How To Size Battery Storage For An Existing Solar Installation

[@artisanelectrics]

Request a quote from Artisan Electrics here - app.openquote.net/company/artisanelectrics

[@symeonthorpe3965]

Glad the second customer chose you in the end Jordan. We’d recommended you a few times, glad they finally got in touch 👍🏽 We’re charged with keeping their solar panels clean on a regular basis in our electric window cleaning van 👌🏽

[@charanvantijn541]

Please keep the background music in the background. Or better yet, no background music at all. The only things it adds is annoyance for me.

[@AS-vf7qw]

Holy Hell Jordan! Whatever is your client running other than the ASHP? I have 5.32kW solar PV and 25kW battery storage, my total daily usage, not including EV, is less than 6kW. I charge my Leaf with 39kWh battery about twice per week but do it in eco+ mode, straight from excess solar. Last year, my system produced 5.13 MWh of energy, exporting 2MWh, virtually zero import. I’m staggered at their consumption.

[@wajopek2679]

It’s the hidden heated swimming pool that you don’t see 😜

[@UndercoverFerret404]

At that 2nd system (12:20) it would probably be more beneficial to have a larger storage tank for the heat pump, so that could be heated with solar. It's clear that the house was heated by the sun during the day, and at night the temperature dropped and the heat pump started up.

[@Goreuncle]

Also, they could hire specialists to improve the thermal insulation of the house, heavily reducing the heat pump's consumption. That has to be way cheaper than buying all those batteries + installation costs.

[@IanFarquharson2]

In the first example, the car charging in the evening is not realistic off a battery, 20kwh a day or so. They’ll be better off with enough storage for sundown to midnight, then charge up car and battery off cheap rate. Then discharge battery until the sun is giving more than the house baseload.

[@IanFarquharson2]

Update on this - I’m now in the Solaredge TOU beta. Some days the system helps to charge the car by providing 50% of the 7.4kw draw. Stops at about 20% left in battery with the assumption that it can easily cover the morning house draw while recharging again. It’s still halving the 7.5p/unit cost, and making space for tomorrows excess.

[@sparkymark75]

I have a GivEnergy battery and use Home Assistant to take the solar forecast for the following day and figure out how much to charge my battery using the cheap rate with the Solar production the following day charging the battery up the rest of the way. It also pulls in Intelligent Octopus charging sessions when I've plugged my car in and prevents the battery discharging during those times.

[@leetipping-ns3yn]

​@@IanFarquharson2using DC to AC to DC is such a silly endeavour. Especially when DC to DC can override the speed limits in EVs

[@phil_nicholls]

Without putting the data through a spreadsheet, it’s difficult to gauge exactly what size battery is best. Though I appreciate that most battery systems come in very ‘un-handy’ sizes, so generally a multiple of what’s available will have to be used. We have an almost identical sized solar system (9+kw, East/West split), and have a single Powerwall on it. We are finding that a single PW is just a tad too small, particularly in winter months, where we charge overnight on cheap rate, and run the house from the battery until the next charge cycle - with any solar being just a small bonus, as winter solar on an E/W system is paltry. The thing is, we often, in winter, run out of ‘juice’ by early evening, and end up importing from the grid at peak rate. So we need more battery storage - and another PW is on order. But that means we’ll end up with 27kwh of storage - overkill somewhat. The original system had a payback of just 5.8 years - the second PW will take 10 years to pay back. So it’s more of a heart vs head decision - though there are other benefits, such as better smoothing between Sunny and dull non productive Solar days, and better resilience in the event of a power cut (we live remotely, and have power cuts several times a year - to the point where we have a generator hooked up to the house too (which we haven’t had to use since getting the first PW)). For most people, I think the length of payback for batteries is the major hurdle - unless you know you’re in your forever home, it’s a hell of an expense that might not payback before you move on. Also, unless you’re a high user of electricity (we are), you may never see any cost benefits - as the savings are to be made against using a lot of power at peak rates - which, if you’re a low, or moderate user of electricity, you’re never going to realise. So while Solar and batteries make perfect sense for some (like us), the returns for many just aren’t there. Though, as more and more new builds move over to ASHP for their heating needs, solar and batteries will come into their own - but at the moment, it’s still a hell of an expense for most.

[@deang5622]

No, you don't need a spreadsheet to do the battery sizing calculations. It's quite easy to do with pen and paper. The difficulty is the assumptions you make. Firstly, you have to decide on what time interval you want the batteries to provide power for. Typically 24 hours or less. Because every 24 hours you've got another day in which to replenish the energy in the batteries. Second, you have got to calculate how much energy in kWh you are going to consume over that period. That's the energy which the battery needs to store. If the batteries become depleted because you don't get enough sunshine day after day, as would typically occur in winter, you can always switch to grid power. In an off-grid scenario, living in the wilderness, you might want to do things differently and adopt a different design strategy where you retain more than one days load's use of charge in the battery as there is no guarantee you will replenish all the charge used by the load in one day. That's a different ball game.

[@deang5622]

The pay back time expressed in years is not the only way to decide if the solar panel system is economically worthwhile, and who decides what is viable, does a 2 year payback time make it economically worthwhile, or is it 5, or even 8? How do you choose? The proper way to calculate it, if you have a property which you can power from the national grid too as well as solar is this: - calculate the pence per kilowatt hour of electricity generated by the solar system and compare that to the unit rate (also ppKwh) from your electricity provider. Remember, you're getting electricity from the sun, but you could get it from your electricity provider. And you need to choose the cheapest, if you are looking at the solar PV system purely from a commercial aspect and not considering it for its green credentials. If the ppKWh of your solar panel system comes out higher than your electricity supplier then you shouldn't install it as it is not saving you money but costing you money. Now, calculating the ppKWh from the solar system is not easy, you have to make various assumptions about the life of the panels, how much kWh they can realistically produce over their life time, how much sun you are going to get, maintenance costs, battery replacement costs. Add to that the ppKWh from your electricity supplier can change massively over a 10 or 20 term. So ideally you want to factor some variation of this in to your calculations too. I have seen too many people talking about pay back time but this doesn't give you the clear information you need to calculate whether financially, you are better off installing a PV system or continuing to use grid power without the PV system.

[@markbrown9803]

You can always take the battery with you when you move if it helps you rationalise the cost

[@DrRogB]

Just pick the tarrif with the biggest difference between day and night and the pay back comes tumbling down 😊.

[@deang5622]

@@DrRogB But who says pay back time is important? Who says a pay back time of Y years is acceptable and X years is not? Is 3 years acceptable, or 8 years, and why?

[@tach175]

You need to take in to account export, some pay quite well, all depends on what your on

[@gingerninja7187]

Wow these type of customers must have a lot of disposable money , im curious how much all this cost

[@alanmuncaster7357]

Having 9 KW PV arrays on east and west roof we found that a single 8.2 KW battery did not provide enough storage, especially with over cast days. Last year another 8.2 KW battery was added and 16 KW gave us the buffer we needed. Mid winter we set the batteries to charge using imported off peak to charge to 75%. This has worked well. By the end of Feb the overnight charge turned off. Certainly a big improvement,

[@electrician247]

Be interesting to see the payback period on this one. I thought about a 24kW battery system at my own home but the costs when export rates are climbing didnt make sense. Went for 12kW as a happy medium and I suspect in a few years I wont be storing anything as export rates rise. A hard metric to sell longer term payback periods with such a fluid and varied energy market. I worry we are next the PPI in over selling what payback and energy independence actually looks like. Good video though.

[@ForTheBirbs]

That's really interesting Mark. In many parts of Australia (particularly South Australia) there's now too much domestic solar export. Grid voltages have been pushed to 260V to force shut down of export. This will level out once a absolutely huge new interconnect is complete, linking SA to Victoria and NSW. Export rates have plummeted over the past years here.

[@electrician247]

@For the Birbs (Jim Hooke) hey Jim! You have one reliable and pretty bright feature we lack over here 🤭 sunshine lol That said we will need to invest in local street level infrastructure for this to be a long term boom/thing. The grid at a HV level is pretty robust and capable on our little island. But once we step into the 400V distribution system things are a little limp tbh! Hope the birds are all good and life treating you well!

[@deang5622]

Made the same mistake twice. Battery capacity is measured in kWh (or Ah), not kW. It is really important to understand and the difference. Don't drop the h because you don't understand it. Go learn the difference between these units.

[@electrician247]

@Dean G you think I don't know the difference? Come on Dean be sensible. This isn't science class my friend. Lighten up.

[@steveatkinson2196]

BTW modbus is just the protocol used.

[@rattlehead85]

This is a super interesting video Jordan. Will be looking forward to seeing the install step by step and the results from it. Great stuff

[@Ben-gm9lo]

Thanks Jordan. During your analysis of battery size, you never mentioned what the deep winter heat pump consumption was. This is the real stress test for a battery system. It has to be big enough to power the domestic needs with only a modicum of solar production and the rest coming from off-peak electricity. As well as capacity, battery charge and discharge rates have to cope with the heat pump's demand and the need to fill the battery during just a few hours of off-peak. I also feel that we are missing the fact that battery systems are projected to lose capacity as they age. Most manufacturers guarrantee only 70% capacity after 10 years. Shouldn't we thus oversize at install to help compensate? Anyway, love your content, thanks so much for all the education and entertainment. You lack the 'rough edges' of so many similar content creators. If you could just quell the music volume between commentaries then I would definitely give you a 10! I hate having to turn volume up and down because some young buck likes loud, evocative music!

[@randomcamerajunk6977]

Biggest domestic single unit heatpump draws about 2kw peak load without an aux heater running.

[@Ben-gm9lo]

@@randomcamerajunk6977 Even if that is an applicable figure for the heating the enormous place in the video needs, that is still something in the order of 20 kWh a day? The solar will be putting out a fraction of that, so any battery needs to power the remainder or you end up pulling from the grid. What am I missing here?

[@mwnciboo]

​@@Ben-gm9loPretty much rule of thumb is "As much as you can comfortably afford". You identified the key being offpeak - recharging in winter. In Summer bank as much as you can - and with a resevoir you can massively insulate your self from the Generally 3:1 buy back (e.g you generate 3kwh to buy back 1kwh from the grid when you need it) this is of course economically insane but needs to be balanced against the outlay of Battery Storage. If you can get 30kwh in storage I reckon for most that is enough - I used wood burner heating with hot water - so my power is lighting (LEDS) and low consumption electronics. I can last for days in winter in off grid.

[@bjornsymoens6539]

Perhaps look into using the smart grid contact on heatpumps. This allows them to increase their working point when excess solar is available allowing a lower working point during the night. This way you have a thermal battery and this from my experience has been way cheaper and effective in reducing power consumption when a customer has a heat pump.

[@Sandra-mv7xm]

Could you explain further? Thanks

[@MrLister]

If you're not already aware, SolarEdge provide their designer tool which allows you to explore different options of inverters, panels, batteries etc. It produces great reports on estimated self consumption, clipping etc for an entire year. No need to guess from eyeballing a few days data from an existing system when it can be modelled properly.

[@jneale7715]

It'll currently be the best time of year for solar peaks of generation, i.e. lots of sun and cold temperatures making the system efficient. In warmer months the temperature is likely to reduce the top peaks. However total output for the day may be higher as less clouds.

[@johndoyle4723]

Thanks, everyone is different in their usage profile and needs a different solution, so yes your analysis of use is very important. Putting extra battery storage in so that you can charge an EV at night seems a poor use when you can import at 7.5p/unit on Octopus intelligent, I am lucky, I am often at home during the day and can charge my EV on solar. The battery will always be too big in Summer and too small in Winter if you want to minimise export, and import, very difficult to get the best size.

[@rugbygirlsdadg]

I have a 10kWh peak system split 5/5 East/West installed mid Feb which has generated over 1.5mWh. With and Eddi and Zappi (but low mileage EV) April will be my first £0 bill month. That includes gas c/h. I'm having 2*5.8 kWh Solax batteries installed end May with a 5kW AC charger with built-in EPS.

[@onlymise2758]

Hi Pal Love this channel ... A question if I may .. See the Skirts around the array , could there be an issue with air flow under the panels ... I'm a solar Installer from Dublin Ireland ..... Keep up the good work . Great to see work done with skill and pride .. Thanks

[@robdeboer2293]

Solar panels perform better in colder conditions, skirting heats it up :(.

[@alisterg3582]

Easy to suggest a 20kWh battery when its money coming in and not going out. In the first case surely excluding car charging from the data would have made sense - put them on an off peak tariff where the car is charged and the house base load covered for the 6 hours off peak and it looks like 10kWh would be ample. With only supporting 5kWh from the inverter they would still be importing 40% of the peak load shown from the grid (presumably at a standard variable rate).

[@Umski]

You don’t make money not selling more stuff 😉

[@eddybonny2877]

You should really consider using the house to 'store' energy (heat) during the day. With a glut of 'free' solar, turning on the heatpump during the day to pre-heat the house with 20, 30, 40? kwh of energy will offset evening usage. It is also WAY cheaper than the equivelent battery.

[@Electronzap]

I think you should always plan for adding more battery. Invest in maximizing the solar to begin with, and then add battery capacity as you can afford it, for as long as you are both exporting and importing. Could even buy a portable UPS power bank to set next to things like the heat pump, which recharges during the day from an outlet connected to the solar and grid.

[@scottcameron8936]

How does a power bank work? I have a small system 2.4kw and about 50% is exported despite our best efforts and would like to reduce this.

[@Electronzap]

@@scottcameron8936 A house with solar and batteries is basically a power bank. Once the batteries are fully charged. the extra power has to go somewhere or be lost. So I'd have another battery system (power bank) that charges from the outlet when the house's batteries are full. and then use that stored power to also power stuff when it's to dark. It's like only charging an electric car when there's enough sunlight to do so and power the house.

[@soodax]

Thank you for an informative and nice explanation. I'm just curious to why it is important to raise the self usage of produced (Solar PV) electricity. What are the incentives? If it's economical I would like to know the payback and LCC of the extra installed battery capacity.

[@P0wnHell]

The question one has to ask themselves though is, after installing so much battery storage, how long, if ever, does it take to recoup your investment. I've recently done the calculation, and it didn't make sense for me to get battery storage

[@simcax6087]

Yepp, it seems no one here considering how much electricity you can buy for the price of that battery pack. You basically just pay your electricity in one big sum for the next 10-12 years.

[@Umski]

Bigger = better when you’re selling stuff 😬🙄😉

[@northeastcorals]

Exactly what I was thinking, lots of videos breaking down the pay back of entire PV systems but I've not seen any specifically for the batteries. Also nobody seems to factor in the fact that the batteries only last about 10 years so you have to factor replacing the batteries into your payback time forecast.

[@andymcnish]

I understand how you are trying to maximise use of the solar produced in this home (and the off-grid and general green benefits of that), but, whenever I do the calculations for this, the cost of batteries simply isn't worth it once you take capital and replacement costs into account - especially assuming that battery prices will drop and effective battery lifetimes and the availability of vehicle to grid EV cars is likely to increase markedly in the next few years. I'm not sure what a professionally installed 20kw battery system here would cost, but I'm going to guess £20,000.Tell me if I'm way out. And I'm not aware of any battery supplier that guarantees their batteries for more than 10 years of daily charge/discharge cycles. So you can really only budget for them working for 10 years. Even if that 'saves' 20kw/day from being imported the savings are only going to be (at theoretical best) the difference between the cost of using that yourself and the additional amount you would pay to import it overnight as compared to what you get paid for exporting it in the day. As an EV user, the homeowner could go on one of several very attractive Octopus Energy packages that may reduce this significantly, but lets just assume they are on the current Octopus fixed export (15p/kw) rate and their standard 33p/kw import one - so the saving is 18p/kw. So for 20kw that's £3.60/day or £1314/year. First there is the cost of paying interest (or foregoing investment income) on the £20,000 you're spending on the battery - let's assume that's 7%/annum - so £1400. So even at max theoretical savings (which you won't actually get every single day), the cost of interest (or lost ROI) alone on that £20k is going to outrun your annual electricity cost savings. And then there's paying it back/replacing the lost capital - for ease of calculation let's say at the end of the 10 year period - so £2000/year if you amortise it. So you're basically at least £2k a year worse off than you would be if you didn't install a battery. And if there are any issues with the installation, solar panels, inverter or batteries, or you want to move house before the 10 years is up, then the maths gets even uglier. I can see how a solar panel install is worth it. But I can't yet convince myself that a battery installation alongside it works in terms of pure economics - so I'll wait for cheaper, better batteries (or a £20k V2G car that sits on my drive most of the day and I can use both as a home battery and as a vehicle).

[@judebrown4103]

Perhaps for this customer it isn't all about economics but rather a desire to be as near to off the grid as possible. Perhaps they like knowing that they are running their home and vehicle on pure sunshine.

[@andymcnish]

@@judebrown4103 Absolutely. And those are the other benefits I mentioned in my first sentence. But in the middle of a cost of living crisis, it's really only the well-off who can afford a big solar panel installation and a 20kw battery. What we really need for a greener UK is mass adoption of rooftop solar (and other energy saving/green technologies) not just by the wealthy middle classes but by everyone.

[@markmuir7338]

Given that energy storage capacity is the main bottleneck in increasing the cleanliness of our grids, I find it amazing that so few places incentivize home batteries. To be clear: I'm not saying this should be government subsidies - instead, the customer should be able to choose to be exposed to something closer to the wholesale price of energy in real-time. Then a battery system would pay itself off in a very short period - just like it is for grid-scale battery schemes.

[@andymcnish]

@@markmuir7338 Octopus' Agile Tariff is based on real time cost for both import and export, I think. And I can see a case for Govt support for mass decentralised micro solar generation and storage as it effectively would replicate the energy security currently offered by very expensive coal, oil and nuclear plants which are otherwise needed for grid back-up and covering peak use times. The cheapest energy is now the cleanest - large scale wind and micro-generated solar. And they are getting cheaper year on year. I've no issue with batteries being used for extra micro-storage for the grid or for maximising personal use of a home's self-generated solar - but for both they only need to cover the peak period between sundown and 11pm (and possibly 7am to dawn in the middle of winter). In daylight your solar panels will provide most or all of what you need anyway and between 11pm and 7am you should be able to get cheap off-peak electricity from the grid's spare capacity. Unless and until borrowing costs come down again (or the UK Govt (as the Scottish Govt does) provides interest free loans for the most common types of domestic installations, or unless electricity costs increase significantly or battery costs and longevity improve a lot, batteries just don't make sense financially. In fact, if you have to borrow at commercial rates, even panels don't make much sense at the moment - they are basically break even at best if you have to borrow at 6-7% to fund them.

[@markmuir7338]

@@andymcnish Indeed - that's why most home batteries are 4-5kWh - just enough to peak shift the average home, which would go a huge way towards decarbonizing the grid. An incentive would get those installed sooner, and those batteries benefit everyone - not just their owners. My house in Southern California has a 5kW solar array producing roughly 40kWh/day most of the year. This provides 125% of my typical annual energy needs, and paid itself back in 6 years. But I was only using 24% of the solar energy at time of generation (self-powered). After accumulating many years of data, I specced a battery to be able to maximize my solar usage. That ended up being 27kWh. Which I have had for just over a year now. That made my house (and car) 89% self-powered over the full year. However I won't save a penny by doing that - the electricity plans here are just time-of-use with net-metering. There's far less competition here than in the UK. There's also the law of diminishing returns. To get the remaining 11% would need a battery closer to 1MWh! Obviously that would be silly - it would be better to just install far more solar panels and over-produce, especially if the excess during summer could be sold for water desalination or something.

[@MarkCarline]

This video is great (and still relevant today) but I think its too focused on kWh usage and self usage of self generation. How about a video which makes the most of Octopus Agile tariff & battery ?

[@marshp3]

When the Artisan bill drops... its remortgage time. 😂

[@Chris_In_Texas]

14:25 Jordan, have you checked to make sure that the phases are somewhat load shared correctly in the house, so they can take full advantage of three single phase systems? 👍🤦‍♂ Looking forward to seeing that!

[@olgaangelovskaya2008]

Is it better to install two 5.2 Kw batteries or one 9.5Kw? Advantages and disadvantages of the 2 solutions. thanks

[@lewisbrand]

Most properties in the UK use between 8000 to 12000 kilowatt hours per annum. This equates to around 30KWH per day. If you fit a 50KWH battery ( around £22,000 ), have solar panels, and arrange a deal with a cheap overnight rate ( 11pm to 5am ) of around 8p per KWH, it is possible to have all your house's electricity usage at that reduced rate ( plus of course the depreciation and cost of installation of the equipment). 10000KWH at 35p per KWH is £3500. 10000KWH at ( for arguments sake ) 10p is a saving of £2,500 per annum. With the life of good lithium batteries at around 20,000 cycles plus, it's a no brainer if you have the cash upfront to install it. In fact, solar panels aside, it makes financial sense to store cheap rate electricity overnight for daytime use.

[@doneisenhuth408]

Do electrical suppliers charge a daily service fee on consumer services. In country NSW we are charged $1.75 aus or 0.95pence/ 1.07 euro each day and thats whether you use power from the grid or not. Very informative video.

[@zomerzet]

In the UK we get a daily 'standing charge'. One for electric and one for gas, no matter what our usage is. I'm currently paying 0.475p for electricity and 10.25p for gas supply daily, before any usage is taken into account.

[@martinbentley1924]

Interesting that neither system is using an overnight cheap rate supply from a company such as Octopus Go and what about Octopus Flux where all of that surplus solar can be sold to the grid at a higher price than the over night rate. Would this mean that the significant cost off such a large battery system would not be needed.

[@Umski]

Indeed these examples seem to have more money than sense 🤦‍♂️

[@UCCLdIk6R5ECGtaGm7oqO-TQ]

Not for a professional install like these, but reckon I'd go the DIY route if I were ever looking to install big storage, as used EV battery packs can be bought and adapted for far less and typically have much greater capacity.

[@philware1546]

PylonTech batteries are cheap, work well and are completely DIY.

[@MikeCarter]

Perfect timing of this video as I was just wondering the exact question about how big a battery should I be buying. Looking forward to the farm install video!

[@authuruksake969]

Rough ballpark figure 2x your PV array. You can be fine with 1.5x PV but 2x will assist if tomorrow is a poor generation day failing to top up your battery fully. You might be fine with a small PV array & scrape by with modest batteries getting you through the evening until say midnight for cheap off-peak electricity to recharge (partially depending on forecast) So you could scrape by, with say 3/4 of your daily usage in battery storage, though batteries often do not offer their full capacity, say 90% or maybe only 80% if cycling down to 20% before charging. Battery cost is a big investment, often more than the panels & inverter, so you need to do the maths yourself, to work out if you scrape by or allow for a bit more room if forecast is quite gloomy Min battery = 1 days usage, perhaps double your PV array if you can afford it (This is a very rough guide as every case varies depending on solar setup & usage along with EV/heating/HW etc...)

[@macky4888]

It more depends on your usage, during the late spring, summer, and early autumn your battery is only basically needed for overnight and occasional day. Outside these times the battery will be used much more, especially during December and January. During those times you can charge the battery during the cheap rate, but your charge rate depends on the inverter, usually 3kW. Therefore during a 4 hour cheap rate, the most that the inverter can fully charge is a 12kW battery. Of course that is if your batteries can charge at full rate in cold temperatures.

[@JimGriffOne]

What size battery do you need? The biggest your budget can support. Literally. That's the only calculation anyone needs: "How big is your budget?" The reason being, the only reason these calculations are made is to reduce the cost for the customer. People who live in a larger house will usually use more electricity, and will also have more space for solar panels. They'll also be richer (big house). So, larger solar system on larger house with richer people = they can afford a larger battery system. Since it's all grid-tied anyway, this is why I say the size of the battery is basically only constrained by their budget. They could theoretically have enough storage for a whole week's usage, and it would do them well. In fact, if you have rich enough customers, they could theoretically (if lawful) have a totally off-grid solution with enough battery backup for months, but it isn't practical for the maintenance costs and the insurance (batteries can blow up and set the whole system on fire).

[@Lewdacris916]

yes bigger is always better when it comes to battery storage IMO, can even sell back during peak hours to the grid

[@johnnybravo9087]

No cost benefit analysis? I’d be interested to see if your battery installation cost has a return on investment.

[@highland-oldgit]

So @ 07:00 did you have to add the 5kW export of the battery onto the current 8kW inverter and have that 13kW approved before fitting the battery ?

[@dfldfl1901]

Love your enthusiasm to add to existing solar PV systems to upgrade them. I am struggling to find a solar PV/battery installer who will work with my existing 2015 solar PV install to add extra solar PV and to add a battery. Most installers want the quick win of starting from scratch. Very disappointed.

[@persona250]

They won’t want to pay for the dno application which could be rejected

[@artisanelectrics]

Get in touch we would be happy to help.

[@Tut-tut-tut]

Please be aware that artisan are NOT MCS or RECC accredited installers. They are technically subcontractors to whichever company provides you with contracts and performance estimates etc, AKA middle men To answer your comment; no issue in adding a battery, an ac coupled battery can be added to any existing system no issue. Unless you were to have a totally separate inverter for any new panels installed, treating it as a new install, and keep the existing system untouched. An MCS Install shouldn’t incorporate any old/used materials if providing an MCS certificate at the end.

[@thenaylor]

Sounds like this guys enjoying selling batteries, their must be better options for the second home, reducing that baseload would be what id be looking at first, and if thats not possible then trying to shift some of the load to when its being produced.

[@Dan-Athema]

First question on an Artisan Site visit: "where do I charge my car for free?"

[@billdoodson4232]

The overnight household consumption will drop in summer as the heat pumps will presumably be off. I can see the batteries being too large in summer and them exporting most of what they generated.

[@hans.vbaalen]

And in the winter there is not enough sun to charge them. The data shows that in March they exported 636 kWh, so roughly 23kWh per day. That means that between October and March, you only have enough sunshine to charge a third of the extra 60kWh, and it'll probably only be in May-August that they use the other 40kWh, knowing that usage will be less those months. But with an array like that, I don't think the owners are mainly in it for financial reasons.

[@billdoodson4232]

@@hans.vbaalen I think you are right. It's a going off grid system really.

[@Sami-Nasr]

It depends where you live, for me you get paid more for exporting than the price of electricity at night, so it makes sense to export during the day and buy at night rate, you need the battery to kick in between sunset and midnight when the night rate kicks in

[@michaeledwards8079]

I have 5.6 KW on the roof south facing and a 5.0KW battery, yesterday my total consumption was 19.48 KW made up of 8.99 from the roof plus 7.0 KW from my battery and imported3.49 KW from the grid so how long would payback be if a new 5.0 KW battery was bought, bearing in mind it is spring and not a lot of sun

[@gonzo_the_great1675]

My back of the envelope calculations (though based on not having an EV, or heat pump)..... The sweet spot for best financial value is size the batteries to be about half the daily consumption of the house. As during winter, you get long days and poor generation, and you don't want batteries peing partly used. And in summer, you have good generation and short nights. So you would only be taking a little charge out of the batteries, starting the next day with a lot of charge left.

[@TheXeroid]

Interesting video Jordan. What is the payback period for the investment in the technology at this customer site? Going to have a new dbl garage built and will be considering something similar.

[@09safzal]

Surprised the first customer isn’t using a cheap night electric tariff to charge the car!

[@tommytinkler1708]

Surely cost of the batteries and how quick they wear out you will be better off importing making 12-15p a unit without the battery hassle?

[@FirstDan2000]

Are there many pros and cons for comparing 2x solar inverters versus a micro invertor system? I was once involved with micro invertor systems, and the simplicity and ease of install (electrically, at least) was staggering.

[@rugbygirlsdadg]

I guess it depends on shading and the logistics of fixing stuff which goes wrong. In a two storey house, scaffolding would be required for micro inverters wouldn't it? That's expensive.

[@Custom_Tundra_XFire_Audio]

60kWh, i didnt write it here but that was bang on what i tought!

[@peterdorning8654]

Money no object !! if you include replacement batteries in 10 / 15 years I wonder what the pay back time would be be ?

[@doakley1987]

Battery will still be sat there nearly full all summer with that array when the heat pumps not being used. Octopus flux export rates are higher than the average unit import rate so might have been more cost effective to them going on to that.

[@DorsetSaferRoads]

can you do a video on the pros and cons of various inverter/batteries please. especially things like integration with things like home assistant/node-red/mqtt, ev chargers and heat pumps

[@RayJohnson1980]

Based on your 27kw array also 3 phases and 23kwh of battery need more like an extra 46kwh for a total of 69kwh

[@QWERTY7773]

Simple question by the time you have paid for the panels the batteries the cost of the install (cables boxes) export to the grid . Then you take into account regulations change maintenance life span of the panels damage (high winds) etc

[@Silky_boi]

The cost of all that equipment has got to be substantially more that just paying from the grid for at least a decade!

[@S88-m5y]

can you set the prices you send the money back to the grid at or how does that side of things work

[@James-zu1ij]

I think even a low electricity user needs a large battery, say 30KW. I have found that My the 14KW batter becomes fully charged quite quickly on a sunny day and then I start exporting. BUT it doesn't last through the cloudy days. The way I see it, you need enough energy to last between sunny days, say 2 to 4 days. Luckily I can put my eclectic car on charge to soak up the extra, but it means leaving the car and biking to work.

[@goldbrick2751]

Excellent video.

[@tomstdenis]

a) if they consume their battery every night what happens if there is a storm and the grid goes down? b) Is the wear on the battery worth the savings from self-consumption?

[@HenryLoenwind]

a) Those are not island setups. When the grid goes down, they go down anyway. b) yes. A battery that is used (i.e. encounters wear) has an ROI of about 1/5 to 1/2 of its warranted lifetime. If it's installed in a region where the price difference between exported energy and imported energy is big enough to warrant a battery in the first place. In a net-metering (import price == export price) region, consumer-installation batteries are useless no matter what. (Unless they're island-mode capable and used solely for blackout mitigation.)

[@brentverhaegen1880]

When sizing these (AC-coupled) battery systems, do you assume a 100% efficiency of charged vs discharged energy? Because that's not really the case. These are the efficiency numbers for an average AC coupled battery system: - AC-DC conversion to charge battery - 90% efficiency - charging battery - 98% efficiency (in case of LiFePO4) - discharging battery - 98% efficiency (in case of LiFePO4) - DC-AC conversion - 90% efficiency Overall efficiency: 77.8% -> Let's round up and assume 80%. Would this change the advice you give to your customers and how you size a battery system (knowing that they only get 80% of the power back when the sun is gone)?

[@Arachnoid_of_the_underverse]

Given the energy being generated by such solar panels Im surprised one of their offerings isn't a battery bank that acts as a reseviour for the charger, so it fills up during the day and transfers it to the vehicle when connected at might.

[@leetipping-ns3yn]

How much does 60 khw cost in this situation? It's 10k if you go fogstar

[@paulnextlevelbusiness2257]

So much easier if you just calculate a days electricity use excluding EV charging off peak.

[@thereefaholic]

Size the batteries to carry the load of your home through the night and hours of darkness. Then size the solar panels to charge it up in a single solar cycle

[@AaronRumboldUK]

I'm extremely curious to know that second property was perhaps over-specced with solar - and would this be a case where installing a wind turbine might have been something to consider - especially factoring in their solid baseline consumption 24/7 - would this example have reduced the need for such a large battery, and led to a more even distribution than the final choice. Obviously wind is an entirely different beast, when it comes to size, planning consent, maintenance, and the life expectancy of a turbine when compared to solar

[@tony78652]

Jordan will a Eddi give the info a Zappi does?

[@scudest438]

Can we have a follow up on consumption on both houses in 12months time following the batter upgrades?

[@yellownev]

I’d be I interested in if you had any issues with the DNO approving the G99 application based on that storage …. Do the DNO’s ever limit the production and storage ? Love you to do a vid on G98 and G99 application/ approval process.

[@Umski]

DNO doesn’t care about battery capacity, only the max output that the inverter can potentially discharge to the grid - 3.68kWp will go through as G98 anything more will need G99

[@yellownev]

@@Umski now I’m going to have to find the vid where they did restrict part of the install, can’t recall if it was the feed back in - I guess it must have been.

[@yellownev]

@@Umski found it …. It was Scottish power limiting an install to max 4 Kw back to the grid via a G 99 application/response. Have a search for what is a G99 application. Interesting video I think Artisan should show their inspections makes interesting content

[@Umski]

@@yellownev indeed I have been through the very process as I have an existing G98 compliant PV inverter which is limited to 3.68kWp export (even though on paper it can generate 4kWp), but I added a 3kWp AC coupled battery inverter recently - in principle my overall system could export a total of 7.68kWp (although the battery system is set to self-consumption but in a fault condition this could happen) and hence the application to UKPN was done as a G99 - no drama, it was all done via their portal...DNOs are obliged to allow 3.68kWp max AFAIK, anything bigger is then dependent on local grid capacity and/or subject to expensive upgrades hence the slightly more complex application process...

[@yellownev]

@@Umski thanks for the info and shared experience. Can I ask are you a DIY’er and completed the g98 and g99 forms or are you a trained installer ? I stopped at the application stage as I was not a trained installer and thought they would not allow my install due to this?

[@jennyli7749]

I’ve got a 12 panel solr system + 9.5kwh battery…is it sensible to add a battery to capture excess solar?

[@UndercoverFerret404]

How much production do you lose on the 12 kWp system, due to it being enclosed on all sides? (no ventilation)

[@humphshumphs]

On the second customer, are you going to be removing the original battery, or leave that in, giving even more storage??

[@hans.vbaalen]

2nd house is, 60kwh (on top, so 80 total?) seems like it's a bit over the top, unless energy independence is the key goal. In the winter I doubt the sun charge the entire battery and in the summer there is very limited heating requirement at night. Better make sure the heatpump is programmed to heat the water cylinder during the day (my instal came with heating at night, which is doubly stupid as not only does the sun not shine, it's also less efficient as the temperature is lower. Definately a case of law of deminishing returns, wouldnt have more than 40kWh installed there myself

[@marymadigan9707]

Nice video very well explained nice one 😎🇮🇪👏

[@popalop5680]

On a 3 phase installation do you need 3 separate batteries?

[@adampetherick]

Depends on the PV inverter, ours is hybrid and the batteries are connected via DC to the 3 phase inverter

[@philij83]

I have solar being fitted this week and researching tariffs it appears I can keep my Octopus intelligent giving me 5 hours overnight at 10ppkwh and use SSE export to be paid 12ppkwh for solar I produce. Why would I need batteries? I cant think of a good reason at the moment. Genuinely interested, but I cant see it making sense, well especially in spring/summer/autumn...?

[@Regnedi]

Great video

[@coniow]

When we installed our first array in 2011I aimed at having enough solar generation to cover our needs even on dullish days, with plenty to spare on sunny days. This was before domestic battery storage was a 'thing.' In 2018 we added a second array on the front of the house, with a Tesla Powerwall 2. In the first 2 years after fitting the battery, we were importing nothing for about 7 months of the year. We signed up to the Tesla Tariff with Octopus (now ended, replaced with the Octopus "Flux" tariff), and things got. . . . . . confusing. (Charging on the cheap rate, exporting at 16:00 hrs peak rate.). With the Flux tariff I now have my battery back under MY control, back to no importing. I CAN chose to export at 16:00 hrs (as I have just done now), but if the following day is going to be dull, I will save the energy to cover that day instead. As there IS now the option to sell your stored energy at peak rate, is there an argument to increase storage capacity to utilise that feature? It also gives the ability to cover house use for longer when there is more than one dull day. I don't have the energy to try to make a 'commercial' case for it.

[@azlansharom7011]

Jordan, how did you factor for the batteries being fully charged/discharged daily and what effect that has on longevity? Thanks.

[@James-zu1ij]

I think a Sunamp heat battery would be a nice addition to soak up some of that excess energy. They last many cycles

[@northeastcorals]

New modern batts are said to last around 10 to 15 years if all goes well but I'd guess this will vary massively between batts & how they are used etc. Obviously this is a big component of working out your payback which nobody seems to mention (especially PV salesmen).

[@OraEtLabora0]

14:24 how long warranty do MyEnergi offer on those inverters? and packs? or it just one for all their battery-hardware?

[@OraEtLabora0]

and would the client share estimated ROI, based on their current consumption patterns and current energy-price (whatever tariff they get put on)? (including Artisan install cost - i'm not interested in the actual quotes, only in ROI) THANKS!

[@mark_just_mark]

Why are you installing single phase solutions on a three phase property?

[@mikebarry229]

Hes installing 20kWh of batteries on each phase making 60kWh in total, unless you are referring to the original 20kWh installation which might have been on one phase I guess, I dont think he said.

[@mark_just_mark]

@@mikebarry229 Surely this means that all three phases need to be balanced which isn’t generally the case… How does it work if power is stored on phase 1 but utilised from phase 3?

[@adampetherick]

We have the exact same setup as the original solis + pure drive they have and it is a 3phase inverter

[@artisanelectrics]

The original install of 23kWh was with a three phase inverter - the new additional install of 60kWh will be 3 x 20kWh systems one on each phase. This way we have storage which can cope with both balanced and unbalanced loads.

[@mark_just_mark]

@@artisanelectrics Surely the best way to do that is Three Phase across the board and let the inverter manage any unbalanced loads?

[@UnitedSpotlight]

What about octopus flux tariffs now that use the grid as a battery basically and rasied export rates now compared to a few years ago. I'm starting to think the further down the PV and green rabbit hole we all get the less need there will be for battery's as export rates will be good enough to cover the buying some energy back in winter etc. I think the way we're going batteries are useful than the were 2 or 3 years ago when export was like 4p now you can get 15 to 20p export the cost of battery's upfront is less attractive

[@buttonmonkey6845]

I was thinking the flux tariff would mean a smaller battery to get you over the hump of the peak rate and most of the rest of you import costs covered by what you export from your PV.

[@AAW-Electrics]

In your first example, with a 20KWh battery you would level out all of their typical usage but only half their car charging cost (still a great result) but if they doubled their battery storage to 40KWh, would this mean that they could charge their car for "free" and not have to import any electricity from the grid at all? Or am I getting this wrong? I understand that normally this would mean that they have 50% of the battery stored energy not being used up, so effectively wasted, but would this really be a problem? Thanks. p.s. amazing videos, thank you.

[@klapiroska4714]

Double the capacity, double the cost of the system. If you buy your electricity at a market rate, the electricity is - in general - cheaper during the night. In general it doesn't make financial sence to have battery capacity to cover occational usage during night time, as the system cost is probably much higher than what you'd save by not importing that energy from the grid. Even now you need relatively sunny weather and high electricity costs for a solar+storage to make financial sence. But these conditions do exist at least in some places. If you'd like to get more bang for your buck, you could try to setup other systems in your home to act as batteries. This would include heating your house a bit more during the day and let it cool down a bit during the night (like 2 or 3 C deviation from the normal temperature), and heating up the water heater during the day and not right after you've shovered. That way you'd use your house and water heater as a kind of battery, and you might get similar reduction in imported energy but with a significantly smaller and cheaper battery.

[@nickbea3443]

You call that first one a "smaller" system! Their consumption is multiple times higher than the std household.

[@InTruServ]

Is that the 20kwh system? Just checked our domestic consumption for 2 adults and 2 small children, had central heating, no EV charging, and we are anywhere between 12 - 16 on an average day, peaking @ 22 on one day this month so far. What’s everyone else’s consumption like? We do have 1 established member of the family who thinks switches only work in 1 direction though 😂🤣🤦🏻‍♂️🤯

[@Rockrees]

​@@InTruServ 2 adults and 2 children household here. We're a high usage household at an average of 15kwh a day, but we have a hot tub and a frequently used gaming rig/heater. We have a 6kwh solar/battery system and on sunny days, are completely off grid 😊

[@InTruServ]

@@Rockrees similar then, but we don’t have a hot tub or gaming rig. Just double checked March as a full month, /31 days 421kwh total, so average of 13.6kwh per day. Interesting, have our solar & battery storage training next week so will be more into system specifying/design at that point. Lots of interesting options coming on the market and solar tiles making things look even neater, plus no pigeon roosting risks

[@bluegremlin0]

​@@InTruServ Two adults and one ten year old child, 9kWh/day average. Electric ovens, gas hob, heat pump tumble dryer, gas central heating, work from home.

[@iansyme3535]

What about the cost of these batteries and associated electronic wizardry in the second property? Also, I assume that they are one of the rare instances where there is a 3 phase feed to the property which is why you have 3x5kw inverters. In a single phase setup would it be possible to fit a 10kw inverter and say a 20kwh overall battery system? Too many unanswered questions! You also did not touch on the very low export to grid rates you get nowadays compared to 10-15yrs ago when it was quite lucrative to do so which is the main reason I assume that one wishes to capture all the energy you have generated ......

[@stuover73]

OK video but depending on the electric provider can be pointless. i.e. Octopus Flex change at night and sell during day

[@marknorman3582]

We are not installing batteries with ashp when installed. Its a difficult call. Solar hot water with the ashp and 300-500 thermal store maybe better. Or air to air heat puumps Good luck all.

[@tommytinkler1708]

Clearly if you was generating 2-3 times the required amount required then the export rate you would get around 12-15p per unit would cover the cost you was using later. What would the point of a battery system be then?

[@wajopek2679]

I'm shocked that today, a residential property consumes so much electricity. Is that just the heat pump and EV? What is outlay and the ROI? Give me a diesel and mains gas

[@15bit62]

They must be powering the farm as well as the house surely.

[@kevxsi16v]

@@15bit62 a farm will use a shit load more than that .I’m currently burning through about 60kwh a day easily but also in the process of installing a victron setup with 55kwh if storage.

[@15bit62]

@@kevxsi16v I was assuming *some* of the farm, not all. 60kWh just seems like a big number. Even at -15C here in norway my place takes less than 50kWh in a day, and we don't have gas (no-one does here). We don't have a heat pump either. I guess i've forgotten how bad UK insulation is.

[@kevxsi16v]

@@15bit62 I heat my home with a log burner my biggest user is fridges and freezers for produce and pumping water for irrigation and domestic use for several properties. Also grow lights for plants as well.

[@djtaylorutube]

Now compare again on what that 1 gallon of diesel does for you given that it's about 40kWh of energy (not including the energy to extract and refine it). You'll get what? 50mpg from a typical 2.0l engine thereabouts. The EV will travel about 150 miles for the same 40kWh and another 75 if we factor in the energy that was used for extraction and refining of diesel. The question is efficiency.

[@peto22]

So, how long will it take for a battery system to reach 100% ROI at the current price level?

[@dalroth10]

In the second site case I think you will be needing between 60kw and 75kW of battery storage

[@johnh9449]

What happens when you have no history to go from? I did the same exercise for my 8kWp system with heat pump but arrived at the answer of 15 to 20kWh just by plotting the monthly kWh figures for PV excess over ASHP load and ASHP consumption (less the excess PV) consumed over the rest of the day. The curves cross over in April and October either side of which either the battery size is limited by lack of solar or lack of load - the optimum battery size is where the curves cross - the peak point of the lower of the two curves. I opted for 15kWh because another 5kWh would have created another battery stack with BMS and was not as cost effective.

[@peteroffpist1621]

All cases are different just like driving patterns on a car. At the moment we get well paid for the electricity that we produce so keeping it all for our selves is not the best choice. We consider when we can’t on average produce electricity our selves like at night and size the batteries after the night consumption. So 10 kW battery is plenty. During the day and we are producing we always charge our cars. If the price for electricity is low like often at might we charge our cars and so on. Batteries are expensive so ROI is very long on a large battery pack.

[@tomrivans9102]

Why aren’t they on off peak tarrif?

[@Fritsvrolijk]

Gif us the price off all this Fun Sun products Thanks for the video Pro

[@henrystevens2258]

Bird skirting on which is a expensive con

[@macky4888]

MODBUS is the communication protocol connecting the meters to the inverters to chargers etc. it is not the components itself. Get your terms correct, it makes you look more professional, and not a rookie.

[@stephensails]

12Kwh peak??

[@G6EJD]

You didn’t once consider efficiency of battery charging (80%) or discharging (80%) and the round trip efficiencies, so your basically guessing what size battery is required rather than at least trying to get a more deterministic answer.

[@1over137]

The twist with solar is it will split the wealthy and the poor, again. The people who can afford solar pay much less for electricity, so they pay less to the DNO to support upgrades and repairs. Some of those upgrades and repairs are needed because of the increase in local generation and export. The only way the DNOs and retailers can continue to make money and fund those upgrades is by reselling the export energy at a higher price to those who don't have solar, because they can't afford solar. Also, the UK fuel mix is such that the grid power is some of the cleanest in the world breaking even with kWh emissions efficiency of natural gas as a heat source. (Normally closer to 3:1). By bringing online more and more storage over export we may actually shift that fuel mix towards the negative end, by reducing the total roof top solar export. Additionally we don't want to run into grid saturation overnight. If a large enough portion of overnight demand goes away, there comes a point where it's hard to sustain a stable grid. It becomes less profitable to run plants over night. So more gas plants will go "start/stop" cyclic which lowers their life expectancy and destroys their efficiency. They much prefer to run 24/7 365. The think tanks are suggesting we fix this by going all in on it. Go for a totally distributed network of local micro-gen, local micro-storage and using house batteries and EV batteries as capacitors to move charge around the grid. The idea is removing the base load entirely by generating it in a distributed form closer to the loads. The more controversial aspect of that is who pays for the storage wear and tear and to do properly, those heavy loads in your home will need to be centrally controller and whether you can or more likely "when" you can use them will be determined by your local area grid generation and storage status.