest.

Will take a look cheers, someone made an ESPhome device that integrates this with Home Assistant here: https://community.home-assistant.io/t/brink-flair-325-heat-recovery-unit-esphome-modbus-integration-5/423182

Wise man. It turns out even the things I thought were absolute certainties aren't. For example MVHRs are potentially of dubious utility depending on latitude and other factors it seems. I guess speaking in general terms "MVHRs work" or "MVHRs don't work" is a fool's errand. The more I learn the less I know.

All helpful comments warmly received, if your goal here is just to go on the wind up can I ask you do it somewhere else?

I'm not sure what you are getting out of derailing this thread but can I kindly ask you to stop.

Perhaps a subject for its own topic, just like the somewhat tired "is wikipedia a good source" debate.

I think this is offtopic if you don't mind us steering it back. I'm perfectly happy for anyone in this thread to use either of the terms Thermal Mass and Thermal Inertia. We all know what we mean.