Mugwanya

@Triassic https://www.aircondirect.co.uk/p/1488434/multi-split-4-way-wifi-ready-inverter-wall-air-conditioner-system-with-four-9000-btu-indoor-units-to-a-single-outdoor?wgu=272195_196673_16135521108755_5842930f28&wgexpiry=1621328110&utm_source=RedBrain Ltd&utm_medium=webgains&refsource=webgains I'm building a three bedroom house so I'm thinking a cassette in each bedroom plus one in the main living area which is open plan with the kitchen. I have no idea how well they work but it will be an extremely well insulated, air tight house so a little heating and cooling should go a long way.

How much will it cost to get your house connected to the grid? The quote I had was £24k, so spending anything less than that meant that the payback for solar was immediate. Also the panels plus mounts are £116 for about 2 sq.m. and slates were quoted at £40-60 per sq.m. so depending on the quality of the slate chosen installing solar panels cost no or little more. I'm installing rainwater harvesting for eco reasons and I agree that on straight cost terms it's not worth it. I also don't think my air to water heat pump cylinder, at just over £2k, can be cost justified over a standard cylinder which would be around a thousand or less, particularly since for over 6 months a year I won't be able to use half the solar energy that I could potentially produce so a standard immersion cylinder would be fine. But again it's a long term eco thing. Installing and air to air heat pump for heating and cooling, at around £1500, is for comfort so again there is no monetary payback from it. But what price do you put on being cool in the summer?

Why so many solar panels? The panels cost £83 each, with and additional £33 fir the in roof mounting trays. The panels are about 2m2, so about £58 per sq. m. I was told that decent skates are £40-60 per sq. m. So I decided that a small increment in cost to put in solar panels was worth it to maximise my production in winter. Also adding additional panels at a later date would be very expensive; installing the maximum number supported by the roof stops this being an issue. My payback period is also immediate as long as the total cost of the complete system is less than the £24k that would have been needed fir a grid supply.

Foundations go in 11/12 March. SIPs@Clay have quoted a 10 week delivery time so should be erected last we in April or first week in May. I'm going for 56 375W Long solar panels, 3 Voltacon Conversol Max inverters (7.2kW each), 6 Pylontech US3000C batteries but with scope to go to 16 after next winter once I've seen how the current setup performs. The idea is to use it ourselves over next winter in order to get some stats; we live 5 miles from the house so if we run out of electricity then we just go home. The online calculators estimate that there will be 11 days where there will not be enough power and I can reduce that by adding more batteries. I am in a debate with my suppliers at the moment about generator sizing. The perceived wisdom is that I would need to go for a 10-15kW model to supply the load when the batteries are depleted. I am arguing that I could go for a 3-5kW model, have it start when the batteries are, say, 30% full, and run it until they are 90% full. So the generator is never supplying the full load of the house but is in essence just keeping the batteries topped up. Essentially the battery would just be backing up the solar supply, and would just need to provide around 15kWh over a 24 hour period, with the batteries always providing the load for the house. Windows and door supplier has not been chosen yet. Air tightness will be provided using VP400 Plus WRB on the outside, supplied and installed by SIPs@Clay, and Intello Plus on the inside, supplied and installed by myself. There are three en-suites and one bathroom, and I plan to use Schluter Ditra products to create wet rooms, because I've watched Matt Risinger on YouTube. Any comments on alternatives would be gratefully received. Plumbing will be either Tectite, Hep2O or Speed fit. I get the impression that the Tectite is more solid but more expensive, and there's not much to choose between the other two. I plan to buy some samples and play, but I don't expect that to help me choose between them as I'm sure that they all work. I have an electrician, joiner and plasterer lined up but not the plumber yet so his advice will be crucial. There will be two cylinders, an Ariston Nuos air source heat pump 250l cylinder (for two ensures and the kitchen) and a Mixergy (for the third ensuite and the bathroom). This is because I like the look of both technologies and want to play. The only other issue is whether to use timber I beams, as specified by the SIP company, or metal web joists (Posijoist) as recommended by all the MVHR companies I've spoken to. So at the moment I'm hoping to be ready for some bookings in Autumn, Covid permitting, Winter usage by friends, family and myself, followed by a full opening next spring.

They did send me a list of about 30 companies who could do the work. I gave up after ringing 18 of them, all of whom said that the job was too small. The others on the list looked like they would have said the same thing i.e. had websites boasting about how many big projects they'd done, with nothing about one off connections. I will say that the gas quote was a lot more realistic (in terms of my budget), hence opting for a gas generator.

I've been quoted nearly£24,000 for my supply. The nearest supply, the next door neighbour, is 30m away and there is an unused 3 phase cable at that point. On the excellent advice of people on this forum I pursued getting a grid connection, despite my feeling that it was a rip-off, but then they said that it couldn't be installed until later in the year. So I gave up, and am going off-grid. I had already budgeted £10k for the solar to run alongside the grid, up that to £22k and I have solar capacity to run the house for most of the year plus a generator for the days I need it.

Couldn't find much info on the Aurora's, but what I did find seemed to indicate that they are not off grid, and there was no mention of using them in parallel in order to support 16kW of solar.

I've not heard of Aurora, I will look them up this evening. It looks like for single phase off grid use SMA recommend the Sunny Boy 3.0-6.0 solar inverters, so I'd need three of those, and then the battery inverters on top. I can't see at the moment where it says that the inverters can be paralleled, but there is talk of a cluster so I'm assuming that that's the same thing. So it could be a good choice, it has the same basic design as the Victrons but integrates the controller's so less clutter and easier install. And there is at least some comments that they are reliable. My guess is that the price will be a bit over £4,000, do a lot cheaper than Victron but more than the Conversol. I will look into what advantages it has over the hybrid inverters, check that my assumptions are correct and then maybe add it to the list. Possibly removing the Victrons. Thanks for that. Derek Mugwanya

Does anyone know if there is an equivalent to the MyEnergi devices that will work in an off-grid environment? This would allow excess solar to be diverted to a hot water tank or car charger.

So the quote for the Victron solution comes to £6,420 excluding isolators and assorted cables. The comparable price for three paralleled Conversols would be £2,700. A considerable difference but firstly the Victrons look to be much more expandable (though at this moment in time I can't see that I would ever need that expandability, I am new to all of this and there are certainly things that I'm missing) and secondly there is a lot of evidence that the Victrons are extremely reliable, and next to nothing (good or bad) that I can find about the Conversols.

Hi Has anyone any experience of Voltacon inverters, in particular the Conversol Max4 7.2kW? I'm putting nearly 16kW of panels on the roof of my new build and need to source the inverter. It looks like 2 Conversol would exactly suit my needs, with the other option being three LuxPower LXP 5000s at a significantly higher cost or a Victron solution being recommended by my supplier at an even higher cost. So I'm looking to see if there is any experience with the Conversols? Thanks Derek M.

Are there any good suppliers of the Mixergys that I can talk to? I've gone through the process of looking at the Sunamps, Ariston Nuos and similar heat pump cylinders, and also separate cylinders and heat pumps. This product looks good, particularly with its relatively low cost combined with the fact that I expect to have a lot of surplus solar for 8 or 9 months of the year.

Just had news that the new plans have been approved; the architect is starting the technical drawings so they should be with the SIP supplier early January and I'm pencilling in the foundations for early March and the structure shortly after. I'm starting to get excited.

Ok, unless the council come back with a no on the updated design, pretty much all is decided. We are going off grid for the first house; 40ish solar panels and 24KWh of battery storage with a 10KW gas generator, total cost including the in roof mounting for the panels and a gas connection purely for the generator coming in at less than £20k. We'll use the data we collect to decide whether to get the grid connection before we build the second two homes. HTTPS://jaleve.tribe.so

Western Power know that there will be three properties eventually but only one built this year. The quote doesn't explicitly say it is for just the first property, but it is for three phase so I assume that that will handle all three houses.

@scottishjohn I'm only planning/able to build one at the moment, the other two will start in 2 or 3 years time.

Sorry, the shower timer and bath depth bits were not serious. The outdoor dog shower was serious, if it can save on internal cleaning and wear and tear.

Maybe I need to look into a shower timer - set it for 6 minutes max, then 10 minutes before the next one can start. Also 6 inch deep baths - I could claim it makes it easier for old folk to get in. But the warm outside tap/shower for dogs is interesting, I may look at that.

But in a holiday let I can't dictate how, or how long, people will shower for. We don't have a shower at home do if we go away my 6 year old daughter will have 45 minute showers. I'm in for probably 15-20 minutes on top of that.

I have already seen Vanessa's site, my plot is nowhere near the sea - probably as far from it as you can get in England - but everything else applies. In the same way that I will take the advice about going on grid, I will take the advice of the agents and put in a bath. I agree with Jeremy that they are not that bad, water wise. And LOML would never agree to not accepting dogs.

Next summer season, I see no way that it is going to be finished this year. Only the ground works have been started do far. And I have accepted, and appreciate, the views that I need to go on grid, the only thing I'm looking at is if I can do it next autumn (2021) rather than straight away if it is going to cost 23k, plus talking to independent companies to see if I can get it down to nearer 10k, which is in my budget.

@Mike Yes, I can limit the scope for energy usage. LED lighting was already in the plan, induction hob which used less electricity. But there is a limit how far I can go down that route. People renting a property, potentially for up to two weeks, are going to expect an oven and washer/dryer. I might get away with no dish washer, and all appliances will be as eco as possible. I will consider the bath issue as one wasn't on my original plan, but again the company who will be renting them out for me were quite keen on one; the argument was that guests coming in with muddy dogs or young children will want a bath, so the revised plan has a bathroom with bath just off the entrance lobby so that dogs/kids can be herded straight in.

Yes, it will be three water supplies and I've built three standpipes. The question is can I put the 3 pipes in one housing or do I need separate housings. Paying 23 grand for the grid supply kills my budget, which either means comprimises elsewhere or I put the grid supply in later as the money becomes available. I think that the solar plus batteries plus a generator will suffice for the summer season, so the plan is to get the grid in next October. Unless alternative suppliers can reduce the cost of the contestable works.

And I'm talking to a company about doing the installation of the renewable stuff, I'm half hoping they'll say that it is overkill and reduce the number of panels, batteries and maybe one of the Sunamps.

I'm in the UK, in Derbyshire. If I can't get grid power in at a reasonable price now then an option would be to not rent it out for 3-4 winter months, with the intention of using next year's rental income to pay for the grid connection. That may not be so bad, as at the moment with Covid I don't think it will be finished until next year anyway, and if it was no one will be allowed to book holidays. So 10kWh of panels, 17kWh of battery, two 9 or 12 Sunamps fed from a Nuos heat pump and make sure that the solar inverter has a grid connection for later. Then no rentals until next spring/summer.