Just to mention the car option usually needs1.2-1.4 kw of power to kick in so it will waste anything below 1.4kw. Manual if you have a inverter with some smarts can be managed with stuff like home assistant. I divert almost nothing and home assistant switches between car/battery/not manual. A raspi (and bits n bobs) is about £100 to make the manual automatic very cost effective
Agree, totally depends on your use case and where you live. With net metering in my area, I divert excess summer production to the grid and pull out the balance of that surplus over the winter at the same rate (cost). I haven't had a power bill for 5 years.
@@tonygoodin5099 That is the rule in California, but it is changing for new solar not accepted by April 2023. Fortunately my installation was accepted last year and it is grandfathered for 20 years. A bit less than 19 to go. I have no battery but until 2030 the federal government will give a tax credit of 30% of the cost. I'll have to think about it...
We have a diverter to the hot water tank, when it can't take any more ( and during the colder months ) we manually switch on a little 750 w fan heater, or alternatively the slow cooker, it's a low steady draw and come 5/6 pm your dinner is already cooked and ready to eat. 😋
Exactly right. I produce about 32 KWH per day from my panels. Our cars are programed to charge only during the hours the panels are producing. And we only plug in the cars when the sun is shining. We also limit washing clothes to sunny days. As a result. We sell very little energy to the grid.
@@davidlewis4399 Yes. They originally put out up to 52KWH a day. But now most days it is about 32 KWH. But, not today. The sky is overcast. But the cars are already charged to 80%.
For us 1.house consumption 2. House battery 3.cars 4. Water heat. House batteries transform the value of solar, and deliver a winter dividend as we only use solar or off peak.
We have a 9.5kw battery and it is a great way to store energy for when it gets dark. We had washing appliances on which dipped into the battery in the morning but solar topped it back up by lunchtime.
I have similar. At this time of the year I also charge the battery when there is cheap electricity available at night (I'm on Octopus Agile so it's not always available). The price often drops to zero and sometimes into negative costs (they pay me to charge the battery).
@@Kosh42EFG I was pretty lucky. I originally had a 5kWh battery but its capacity dropped like a stone. The manufacturer didn't have a replacement available so the gave me a larger 8.2 kWh battery as a replacement. I also have a water tank which I can heat if the price drops. Just can't justify the cost of ASHP quite yet.
I have a DIY solar install so no export tarrif. Previously I was exporting surplus for free and so was getting obsessed on juggling house loads to use up surplus. No heat pump, HW cylinder or EV. Getting the house batteries were so liberating. Just turn on stuff whenever I want. Though when summer comes, and there is the possability of reaching 100% charge, I might be back into the old vicious cycle!
@@glenhouse46 I went for the pytes LiFePo4 server rack batts. 10kWh worth. The charge system is all analogue, which is less than ideal. So have some careful juggling of charge voltages and loads to do when summer comes.
We had Solar panels Solis inverter and 2 pylontech batteries (7kwh) installed last week,we also have Zappi for Ev. Can’t work out how to charge batteries overnight on cheap tariff and installer doesn’t seem to know. Also can’t seem to program EV to come on overnight(I’ve set Eco+ boost schedule) I just have to wait until as late as possible so minimal charge before the 2am cheap rate kicks in! ☹️
I only had the option of diverting to HW but I recently got a 4.8kWh battery - HW diversion had saved using gas for 250 days of the year (8kWh per day otherwise), but with the battery my preference is to use the electricity for electrical appliances as the water can be heated by gas if needed (which is now worse!) - it took me a while to stop the two fighting with each other (DIY implementation!) - this is where the MyEnergi system is more flexible as you can change the priorities on the fly. On a good sunny day now the battery will get to full charge by midday and the rest goes into the HW and this will only get better as the days get longer. In the summer I will still have excess but until I get an EV or bigger battery that won't be much anyway - I think we were only exporting 600kWh out of 4200+kWh generated per year anyway so there wasn't a huge proportion going spare before the battery - which is the dilemma of then getting an EV and/or HP in the future and trying to move away from gas - not enough PV!
Battery also has the option of being charged overnight on cheap electricity, when little sun is forecast for the next day. Batteries are great, except when they are full. We also seem to loose as much as 10% due to battery and inverter efficiency, so if it's possible to use power when it's generated, I think that's the best option. Car is problematic for us - although it's sometimes on the drive when we have excess solar, it doesn't seem to like stop-start charging or even just being charged at a low rate. Once the internal electronics shut off, our 22kwh Zoe goes to sleep and it stops charging and can't be woken up again. The main manual option for us is an oil-filled electric radiator with 2 power levels - this at least enables us to save some gas on the central heating system. Other manual options include washing machine, or tumble dryer (on the low heat setting).
Practical videos of commonsense value. Must move away from slogans and flag waving. With the current possibility of power cuts, gaining security of supply should be an important factor even at cost. Diversity important. Keep at it!
Great video EVM. I've had solar panels for several years and got a EV around 18 months ago with a Hypervolt charger which can utilise some of the excess solar but I still export 2000 kWh to the grid so a battery is the next step. Currently looking at a 9.5 kWh Giv Energy set up similar to what you have utilising the interest free loan we have access to here in Scotland 👍
Like I said we heat our water with excess solar but it isn't wasted like you said if we aren't home. Our tank is well insulated & heating the water saves us oil which ain't cheap!
If you are a bit of a geek, you can use Home Assistant to automate using excess solar. I'm currently making an emersion divert myself for £40, the cost from companies is excessive.
A home battery is expensive but also allows you to charge it on the cheap night rate so delivers during the winter as well. A good option for EV owners is / would be vehicle to load so you can use some of your very big car battery to power the house when needed. Of course it depends where your car is and what range you need. Earthing issues seem hard to resolve in the UK though. I have had panels for 18 months and in that time I have exported 2,900kWh (£1k worth) to the grid for free whilst importing 5,800kWh - virtually all on the GO night rate. I do have a 8.2kWh home battery but have been lazy in setting how much to charge it up on the cheap rate at night during the summer. The GO rate has gone up from 5p to 7.5p so I will take more care this summer.
My Go contract is up for renewal on 10th Feb and Octopus are saying the cheap rate will be 12p per kw and around 40p at other times. The standing charge has almost doubled to 48p per day!!! Intelligent Octopus is the cheapest at 10p/40p. On the plus side Octopus say they don’t charge for disconnecting your gas supply if you have an ashp installed by them or anyone else 🙂 This will save you around £90 a year on the standing charge.
@@davesanderson1843 When I tried Intelligent Octopus the rates were much higher than the example ones they used in the advertising so I switched back. The standing charge increases are unjustified and need to be looked at by the authorities
@@gap9992 the standing charge increase are due in part to the number of suppliers who went bust when the wholesale prices went up, also increased network costs and it subsidises warm home subsidies. We know makes up the costs, better oversight of firms before the wholesale prices rocketed would certainly have helped, Bulb being a prime example.
I use an Eddi to heat water, big advantage is it can use small amounts of surplus energy. My car Zappi charger needs 1.3kw to charge car. So I set the car charging to priority followed by water, means early morning when not enough surplus to charge car, surplus goes to heat water.
If you can afford it, get as much as possible installed at the same time as the solar panels & save 20% on VAT on everything (components & labour). The solar panels & installation labour are VAT free at present (in England at least). However, get any of the other stuff installed separately at a later date & you will be charged 20%Vat so it pays to get as much as you can afford done at the same time as the solar. I've got a 10 panel Perlight array, 3.6Kw Hybrid GivEnergy system, 9.5kW GivEnergy battery, Zappi home charger, Eddi Immersion diverter & a new consumer unit all being installed at the same time in March / April. 0% Vat on all of it. I also had a replacement Stainless Steel hot water tank & longer reach Immersion heater installed recently (old one was 38 years old) so I can store more hot water. However, I did have to pay 20% Vat on the new HW tank because it was installed separately by a different company to the Solar. I don't have on EV yet. I will probably get a used hatchback EV later this year for my wife to use locally but I'm keeping my petrol estate car for the foreseeable future.
Indeed, that is why we jumped when the electricity cap started rising so fast. Also - get as many panels as possible. Our main roof took 10 (4kW) but for just an extra 5% on the bill they put another 5 (2kW) on a lower garage roof. In practice it means we get decent generation even in winter.
Interesting and true for almost all scenarios. I have 8.96 solar an EDDI and a ZAPPI and a Powerwall 2. My panels produced 6.2 MWh last year and I exported 3.2MWh. As I am of TEP tariiff my exports net off with my imports. The rate 24/7 is 26p per KWh. So the only figure that interests me is the net imported at 5.1 MWh. I could only move to an off peak rate if I could buy another 1 or 2 PWs. Unfortunately it is difficult to forecast how tariffs will move as all the cheaper tariffs increase in price and not necessarily at the same or proportionate rates.
Great video. But the manual option is so much hassle. Things like dishwasher, washing machine and tumble dryer do not use a constant amount of energy during it's cycle and excess PV energy is unlikely to be constant either. Therefore, it's really hard to predict how much of the excess energy you'll actually use. There's a good chance that you might end up using all the excess plus pulling from the grid (which will be at peak time). And the peak pull from the grid is very likely to cost more than had you schedule the device at night for off peak. So the net effect is that you've wasted that excess PV energy and it's cost you more. Really the only hassle free option is to have a home storage battery. Even a small 3kWh battery would be enough to buffer the excess enough to avoid the problem I just described. You can turn on the appliance when the battery is full and it will guarantee run completely on that buffered excess PV energy.
There are smart sockets (combined with a small device that plugs into a smart meter) that will limit the power drawn to whatever the excess solar is. Would be useful for example for charging electric bike, scooter, phones, turning on pumps to water garden etc. Maybe not for washing machine as that's a more heavy, longer and changing load as you say.
I isolated my heater element in my dishwasher and power that from panel voltage. Off grid and only have a car battery for my house. Hot water is provided by the shown diversion control. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-iaLbLYhPLtw.html I even have enough excess energy for the clothes washer to have its own tank. All cycles use hot water. Most solar people waste so much energy.
I have a battery and immersion diverter. Interestingly I was watching another video that was saying, on cost alone, you are better selling the power and burning gas for hot water. I do not have an electric car meaning Octopus are paying £0.15 per kWh exported with their fixed rate and there is the Agile rate as well that tends to be 20-25p during peak period. Great if you have some spare capacity in the battery from when the sun was up.
It is all about cost per unit of energy. The author of the video was being paid something around 5p from his utility and paying 35p to get electricity from them. You're getting paid much more for export than he is. How much heat energy do you get from 15p of gas? Subtract from the any furnace inefficiency and any cost to maintain your furnace. The cost to maintain electric baseboard heaters is pretty much nil and they are 100% efficient--no more and no less.
I was thinking about this the other day. What about using it for heating if you've got electric heaters. If you're not home during the day then you could have the heating on all day and come home to a warmish house In the winter it's likely to be lower and you'd need a heater that could run on low power
Be careful if you have an immersion heater and a battery - if the immersion divert comes on at too low an export value, you can end up with the battery pushing a few W into the grid, the immersion divert coming on, and then draining your battery! You can change the trigger level to make sure this doesn't happen. And then if your battery gets full and your solar isn't above that threshold, you can press the boost button and pull from the solar and the battery for 15 minutes. When the 15 minutes is over, your panels can drip feed back into the battery, and you have a few kWh extra heat in your hot water tank. :)
I turn on my IR panels remotely to use the house structure as a heat battery. I just look at my tesla app to see if the panels are producing. I need to get a Sunamp battery for hot water.
The Zappi can only charge if you have over 1.4kW spare, otherwise you need to "top up" to 1.4kW with grid input. And for a real rabbit hole, I use Home Assistant to do lots of my excess solar diverts.
For me the solar battery always gets priority, then it's usually the hot water EDDI, then the Zappi, but if the car's below 50% or so I usually tweak it to give the Zappi more priority
We have the Tesla Powerwall 2 with a 13.5 kWh Battery, the MyEnergi Eddi and Zappi. Like you say, the battery is my number one choice,then hot water, then EV. Last year with use of a night time tariff, my battery enabled me to purchase 89% of my power at the cheaper night rates and only pay higher daytime rates for the remaining 11%. We did find that our East facing roof solar of 3.7kWh was mostly used by us, so when adding the battery I also added the same solar amount to my West facing roof. This meant we could easily fill the battery for 7 to 8 months a year from solar, but I rarely charged the EV as I charged at night. We exported less than 400kWh to the grid. Now with an ASHP, this has altered our usage patternmassively in the winter months.
@@markbrown9803 To be honest, no it doesn't as the Powerwall and solar could not power us in the winter months before the ASHP was fitted. However due to the amount of energy you don't use due to solar panels filling the battery, it really helps to offset and reduce the monthly payment. And that is what it is all about for me! In the winter we use almost 30kWh to run the house each day and the power use would be from Cheap overnight tariff, filling battery and then in the day, solar plus battery and it would run out somewhere arounf 9 -10 pm when we reverted to paying daytime prices. Now the ASHP uses 20-30 kWh in general, up to 40-50 kWh when temps are below zero. This is in our 5 bed detatched house with little to no wall insulation. Also our E/W facing solar is only giving a max of 6kWh on a sunny day. I am in process of adding extra Solar PV, to a South facing gable end that will be angled with a priority for winter, to help assist the ASHP energy use. We are also awaiting a company to remove my old degraded cavity insulation and replace and fill the void with a much better option. Hoping this will reduce my use by around 30%. For info, my E/W 7.56kWh solar gives about 6200kWh per year and ASHP has been providing 18C with a drop to 16C overnight for about 3600kWh. Hope that helps.
It’s really interesting to see those figures, thanks! I’m just at the start of research of panels+battery then eventually ashp. It would be great to run off grid as much as possible but my house also isn’t remotely modern!
@@markbrown9803 I am dragging our 1973 detatched house to be more modern and have managed to geta smart meter where they told me I couldn't due to lack of mobile signals and finally in the next days my lack of cavity wall insulation will be sorted by removing the failed stuff and filling it up with the modern!
The immersion hot water setup works great for our house, every two days have it on for an hour for showers later. I'm not sure everyone realises that most tanks have the immersion switch next to them. With ours we originally just let the gas heat up the tank. Be nice to have it automatically turn on when battery is full and have excess power from solar, but for now fine with turning it on when needed.
Check out a Sonoff TH16. That's a 16amp WiFi inline switch. Also can have a temperature probe that plugs into it. Costs about a tenner. At its simplest, it means you can manually switch that immersion on from your phone, but it also gives you smarter options. I have mine set come on at night when our elec is cheaper than gas to use our immersion to heat up our tank. But there's no reason it couldn't be connected to whatever system is telling you that theres excess solar. If you're feeling technical look up tasmota. Custom firmware you can flash to it to improve integration and options.
@@davidsmonkeyroost Thanks that looks like a pretty useful device that could use for lots of stuff. Will make a note of that and look into getting one soon. Thanks
@@adrianfox7972 no worries. For a smaller truly inline switch (input on one end, output the other) but only rated to 10amp, check out the Sonoff Basic WiFi. It goes for less money. Maybe a fiver if you can wait for it to ship from China for a couple of weeks. I use them on desk light flexes as cheap smart lights and also on my dehumidifier so it runs when we tell Alexa to dry the laundry, and then runs automatically when electricity is cheapest. I also have one powering a 20amp contactor which provides power to our electric underfloor mats.
I bought solar panels and a battery around 6 weeks ago. I have 8 panels and its a 3.28kw system size, I have a 3.68 kw Inverter and a 5.8kwh battery. I have crunched the numbers on what its generated so far and its 126.4kwh. I have self used 77 kWh myself so far and 49.4kwh has been exported to the grid. This seems quite high as a percentage to me. I don't know if this can be altered and I can reduce how much is exported to the grid due to the smart export guarantee because I'd prefer it to go into my battery and be able to use it at home
Hi Adrian, we bough solar panels 3 months ago - 6kW panels and a 6kWh battery. So far we've used 393kWh and exported 83. We do have a PHV car so that takes up to 6kWh to charge, most days but not all. So percentage wise we're using a bit more than you and exporting less which is probably down to charging the car and manual timing of washing machine and dishwasher.
We have 3kW of solar, which we’ve had since 2011. Before we got a battery we were exporting about half of the generated energy, (i. e. our self consumption was about 50%). We have had a GivEnergy 5.2 kWh battery since last May and over the whole time since then our self consumption is about 80%. In January there was so little solar that the battery was never full, so pretty much everything that was generated went into the house, the car or the battery. Our self consumption for January was 95%. So your 61% self consumption does seem quite low. We have an electric car, a Zappi car charger and an Eddi solar water diverter, so there’s pretty much always somewhere for the solar energy to go.
@@RogerBamforth yeah I thought so. I’m all very new to this and I would like to make sure were consuming the majority of what we generate. From my app it looks like my battery is being filled from the grid and my solar is being used or exported at a 60/40 split
@@uTPH1 You’re using a good 82% of what you’re generating. I’m wondering if because these are the darker months that I’m not generating a lot and I’m obligated to provide X amount of kWh to the grid?
@@adrianbick1299 We are currently using just solar to fill the battery. We are in the process of switching to Octopus Go and will then use the cheap rate grid energy to charge the car and top up the battery when there isn’t enough solar.
I'm getting a small (East facing) solar array next week - six panels with a 3.6kw inverter, I think. I already have an EV (BMW i3) and a Podpoint charger and use OctopusGo. I was hoping that if I bought a Zappi and swapped it for my old charger I could divert any excess solar into my car, but reading the comments below it appears you need an excess over 1.4kw to avoid any grid top up. I doubt I'll even get 1.4Kw on a good summer day so not sure a Zappi would make any sense. I think I'll monitor the panels of a few months and establish what they actually produce before thinking about a battery. I know that being on OctopusGo I can only get the SEG export tariff, of around 5p.
Your advice might be a tiny bit out of date. It's now more cost effective for me to export any energy than divert it, using Octopus Flux, and also having a sufficient amount of battery capacity. I don't however have an EV. I could however get behind diverting it to a heat pump however given that the import rates are around 19.6p/kWh and the export rates are around 21.7p/kWh I make a tiny amount by exporting, typically though for a heat pump a couple of pennies probably isn't worth thinking about. For things that have a COP of 1 or lower, and without having an EV, solar diversion for me isn't worth it.
I agree with your thoughts. I was hoping for some insight as to how the diverters work. Using your example of 300W spare energy and feeding that into a typical 3kW immersion would draw 2.7kW from the grid unless the diverter is limiting the power, maybe by varying the voltage using pulse modulation? (volts x amps = watts and amps = volts / ohms). Resistance is constant so volts has to be varied. I've build my own diverter to control my immersion fitted with a 1kW element. I monitor the PV and house consumption to identify unused energy and switch on the immersion if unused energy > 1kW - it's just a. zigbee controlled on/off switch. Trouble is, the typical UK cloud cover is constantly blocking & unblocking the sun so the PV energy is constantly fluctuating. So any system has to react within seconds. Probably will work better in the summer with less cloud cover and stronger sun.
The current clamp has the added benefit of being a feedback loop, so if the immersion pulls slightly too much, the current clamp tells it that you have started pulling from the grid and it can modulate the power to the immersion.
Try Octopus Cosy. The export rate is 15p per unit (kWh). But, there's always a but, you need a battery to meet your consumption demand between 17:00 and 20:00 otherwise Octopus charge a penalty rate >50p per unit.
Hi EVM, greetings from Oxford. Our roof is not optimal for solar PV, we have an EV and Octopus Go tariff. We use off peak electricity to heat our water tank and charge the EV. We’re thinking of getting a home battery to charge with off peak electricity, then run the house during peak times. Would be interesting to see your take on this idea.
What battery are you using now? Are you still using the Give Energy battery and are you still happy with how it works, would you use something different now if you could take your experience and start again?
Rather than an immersion heater divert option, there should be a heat pump divert option. Ie the heat pump controller goes "ooh 300w of electricity is being exported" I'll ramp up my hot water option by the same amount.
You can set this up, for example with the Eddie solar diverter using the optional relay. And as you suggest and EVM says, the heat pump is probably 2-3 times more efficient than using the immersion. But there can be an issue with this. My heat pump (and guessing most heat pumps) won't work with small amounts of excess solar. Mine needs about 1,500W and is often using more than that for the hot water. Second problem is consistency of having the excess power. If you have intermittent solar, as clouds pass over, the heat pump is going to be very inefficient as it will turning off and on all the time. But the immersion will work on just100W of excess power, and on changing and varying amount of power (mine is up to 2,700W I think). Finally my pump will only heat up to 55C (although I know other models go higher) and the last 10C have a much lower COP, where as you can get towards 65C of stored hot water energy via the immersion. So on a lovely sunny day with lots of continous excess solar, heat pump is the 'best' option, where as through winter the immersion works much better (for me).
@@jamesnorthway9999 I believe this is the so called SG-Ready feature. EVM, please do an analysis on SG Ready. It's not obvious, to me at least, at which point SG Ready benefits would outweigh the drawbacks.
Had a 4kw array fitted 12 years ago. We get £0.6025 per kw generated & use excess to heat our water via an Immersun unit. Would consider a battery but at £10k & a waiting list not viable for us at our age.
Unfortunately, this is AC divert only… I’d like to understand what’s possible with oversized PV plants, where there is (at some points) a production that exceeds the inverter power ?? Oversizing makes perfectly sense, in order to maximize production, but is there any way to ‘capture’ what’s in excess of the inverter’s capabilities ?
One thing to point out is the car won't start charging unless 1.4KW is available, as per the charging protocol. So using 300w will mean taking the rest from the grid or in my case the house battery
I use a Zappi charger, which does its own balancing and diversion thing, but my car, Kia eNiro, needs a minimum of 1.1 kW to charge. We have a Solar IBoost to do the hot water. Just waiting for myenergi to pull their finger out with their rebranded Chinese battery and take the next step. Any tips? Great bit of well thought out information, thanks.
I was looking at the Libbi as a GivEnergy alternative since GivEnergy have firmware issues causing State Of Charge to wander. Can you explain your experience with Libbi and why you think it’s average?
The firmware issue will be solved within the next month or so I believe, and it doesn't affect many. The libbi is a rebadged battery from KStar that has average specs yet are charging about 30% more for. It's way overpriced and does nothing unique. Wait a few months for the new GivEnergy All-In-One battery. Way better spec and cheaper buy about £2k over the libbi.
@@ElectricVehicleMan I don't think I'd be relying on the GivEnergy all-in-one being available any time soon. They've only just started shipping Gen2 inverters and the much fabled car charger has been "coming soon" since May last year.
I’m getting solar/battery in a few weeks. The immersion heater diverter is expensive (c£550) and my Ohme charger doesn’t work with solar. So it’s c£1000 to change for a Zappi or similar. High cost extras!
The minimum surplus required to divert is a factor. As others have said, car divert requires about 1.4kW. An immersion diverter like the Eddi needs a few hundred watts surplus before it will activate, but it can successfully mop up the 300W excess here and quickly ramp that up and down as the solar generation and household usage varies, requiring no grid usage. If minimising imported energy is a goal, it is a good solution. What is the minimum power required to charge a battery like the Givenergy?
My battery charges from about 10-15W upwards, which is 0.2A on a 48v battery (Pylontech). Depends more on what the inverter can modulate down to than the batteries.
I did have a PV to immersion diverter, cost a bit over £200 for the device which failed in less than 2 years. (Can't remember what brand and have no intention of naming names) After that I built my own for under £40 using instructions and firmware on the open energy monitor forum. Whilst the £40 option will almost certainly pay for itself, I regret getting the £200 one even if it hadn't failed.
@@ElectricVehicleMan yep, just a warning everyone needs to double check their tariffs. Lots of solar forums (especially FIT users) assume a diverter will be a benefit. In some scenarios it could be a loss. With ASHP cosy or eco7 could make more sense than Go and both allow outgoing fixed afaik.
@@ElectricVehicleMan I am swapping tariffs between Summer and Winter. I find using Go in winter and Agile Export in Summer is the best compromise. Octopus are OK with this providing you don't try to change more than once per month.
Yes agree with you Ben , I am with octopus outgoing 15p export rate so it earning me more as gas costs 10p so it cheaper to heat my hot water with gas and allow the export. Also I would never recoup the capital cost of fitting an eddie diverter . I will save the money for a battery instalation in due course.
I’m just on the edge of “it’s got to be quite a lot of power to justify a diversion to the immersion”. For me… with a battery on site the difference between exporting and diverting is just 3.4p/kWh… (because the import is going to be overnight, not during the day once I have enough to export) so any “magic box” has to be very cheap.
The immersion just takes what is left over as excess, could be a couple of hundred watts, right up to it's max rating eg 2KW. That's the great thing about them, cheap and easy. The auto switching can be cheap too, no need for an expensive one. Just a version of solid state relays.
This video doesn't take into account Octopus Agile Outgoing. I was going to get a battery when I had my solar installed but using Agile Outgoing means I get much more to export and at some stages last summer I was getting paid to export more than it cost me to buy.
Hello I’m new and currently awaiting installation of EV charger, solar and battery. Am I right in thinking that solar divert would need to be > 1.4kw before going into Zappi? Also I’m a bit worried about the integration meaning I want the solar to go to the battery first rather that EV. Off peak charging will change that and I’m worried that EV discharges battery rather than cheap grid power? Seems like a technical minefield…
Your suspicions are correct. Managing the flow of power between solar, EV, house battery, water heating and appliances can be tricky if you want to optimise your consumption. My EV will only charge at a minimum of 1.4kW (via a Zappi) so on poor solar days this doesn't work. However the house battery and Eddi are happy to use this low rate energy so it isn't wasted until both are "full". I think you need all options - battery, EV, water heating, manual and grid to get the best out of solar.
I find that our Givenergy system will take the power from the battery if I plug the car in when the sun is out and the battery is full, so after a few hours of car charging the home battery is only 2/3 full.
If I was you I'd look at switching to agile outgoing octopus... its a different price every half hour but most of the time its around 10p or more so if you are on 7p over night charge up its a win imo... thats what I'm on
Like you say i have 10kwh battery to charge over night and charge 2 cars at night and a 7kwh sun amp battery and then in the day I use what I need but send to grid to be quids in if I don't use it
Andy, coming back to this after the IO 7.5p/SEG 15p video the other day. Key question now, how to divert ALL Solar to the Grid? Is this the lifeline for the Eddi and can it do it, so that no excess solar goes to the house, car or battery but every last bit to the 15p rate?
@@ElectricVehicleMan is that just a case of using the Alpha Ess App setting to do that then? I guess. Kinda sad Eddi is totally redundant. I can’t see it going the other way, but, you never know. Anything can happen with tariffs but it’s highly improbable that it will become useful again, I guess?
Interesting, but how often do you have to charge an average EV to make one of these octopus ev tariffs worth while? Bearing in mind the normal day time rate is more expensive!
What I want is a smart plug that turns on with excess, this way I can heat my workshop in the winter and cool it in the summer. But nothing seems to be available
There is another.option as my property was built around 1960 and any excess charge from my panels causes the electric meter to go backwards! I don't want a smart meter.
something I haven't worked out yet having solar and battery installed is why when my battery is showing a charge of say 50% the app is showing sometimes I am exporting to the grid. Surely I should only be exporting once the battery is full.
Batteries have a max charging and max discharging current say 100 amps so for a 5kWh battery the BMS will limit charging power to say 2.5kW. Thus if your solar is generating 3.0kWh, 0.5kWh will still be exported. The BMS will also limit charging current if the battery is too warm or too cold.
If a heat pump is 300% efficient it means for every 1Kw of electricity it uses it produces hot water or heating equivalent to 3Kw of electricity in. A battery can only be a maximum of 100% efficient because for every 1 Kw of power you put into a battery you can only get a maximum of 1Kw back
A battery is almost always NOT 100% efficient because of inverter losses converting DC to AC. It depends on the system. Comparing a heat pump to a battery is comparing apples and lemons. BTW, heat pumps are not 300% efficient in cold weather when you need them most.
Heat pumps move heat from one place to another as the name suggests. They use electric energy to do that, the ratio of energy input (as electricity) to energy output (as heat) is expressed as a ratio, or more commonly, as a percentage. Best case you can see 500%, but that will drop as the weather gets colder. The efficiency is also dependent on the flow temperature, which is why you want bigger radiators ideally, as you'll see better efficiency and lower energy use that way. Heat Geek (channel on here) were seeing nearly 300% efficiency with a heat pump at around 0C on their recent video. Modern ones do quite a lot better than ones from five or ten years ago, whereas gas boilers have been at the limits of thermodynamic efficiency for decades now.
I think the iimmersion is best, I use an Eddi it can work at a lot lower wattage then a car charger can and my water tank stores around 7kw of energy, save your batteries for cheap rate charging and discharge during peak. Remember a battery has losses during charging and usage. A modern hot water tank stays hot for days.
@@ElectricVehicleMan fair enough, how many cycles is your water tank guaranteed for 😉 were on the same page, plan A use it, B store it, worse case export it.
How do you prioritise what order this diversion goes in? Would it not be simpler to just not worry about all the other bits of smart kit and just let all the above options present as a home load and the power will be saved off the bill at some point.. Why worry about prioritising?
If you get the same manufacturer for the various options you’ll just control it from an app. Easy. This was more about what to get first, not which to prioritise.
@@ElectricVehicleMan Will a CT be needed for this to work? On generation, battery? Eddi? Zappi? I know your video wasn’t about that aspect. But what’s your thoughts on it?
PShort answer, yes. I have the Zappi, Eddi and Harvi. Using a Harvi (CT wireless clamp) allows the devices to monitor what is going back to the grid. When it see excess it kicks into actions and moves it to what you prioritise.
Shame we have to faff about with all these options. If only they paid a decent price for exported electricity we could simply use the grid as a big battery, exporting and importing as required.
Indeed, it's a scam given that wind producers get paid the gas rate, which is why the UK energy is so screwed up. At least I get 60p per kWh on the original FIT, the sell back never really factors as I have a battery. The £100 or whatever it works out as for export (I still get paid that too) is somewhat insignificant in the grand scheme of things.
Tesla Energy charge the same for import as they do for export, so you can’t lose. The only catch is that you have to use a their Powerwall battery when is the most expensive per kw but might be justified for some people.
A typical UK immersion heater, is 3kW. Attempting to use your excess 300W by switching on the hot water, in your example... is going to result in you drawing 2.7kW from the grid. I have solar, battery and a traditional hot water tank with immersion. In the summer, if the battery has already taken up enough charge, then switching on the immersion heater makes sense and the solar and battery combined, can take the load. With no battery system though, your solar panels are unlikely to be producing enough to power an immersion heater.
Solar hot water diverters like the Myenergi Eddi control the power (or rather the voltage or current) delivered to the immersion heater element, running it less than full power. So in this example, the immersion heater would only use 300W, with no power being taken from the grid. Of course, it would take a while to heat up at 300W 😃